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Distribution Of The Native Trees Of Utah, Kimball S. Erdman Sep 1970

Distribution Of The Native Trees Of Utah, Kimball S. Erdman

Brigham Young University Science Bulletin, Biological Series

Although botanists have been actively collecting in Utah for well over a century, the distribution of many plants are as yet imperfectly known. This is, in part, due to the scattered nature of Utah herbarium material. Also the terrain of the state has impeded collection in more rugged and remote areas. The present study gathers together the data from the major collections of native Utah trees and clarifies our present understanding of tree distributions in the state. The older collection records have been extensively supplemented by the field work of the author and other botanists.

The great diversity of environments …


Front Matter, Vol. 11 No. 3 Sep 1970

Front Matter, Vol. 11 No. 3

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


The Effect Of The Parasite Hymenolepis Diminuta On Iodine Economy In The Rat, David Gourdon Holmes Aug 1970

The Effect Of The Parasite Hymenolepis Diminuta On Iodine Economy In The Rat, David Gourdon Holmes

Theses and Dissertations

A balance of iodine within the rats is important for the maintenance of normal thyroid function. Because of Hymenolepis d[imi]nuta's affinity for certain nutrients, it may upset norma[l] iodine balance in the rat. To determine this, tapeworm-infected and non-infected rats were given 125Iodide orally and the percent uptake of iodide by the thyroid and the amount of radioac[tiv]ity in the tapeworms was determined. The percent distribution of the radio-iodinated compounds in the thyroid, tapeworms and feces was also determined. These procedures were repeated except 125Thyroxine was administered orally. There was a decrease in percent iod[id]e uptake by thyroids of tapeworm-infected …


Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield Aug 1970

Asexual Reproduction In Planaria Characteristics Of The Inhibitor(S), Linda Gail Sheffield

Theses and Dissertations

A study was made of the postulated fission-inhibiting substance located in the cephalic region of Dugesia dorotocephala. Rearing decapitated planaria in four different concentrations (25, 50, 75 or 100 ug/ml) of head or whole body extract resulted in a positive correlation between the inhibition of fission rate and the concentration of extract. The difference in inhibitory activity between the two types of extracts was three percent at maximum. The inhibitory substance was partially inactivated at 60° C. There was a direct correlation between the length of time that the extract was heated and the inactivation of inhibitor. The active substance …


A Study Of The Electrophoretic Patterns Of Blood Serum Proteins From Two Populations Of Mountain Whitefish (Prosopium Williamsoni), Fred Richard Hansen Aug 1970

A Study Of The Electrophoretic Patterns Of Blood Serum Proteins From Two Populations Of Mountain Whitefish (Prosopium Williamsoni), Fred Richard Hansen

Theses and Dissertations

Electrophoretic patterns on polyacrylamide gels of blood serum proteins from 74 mountain whitefish (Prosopium williamsoni Girard) were examined for differences as they pertained to two geographically isolated populations, age, and sex. Serum samples were acquired from two supposedly isolated populations, the lower Provo River and the lower Weber River. Comparisons among gels were made on the basis of protein distribution as indicated by number of fractions and their density. Serum proteins showed marked intraspecific differences between the males as well as the females of each population. No variations were found which could be attributed to degree of maturity. Definite pattern …


Evolution Of The Iguanine Lizards (Sauria, Iguanidae) As Determined By Osteological And Myological Characters, David F. Avery Aug 1970

Evolution Of The Iguanine Lizards (Sauria, Iguanidae) As Determined By Osteological And Myological Characters, David F. Avery

Theses and Dissertations

The family Iguanidae is almost completely restricted to the Western Hemisphere with its main radiations occurring in North and South America. There are also representatives on Fiji, Tonga and the Galapagos Islands, in the Pacific Ocean. Distantly related forms are also found on Madagascar off the Southeastern Coast of Africa. Although the iguanid lizards are familiar to most scientists interested in the tropics, their anatomy and evolution is poorly understood.


Effects Of X-Irradiation On The Brain Of White Rats, Bernell K. Dalley Aug 1970

Effects Of X-Irradiation On The Brain Of White Rats, Bernell K. Dalley

Theses and Dissertations

With the advent of the atomic age, a great deal of attention has been given to the effects of radiation of various types on the living organism. Some emphasis was placed also on the particular effects damaging radiation has on the central nervous system. Of particular importance was the dis -covery of the high resistance to irradiation exhibited by the central nervous system, and the observation of a latent period after exposure, during which the individual appears normal, followed by deterioration and death. Explan - ations of this unique reaction have caused some controversy and, currently, one of two theories …


The Effects Of Various Treatments On Thiamin Diphosphate And Total Thiamin Levels Of Rat Tissues, Dong Hwa Park Aug 1970

The Effects Of Various Treatments On Thiamin Diphosphate And Total Thiamin Levels Of Rat Tissues, Dong Hwa Park

Theses and Dissertations

Tissue thiamin diphosphate was assayed enzymatically utilizing purified brewer's yeast apotransketolase. With this assay ten uumoles of thiamin diphosphate could be detected. Total thiamin was fluorometrically measured. For one to three days rats were placed under conditions of stress, consisting of loud noise treatment, emotional stress, deprivation of paradoxical sleep, and swimming to exhaustion, respectively. The body weight was markedly decreased at the end of the respective experimental periods except with the loud noise treated group, compared with the corresponding controls. Following two to three such consecutive treatments, the adrenal weight also showed a significant increase. Thiamin diphosphate and total …


The Effects Of Herbicide Applications On The Animal Populations Of Aspen Communities, Carl Eugene Wadsworth Aug 1970

The Effects Of Herbicide Applications On The Animal Populations Of Aspen Communities, Carl Eugene Wadsworth

Theses and Dissertations

Approximately 475 acres of aspen, oak brush, and grass-forb-shrub communities were treated with herbicides. The populations of arthropods, birds, and mammals were investigated on treated and untreated areas and the results were compared. There was no difference between soil arthropod populations on treated and untreated aspen plots but a significant increase in these populations on treated meadow plots. The foliage insect populations were significantly lower on the treated aspen plots but were significantly higher on the treated meadow plots. The aquatic invertebrates were not affected by the treatments. Bird populations ware lower in the treated area during the nesting season …


Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald Aug 1970

Asexual Reproduction In Planaria Studies On Inhibition, Hal R. Fitzgerald

Theses and Dissertations

The invertebrates display several methods of asexual reproduction, such as fission and gemnule formation and budding (Hay, 1966). Planaria reproduce asexually only by fission.


Aquatic And Semi-Aquatic Plant Communities Of Utah Lake, Robert E. Coombs Aug 1970

Aquatic And Semi-Aquatic Plant Communities Of Utah Lake, Robert E. Coombs

Theses and Dissertations

The aquatic and semi-aquatic plant communities of Utah Lake, Utah County, Utah are discussed. This discussion includes the methods of describing and delimiting the major vascular plant communities, the descriptions of the present existent communities, and the determination of the vegetational changes, particularly since 1925. The vegetation around Utah Lake is divided into plant communities. Each community is discussed using: (a) quantitative data, (b) field observations, (c) general and specific locations of the community, and (d) interrelationships and trends of the community. Historical vegetational changes of Utah Lake plant communities are discussed. In this discussion, the plant communities described by …


A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks, Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash Jul 1970

A Comparative Study Of The Head And Thoracic Osteology And Myology Of The Skinks, Eumeces Gilberti Van Denburgh And Eumeces Skiltonianus (Baird And Girard), David F. Nash

Theses and Dissertations

Further clarification of the taxonomic and phylogenetic relationships of Eumeces gilberti and Eumeces skiltonianus is achieved by the comparisons of the skull, mandible elements, and the anterior myology of these two species. Figures are provided to compliment the descriptions. The study confirms their close relationship and few differences are observed. E. skiltonianus, however, appears to have more anatomical plasticity which suggests that E. gilberti may have arisen from the former.


Front Matter, Vol. 30 No. 2 Jun 1970

Front Matter, Vol. 30 No. 2

Great Basin Naturalist

No abstract provided.


Richardson's Ground Squirrel (Spermophilus Richardsonii) In The Laramie Basin, Wyoming, Tim W. Clark Jun 1970

Richardson's Ground Squirrel (Spermophilus Richardsonii) In The Laramie Basin, Wyoming, Tim W. Clark

Great Basin Naturalist

No abstract provided.


Osteological And Mylogical Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Nobel (Family Teiidae), Don Lowell Fisher, Wilmer W. Tanner Jun 1970

Osteological And Mylogical Comparisons Of The Head And Thorax Regions Of Cnemidophorus Tigris Septentrionalis Burger And Ameiva Undulata Parva Barbour And Nobel (Family Teiidae), Don Lowell Fisher, Wilmer W. Tanner

Brigham Young University Science Bulletin, Biological Series

The anterior osteological elements of the skull, lower jaw, and wrist along with the anterior myological characters discussed and figured in this report suggest that A. u. parva and C. t. septentrionalis are members of distinct groups which can be differentiated by internal morphologic characters. Although comparisons were restricted to highly geographically separated individuals of the same family, their general body form and structure appear to be similar.

A great number of anatomical structures are shared in common, but the significant differences between them include:

1. General skull appearance. The skull of C. is generally lighter, that is the bones …


Pinyon-Juniper Succession After Natural Fires On Residual Soils Of Mesa Verde, Colorado, James A. Erdman Jun 1970

Pinyon-Juniper Succession After Natural Fires On Residual Soils Of Mesa Verde, Colorado, James A. Erdman

Brigham Young University Science Bulletin, Biological Series

A mountain brush vegetation typified by Gambel oak (Quercus gambelii) and serviceberry (Amelanchier utahensis) dominates the uplands of Mesa Verde National Park. There is evidence that this brush element is a successional stage that has been maintained by repeated natural fires in a large part of the Mesa Verde landscape. This study was conducted to determine the role of fire in the region's ecology, the nature of the climax pinyon pine (Pinus edulis) and Utah juniper (Juniperus osteosperma) vegetation, and the major successional stages that lead to the climax condition.

Three postburn …


End Matter, Vol. 11 No. 2 Jun 1970

End Matter, Vol. 11 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle Jun 1970

Preparation Of New Amino-, Thio-, And Sulfonyladamantane Derivatives, Joseph Craig Argyle

Theses and Dissertations

Various synthetic schemes were used to prepare a number of new amino-thio- and sulfonyladamantane compounds. By a nucleophilic substitution on 1-bromoadamantane, 1-(p-nitrophenylthio)adamantane was prepared from p-nitrothiophenol; the amino- and sulfonyl- derivatives of this compound were also prepared. Silver tosylate was used to generate the 1-adamantyl carbonium ion from 1-bromoadamantane in a synthetically useful procedure for preparing 1-adamantylamides from nitriles. Three 1-(1-adamantylcarbinyl)-2,5-dialkylpyrroles were prepared by Knorr-Paal reactions and reduced to the corresponding pyrrolidines. Thio- and aminomethyl 1-adamantyl ketones were prepared from methyl and bromomethyl 1-adamantyl ketones, respectively. Aliphatic and aromatic oxiranes were reacted with 1-aminoadamantane in a bomb at elevated temperatures …


Front Matter, Vol. 11 No. 2 Jun 1970

Front Matter, Vol. 11 No. 2

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


End Matter, Vol. 11 No. 1 Jun 1970

End Matter, Vol. 11 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


Calorigenic Effects Of Thyroxine And Triiodothyronine On Rat Diaphragm., Robert Lee Chambers Jun 1970

Calorigenic Effects Of Thyroxine And Triiodothyronine On Rat Diaphragm., Robert Lee Chambers

Theses and Dissertations

Since the isolation of triiodothyronine (T3) by Pitt-Rivers and Gross (1953) several questions as to its role as a thyroid hormone arose. Does T3 have the same or different actions than that of thyroxine (T4 )? Is T3 an emergency hormone, since its synthesis relative to T4 is greatly increased during periods of low iodine intake and its response time is I/5th that of T4 (Ackerman and Arons, 1958)? Are there any interactions modifying their respective actions?


The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish Jun 1970

The Synthesis And Properties Of New Potentially Chemotheraputic [Sic] Pteridine Derivatives, Walter Wesley Parish

Theses and Dissertations

A new general synthetic method for the preparation of 6-thiopteridines has been developed. The method involves the addition of thiols to intermediate pyrimidine nitrones formed in situ by the reaction of 4-amino-5-nitrosopyrimidines with pyridinium-activated acetonitriles, acetates, acetophenones, and other methylketones. Ca. forty new pteridines were prepared by this method. The preparation of six new 6-pteridinyl ketones, two new 6- pteridinyl ketone thiosemicarbazones, and two new 6-sulfonylpteridines and their 4-acetamido derivatives is also reported. 4-Acetamido-2- amino-7-phenylpteridine 5-oxide was prepared by the reaction of 2- amino-4,6-diacetamido-5-nitrosopyrimidine with either phenylsulfonyl-acetophenone or phenacylpyridinium bromide. Evidence relating to the structure of the acylated 4-amino-5- nitrosopyrimidines …


Front Matter, Vol. 11 No. 1 Jun 1970

Front Matter, Vol. 11 No. 1

Brigham Young University Science Bulletin, Biological Series

No abstract provided.


A Feasibility Study Of The Application Of Bondgraph Modeling And Computerized Nonlinear Model Parameter Identification Techniques To The Cardiovascular System, Randall L. Taylor Jun 1970

A Feasibility Study Of The Application Of Bondgraph Modeling And Computerized Nonlinear Model Parameter Identification Techniques To The Cardiovascular System, Randall L. Taylor

Theses and Dissertations

Recent years have witnessed an increasing trend for people in the medical and engineering professions to couple their talents in a more united effort to better understand the functioning of the human body. This union of technologies has meant the introduction of new viewpoints and techniques in the field of physiological research. The engineers' basic tool, mathematical modeling, has perhaps been one of the most noticeable additions. There has been a significant amount of work done in recent years along these lines of deriving mathematical models to express the functioning of a subsystem of the body, and then, using analog, …


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 …


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 …


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 …


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 …


Church Beginnings In China, R. Lanier Britsch Apr 1970

Church Beginnings In China, R. Lanier Britsch

BYU Studies

No abstract provided.


Meeting The Challenges Of The Latter-Day Saints In Vietnam, Desmond L. Anderson Apr 1970

Meeting The Challenges Of The Latter-Day Saints In Vietnam, Desmond L. Anderson

BYU Studies

No abstract provided.