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Full-Text Articles in Life Sciences

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 …


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 …


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 …


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.


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 …


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.


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. …


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 …


Flora Of The National Reactor Testing Station, N. Duane Atwood Jun 1969

Flora Of The National Reactor Testing Station, N. Duane Atwood

Theses and Dissertations

The National Reactor Testing Station (NRTS) is located along the western edge of the upper Snake River Plain in southeastern Idaho. The area covered in this study comprises 894 square miles of rolling to broken land. The plain is broken by three large buttes, all volcanic in nature. The Snake River Plain was formed by the interbedding of volcanic rocks, lake, and alluvial deposits. The alluvial deposits are Quaternary in age as are the basalt flows, and the three buttes are middle Teritary. The vegetation is semi-desert and belongs to the northern desert shrub biome. Annual precipitation at the station …


Social Structure Of Small Mammal Populations At The National Reactor Testing Station, Idaho, R. Lynn Speth Jun 1969

Social Structure Of Small Mammal Populations At The National Reactor Testing Station, Idaho, R. Lynn Speth

Theses and Dissertations

This investigation examined the social structure of four species of small mammals (Perognathus parvus (Peale), Reithrodontomys megalotis (Baird), Peromyscus maniculatus (Wagner), and Dipodomys ordi (Woodhouse) at the National Reactor Testing Station (NRTS) in Idaho. An understanding of the social structure provides ecological clues concerning the integration of interactions, reproduction, distributions, densities, and diel activities for not only one animal and species, but for a complex of animals interacting with each other.


A Revision Of Cryptantha Subgenus Oreocarya, Larry Charles Higgins Jun 1969

A Revision Of Cryptantha Subgenus Oreocarya, Larry Charles Higgins

Theses and Dissertations

This study is a taxonomic revision of Cryptantha subgenus Oreocarya (Boraginaceae), together with descriptions of species, synonyms, distribution maps, and discussions. The present treatment recognizes fifty-seven species and fourteen varieties, all separated by means of a comprehensive key. A history of the group, along with a discussion of the distribution, ecology, and phylogeny is presented. As a basis for the comparison of taxa much of the research has been concentrated on morphological variation in herbarium specimens. Particular attention has been directed to a study of pubescence types, branching patterns, flowers, calyces, and the fruit. The herbarium research has been correlated …


Biochemical And Morphological Analyses Of The Hordeum Jubatum-Brachyantherum-Caespitosum Hybrid Complex, Gareth Roz Babbel Jun 1969

Biochemical And Morphological Analyses Of The Hordeum Jubatum-Brachyantherum-Caespitosum Hybrid Complex, Gareth Roz Babbel

Theses and Dissertations

Hordeum jubatum L., Hordeum brachyantherum nevski, and Hordeum jubatum var. caespitosum (Scribn.) Hitchc. Plants from sites in Utah and Idaho were grown and examined in order to determine whether or not hybridization with subsequent introgression occurs among the species and if so whether there is a difference in the relative amount of gene flow between the parent species H. jubatum and H. brachyantherum in different environments. Hybridizations and morphological analyses were made using standard procedures. Biochemical analyses were made by comparing paper chromatograms of leaf extracts of plant specimens. The results indicate that in Utah populations sampled, hybridization with subsequent …


A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist May 1969

A Comparative Survey Of Soil Microfungi From Three Vegetation Types In Cedar Valley, Utah, Brent T. Wahlquist

Theses and Dissertations

Microfungi were isolated from soil samples by the soil plate method. Soil samples were collected at depths of 0-1", 1-4", and 4-8" both between and beneath the canopy of the dominant vegetation in stands of greasewood, sagebrush, and pinyon-juniper. Salinity, pH, and percent organic matter were measured for each soil sample. A total of 148 strains of fungi representing 141 species and 46 genera were isolated and identified from these alkaline soils, Few strains, including some Aspergilli, occurred only in the more saline greasewood soils, while many strains, including several Penicillia, occurred in both sagebrush and piny-on-juniper soils but were …


The Fisheries Of Deer Creek Reservoir, Utah, With Special Emphasis On The Yellow Perch (Perca Flavescens Mitchill), Gale R. Lewellen May 1969

The Fisheries Of Deer Creek Reservoir, Utah, With Special Emphasis On The Yellow Perch (Perca Flavescens Mitchill), Gale R. Lewellen

Theses and Dissertations

This thesis is concerned with the fisheries of Deer Creek Reservoir, Wasatch County, Utah, with special emphasis on the yellow perch. The study period was from May 13 to November 24, 1968. Objectives included the determination of size, age, and food habits of the yellow perch. Parasitic occurrences in the perch population by Ligula intestinalis were also recorded as well as the utilization of the perch by the fishermen. Observations on other species of fish including an analysis of rainbow trout stocking programs were also objectives of this thesis. Data was gathered by means of creel census and fish collection …


Ecology Of The Pika (Ochotona Princeps Uinta) In The Uinta Mountains, Utah, Richard D. Bates May 1969

Ecology Of The Pika (Ochotona Princeps Uinta) In The Uinta Mountains, Utah, Richard D. Bates

Theses and Dissertations

In North America, pikas (mammal genus Ochotona) are distributed throughout the western mountain ranges where they are mostly restricted to higher elevation talus slides. There are two species in North America, the Alaskan or Collared Pika (Ochotona collaris Nelson) and the American Pika (Ochotona princeps Richardson). The former is found north of 58 degrees north latitude and has no subspeciation, while the latter occurs south of 58 degrees latitude and consists of 35 subspecies isolated on various mountain ranges (Hall and Kelson 1959). In Utah there are nine subspecies, which are mostly distributed in the Wasatch range that runs northeast …


A Study Of Aquatic Fungi In Powell's Slough, Chao-Chih Hsiao May 1969

A Study Of Aquatic Fungi In Powell's Slough, Chao-Chih Hsiao

Theses and Dissertations

Aquatic fungi in-Powell's Slough were.studied in 1967 & 1968. Collections were made and water temperature, oxygen content & pH values were measured at weekly intervals. For collections, wire baskets containing substrata were submerged in water for one month. After collecting, substrata were brought to the laboratory. Identification was based on the keys of Sparrow, 1960. Aquatic fungi identified included seven orders, nine families, fifteen genera, and thirty species, from thirty-three collections of fifteen types of substrata. The substrata used in this study were: (i) fruits: apples, rose hips, plums, pears, haws; (ii) twigs: poplar, weeping willow, river birch, weeping white …


A Revision Of The Hedysarum Boreale Complex, Terry Edwin Northstrom May 1969

A Revision Of The Hedysarum Boreale Complex, Terry Edwin Northstrom

Theses and Dissertations

The Hedysarum boreale complex consists of all North American Members of the genus Hedysarum which possess free wing auricles, sub-equal calyx teeth, hidden leaflet veins, and wingless loment articles. One species, two subspecies, and three varieties are recognized. The traditional methods of comparative morphology are employed in delimiting species in the herbarium, but pertinent data from field work are also included. The somatic chromosome number was determined for all taxa, and was found in all cases to be 16. Distribution maps, illustrations, and graphical comparisons of taxa are included.


The Effect Of Pregnancy And Lactation On The Iodine Compounds In The Tissues And Plasma Of The Rat, Harry Jay Lyons Aug 1968

The Effect Of Pregnancy And Lactation On The Iodine Compounds In The Tissues And Plasma Of The Rat, Harry Jay Lyons

Theses and Dissertations

An isotopic equilibrium method was employed, based on the chronic feeding of an 125I-labeled diet of known specific activity, to determine the distribution and quantitation of endogenously labeled iodine-containing compounds in the female rat at various periods during gestation and post-parturition. A decrease was associated with gestation in the total iodine, which was significant in all extrathyroidal tissues except the brain and muscle, and a fall in thyroxine concentration which was significant in all extrathyroidal tissues except the heart. The triiodothyronine level decreased from the control values in gestation but not as consistently. There was also a significant decrease in …


Scorpions Of Utah, John D. Johnson Aug 1968

Scorpions Of Utah, John D. Johnson

Theses and Dissertations

Scorpions from Utah were collected and studied to determine species present, geographic distribution, seasonal occurrence, sex ratio, and some morphological variations associated with distribution. Nine species were identified--Anuroctonus phaeodactylus, Centruroides sculpturatus, Hadrurus arizonensis, H. spadix, Vejovis becki, V. boreus, V. confusus, V. wupatkiensis, and an undescribed species of Vejovis, subgenus Paruroctonus. Five species--C. sculpturatus, H. arizonensis, V. becki, V. confusus, and V. wupatkiensis--are reported from Utah for the first time. Most specimens were collected from May through October, with greatest numbers taken in May, June, and July. Sex ratios differed with the species. Two species--A. phaeodactylus and V. boreus--showed statistically …


Thrips Of The Sagebrush-Grass Range Community In West-Central Utah, Ward Max Tingey Aug 1968

Thrips Of The Sagebrush-Grass Range Community In West-Central Utah, Ward Max Tingey

Theses and Dissertations

Three predominant and economically important shrubs of the sagebrush-grass range community in Utah, namely big sagebrush (Artemisia tridentata Nutt.), rubber rabbitbrush (Chrysothamnus nauseosus (Pall.) Britt.), antelope bitterbrush (Purshia tridentata (Pursh) DC), and a widely re-seeded range grass, crested wheatgrass (Agropyron cristatum (L.) Gaertn.) were sampled during the summers of 1966 and 1967, and yielded twenty species of thrips. Three species (Anaphothrips tricolor Moulton, Chirothrips aculeatus Bagnall, Chirothrips simplex Hood) were new distributional records for Utah. Seven species (Frankliniella n. sp. #1, Frankliniella n. sp. #2, Haplothrips n. sp., Leptothrips n. sp., Oedaleothrips n. sp., Sericothrips n. sp. #1, Sericothrips n. …


The Ecology And Life History Of Sceloporus Occidentalis Longipes Baird On Rainier Mesa At Nevada Test Site, James Mark Hopkin Aug 1968

The Ecology And Life History Of Sceloporus Occidentalis Longipes Baird On Rainier Mesa At Nevada Test Site, James Mark Hopkin

Theses and Dissertations

The study was undertaken to learn the life history of Sceloporus occidentalis longipes and its environmental adaptations on a high plateau (Rainier Mesa) with an elevation of 2,286 meters, at the Atomic Energy Commission's Nevada Test Site in Nye County, Nevada. The lizards emerge from hibernation in April with the males preceeding the females by a period of one to two weeks or more. Mating occurs in late April, May, and perhaps early June. Eggs are laid between 10 June and 15 July. Clutches of 9 to 15 eggs are laid with the younger females usually laying 9 eggs. No …


Overwintering Sites And Winter Mortality Rates Of Certain Predaceous Mites In Central Utah Orchards (Phytoseiidae: Typhlodromus), John Wayne Leetham Aug 1968

Overwintering Sites And Winter Mortality Rates Of Certain Predaceous Mites In Central Utah Orchards (Phytoseiidae: Typhlodromus), John Wayne Leetham

Theses and Dissertations

The overwintering habitats and winter mortality rates of predaceous mites (Phytoseiidae: Typhlodromus) were investigated during three successive winters, 1965-66, 1966-67, and 1967-68. Three species were predominant in derelict apple orchards, Typhlodromus mcgregori Chant on twigs and spurs and rough bark of scaffold limbs and trunk, Typhlodromus occidentalis Nesbitt on rough bark of scaffold limbs and trunk, and Amblyseius cucumeris Oudemans in ground cover. Other species (Typhlodromus columbiensis Chant, Typhlodromus caudiglans Schuster, Amblyseius fallacis (Garman), Amblyseius ovatus (Garman), Amblyseius floridanus (Muma), and Amblyseius rosellus Chant) were collected only incidentally. Substantial numbers of T. mcgregori and T. occidentalis were found to fall …


Nesting Ecology Of The Ferruginous Hawk (Buteo Regalis) In West-Central Utah, John Bradford Weston Aug 1968

Nesting Ecology Of The Ferruginous Hawk (Buteo Regalis) In West-Central Utah, John Bradford Weston

Theses and Dissertations

During the spring seasons of 1967 and 1968 ecological studies were made of nesting Ferruginou.s Hawks (Buteo regalis) in a 325 square mile area in west-central Utah. In the springs of 1967 and 1968 a systematic search was conducted throughout the study area for Ferruginous Hawk nests. When active nests were located they were kept under observation throughout the study. The density of nesting pairs in 1967 and 1968 ranged from 7 to 15.4 square miles per pair. An annual seasonal displacement was exhibited, with Ferruginous Hawks being present in the study area only during the nesting season, which lasted …


Vegetational Changes In A Mountain Brush Community Of Utah During Eighteen Years, Robert J. Eastmond Aug 1968

Vegetational Changes In A Mountain Brush Community Of Utah During Eighteen Years, Robert J. Eastmond

Theses and Dissertations

This vegetational analysis is concerned with changes which have cocurred since 1949 in a mountain brush community within an exclosure in the central Wasatch Mountains. The exclosure, established in 1949, is located in Pole Canyon on lower Provo Canyon. Two major studies have been conducted previously, but it has been nine years since the last intensive work was done. Several major changes occurring during the eighteen year period are evident and are described.


Factors Influencing Production Of Flower Stalks In Agropyron Cristatum (L.) Gaertn, Neil C. Frischknecht Aug 1968

Factors Influencing Production Of Flower Stalks In Agropyron Cristatum (L.) Gaertn, Neil C. Frischknecht

Theses and Dissertations

A study was made of factors that influence production of different numbers of flower stalks of crested wheatgrass on grazed and ungrazed areas. Both laboratory and field studies were made. Greatest response in flower stalk production resulted from application of nitrogen in the field, amounting to an increase of from 5 to 10 times the numbers of flower stalks on untreated areas. Responses of plants in the greenhouse supported these results. Plants grown in the dark indicated that higher carbohydrate reserves existed in ungrazed than in grazed plants. It was concluded that a high carbohydrate-low nitrogen balance was the primary …


A Study Of Multiple Embryo Development In The Netleaf Hackberry (Celtis Reticulata), Gary Porter Lawrence Aug 1968

A Study Of Multiple Embryo Development In The Netleaf Hackberry (Celtis Reticulata), Gary Porter Lawrence

Theses and Dissertations

Previous research has shown that polyembryony occurs in many species of the Ulmaceae. The purpose of this study was to determine the method of multiple embryo formation in netleaf hackberry, Celtis reticulata Torr. Collections of specimens were made throughout a two-year period. Collections were begun in early spring while the trees were still in the bud state. Collections were continued regularly throughout the growing season. The collections were preserved in FAA solution and were prepared for microscopic examination as follows: (1) The tertiary butyl paraffin method was used for dehydrating and embedding. (2) Sectioning was done on a rotary microtome …


Inhibition Of Planarian Regeneration, Douglas Pierre Bingham Aug 1968

Inhibition Of Planarian Regeneration, Douglas Pierre Bingham

Theses and Dissertations

This thesis describes my study of inhibition of brain regeneration in planaria. The flatworm (Dugesia tigrina) possesses a remarkable ability to regenerate lost parts, including the head. The primary objective of my study was to determine the extent to which an inhibiting substance, located in the head, would prevent regeneration of the brain. A secondary objective was to study whether DMSO (Dimethyl Sulfoxide) would facilitate the action of the inhibitor.


Osteological And Myological Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Noble (Family Teiidae), Don Lowell Fisher Aug 1968

Osteological And Myological Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Noble (Family Teiidae), Don Lowell Fisher

Theses and Dissertations

There has long been a need for a comparative study of the osteological and myological structures of the reptilian family Teiidaeo This present study is organized to increase our understanding of the anatomical features of the head and thorax regions of two members of distinct phylogenetic branches of the family Teiidaeo The two genera discussed are Cnemidophorus and Ameiva.


A Study Of The Channel Catfish, Ictalurus Punctatus (Rafinesque), In Mud Lake, Utah, Horst Friedrich Siewert Aug 1968

A Study Of The Channel Catfish, Ictalurus Punctatus (Rafinesque), In Mud Lake, Utah, Horst Friedrich Siewert

Theses and Dissertations

From June to November 1967, a study on channel catfish, lctalurus punctatus (Rafinesque), in Mud Lake, Utah Co., Utah was undertaken. The objectives were (I) to estimate if channel catfish are increasing or decreasing in Mud Lake, (2) to estimate the mean size of adult channel catfish in Mud lake, (3) to determine which environmental factors effect the catch of channel catfish, and (4) to determine if the channel catfish in Mud lake are residents year round. A total of 310 mature channel catfish and 920 carp were collected with four hoop nets. Two fingerling were captured by seining. Ratios …


Field Observations And Laboratory Studies On Growth And Tillering In Seedlings Of Oryzopsis Hymenoides As Affected By Selected Environmental Factors Of The Sand Dunes Of Lynndyl, Utah, Leopold B. Smigelski Aug 1968

Field Observations And Laboratory Studies On Growth And Tillering In Seedlings Of Oryzopsis Hymenoides As Affected By Selected Environmental Factors Of The Sand Dunes Of Lynndyl, Utah, Leopold B. Smigelski

Theses and Dissertations

Seedlings of Indian rice grass Oryzopsis hvmenoides (Roem. & Shult.) Ricker. were studied to determine the effect of soil moisture, photoperiod, depth of burial of germinated grains, temperature, and the rate of soil accumulation on seedling growth and tillering. The study was performed in two phases: Field observations and laboratory studies. Field observations were made on a system of sand dunes located northwest of Lynndyl, Utah. General observations were made from January, 1966 to May, 1968.