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Support Systems Of Mexican-American Women And Their Attitudes Regarding Infant Feeding, Susan Marie Krantz May 1981

Support Systems Of Mexican-American Women And Their Attitudes Regarding Infant Feeding, Susan Marie Krantz

Loma Linda University Electronic Theses, Dissertations & Projects

This was a descriptive study of 37 recently migrated to the United States, Spanish-speaking, Mexican-American women. Attitudes and support systems associated with their choice to breast or bottle feed their infants were studied. The purpose of this research was to answer the following questions:

1. What are the differences in the attitudes of Mexican- American primiparas who choose to breast feed and those who choose to bottle feed?

2. What are the differences in the practice, recommendations, and proximity of location of significant members of the women's support systems?

Twenty-one breast feeders and 16 bottle feeders were interviewed in Spanish …


Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek May 1981

Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Blacksmith Formation of Middle Cambrian (Albertan) age was studied in southeastern Idaho and northernmost Utah. Lithology and sedimentary structures were compared with modern environments and ancient rocks to determine environments of deposition, paleo-geography, diagenetic alterations and patterns of dolomitization.

The Blacksmith Formation can be divided into five basic rock types. Rock type A has cryptalgalaminae, mudcracks, and lacks bioturbation. Rock type A is inferred to have been deposited in the upper intertidal to supratidal environment. Rock type B is extremely dolomitized and brecciated. It is inferred that rock type B was deposited in the upper intertidal to supratidal environment. …


Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza May 1981

Some Morphological And Chemical Responses Of Blackbrush (Coleogyne Ramosissima) To Goat Browsing: Influences On Dietary Blackbrush Selection By Goats And Cattle, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Domestic goats were used to modify the growth form of blackbrush, a spinescent shrub occurring in nearly monospecific stands on several million hectares of rangeland in the southwestern United States. The objective of this research was to evaluate goat browsing as a means of improving these rangelands for cattle. Winter goat browsing stimulated spring twig growth from basal and axillary buds which resulted in increased production.

Twig production by heavily browsed plants (>95 percent removal of current season's twigs) was a function of precipitation, soil depth, branch location on the plant, and period of rest after browsing. As precipitation …


Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk May 1981

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …


Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman May 1981

Effect Of Mild Water Stress And Enhanced Ultraviolet-B Irradiation On Leaf Growth Of Rumex Obtusifolius L. And Rumex Patientia L. (Polygonaceae)., Steve R. Holman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaves of Rumex obtusifolius L. and R. patientia L.were exposed to combinations of mild water stress and enhanced ultraviolet-B irradiation during their ontogeny. Two UV-B treatments (enhanced UV-B and control) and three water stress treatments (-0.0 MPa, -0.2 MPa and -0.4 MPa rooting medium matric potentials) were employed. The impact of the stress interaction was assessed on the basis of changes in leaf area, average adaxial epidermal cell size, and total number of adaxial epidermal cells per leaf. Although the level of UV-B irradiation applied was insufficient to significantly alter leaf growth at any given water stress, UV-B did interact …


The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad May 1981

The Energy Expenditure Of Heifers Grazing Crested Wheatgrass Rangeland In West-Central Utah, Kris M. Havstad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The free-roaming ruminant requires energy for the demands of vii grazing, traveling and thermoregulation that are not required by its confined counterpart. Literature estimates of these additional costs range from 10 to 170 percent above maintenance. The uncertain magnitude of this increased demand and the factors that contribute to it impede the ability of the rangeland ruminant nutritionist to establish guidelines for the energy requirements of the free-roaming herbivore. This study was designed to estimate the energy expenditure of yearling Angus heifers while grazing a declining supply of available crested wheatgrass forage (Agropyron cristatum) on rangeland in west-central …


Lifestyle As A Determinant Of Participation Among Dispersed Forest Recreationists, John R. Butler May 1981

Lifestyle As A Determinant Of Participation Among Dispersed Forest Recreationists, John R. Butler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study assesses the usefulness of lifestyle as a determinant of outdoor recreation behavior. Two objectives of the study are: (1) develop an operationalized concept of lifestyle that is based on theory, and (2) apply this concept in a model which uses lifestyle as a variable influencing recreation behavior.

The first objective was approached through an integrative review of the literature. Lifestyle was set in context of cultural theory. The basic postulate of the proposed theory of lifestyle is: If an individual's lifestyle is similar to that of another, certain social psychological processes are similar. Therefore, their patterns of needs, …


Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat May 1981

Seasonal Temperature Preference Of Adult Mountain Whitefish, Prosopium Williamsoni, Jean M. Ihnat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Temperatures selected seasonally by adult mountain whitefish were measured in the laboratory in a horizontal gradient. Final preferendum estimates, based on acute (3-hour) preference tests conducted with fish acclimated to 5, 10, and 15 C each season, were 17.7 C (pre-spawning), 11.9 C (post-spawning), 9.9 C (winter), and 16.3 C (spring). Seasonal influence on temperature selection was evident on the basis of differences in final preferenda, covariance analysis of responses of laboratory-acclimated fish, and temperature selection by fish held at ambient river temperatures. Post-spawning and winter groups selected lower temperatures than did pre-spawning and spring groups. Pre-spawning fish selected temperatures …


Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines May 1981

Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Community succession, the orderly changes a community experiences with time, is considered to be the result of either autogenic or allogenic factors working singularly or in combination. It has been further suggested that, as communities undergo succession, certain biological parameters change in a predictable manner. Examination of members 2 through 4 of the Mississippian (Kinderhook-Osage) Lodgepole Formation of Samaria Mountain, Idaho provides a means to evaluate these concepts.

Within the study section comprised of 125 beds (61.5 m thick), four rock types are recognized. These include: (1) fossiliferous wackestone (78% of beds), which ranges in color from dark-gray (N3) to …


Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin May 1981

Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was designed to accomplish two primary objectives: (1) to compare two test methods commonly used to evaluate toxicity of inhaled air pollutants, and (2) to observe the response as measured by each of the methods, of pulmonary alveolar macrophages exposed to 2μg hexavalent chromium.

The first method evaluated featured use of intratracheal injections to simulate live inhalation exposures, and the second required exposure of macrophages cultured on petri plates. Pulmonary alveolar macrophages harvested from Long Evans rats were used. The two cell function parameters measured in the evaluations were chemiluminescence and oxygen consumption (which was determined for cells …


The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant May 1981

The Transport And Intracellular Distribution Of Iron In The Basidiomycete, Ustilago Sphaerogena, Charles W. Passavant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The transport and intracellular distribution of iron in Ustilago sphaerogena via the native siderochrome ferrichrome A has been examined. Evidence is presented which suggests the involvement of deferriferrichrome in iron transport when the metal is supplied to the cell as ferrichrome A. This process requires both oxygen and ATP synthesis and may require a transmembrane electrochemical gradient. Once inside the cell, iron derived from ferrichrome A is rapidly distributed, with a major fraction found in the mitochondria, presumably as heme.

The kinetics of ferrichrome and ferrichrome A uptake have also been investigated. The Km of transport of ferrichrome was …


The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney Apr 1981

The Rhode Island Quahogger: Candidate For The List Of Endangered Species?, James M. Korney

Marine Affairs Theses and Major Papers

It is the hypothesis of this paper that today the livelihood of the independent Narragansett Bay quahogger is faced with two potentially dangerous threats; water pollution in upper Narragansett Bay and the prospect of an expanding aquaculture industry in the lower bay. Unless the state of Rhode Island properly interprets and enforces existing state legislation to protect the quahoggers interests, his very livelihood will be jeoprodized. This paper will examine the legal, political, economic, and environmental affects of water pollution in upper Narragansett Bay and an expanding aquaculture industry in the lower bay in their relation to the Rhode Island …


The Impact Of The Federal Water Pollution Control Act On The Discharge Of Sanitary Waste From United States Navy Ships, William G. Fidyk Apr 1981

The Impact Of The Federal Water Pollution Control Act On The Discharge Of Sanitary Waste From United States Navy Ships, William G. Fidyk

Marine Affairs Theses and Major Papers

During the late 1960's and early 1970's several significant pieces of environmental legislation were enacted. These pieces of legislation were designed to restore, improve, preserve and protect our natural resources. The legislation with the most impact on the United State Navy and Naval vessels has been the Federal Water Pollution Control Act. In order to meet the statutory requirements of the Clean Water Act, the United States Navy had to embark on a program to: modify existing vessels with Marine Sanitation Devices (MSD's) and install such devices on new construction ships.


Municipal Sewage Treatment: Problems And Considerations, George R. Johnson Apr 1981

Municipal Sewage Treatment: Problems And Considerations, George R. Johnson

Marine Affairs Theses and Major Papers

The coastal areas are vital to the economic and physical well being of the United States. Virtually every facet of our way of life is related in some fashion to these coastal areas. Ocean borne transportation moves not only vast quantities of raw materials, but also many of the intermediate and final products that are then manufactured to their related market areas. Fisheries provide vast amounts of food and employment for many of our people. In addition, the coasts are a continuing source of enjoyment and recreation for millions of our citizens. Coastal waters provide much of the water necessary …


The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1981 [Program, 93th Meeting], Iowa Academy Of Science Apr 1981

The Annual Meeting Of The Iowa Academy Of Science April 24-25, 1981 [Program, 93th Meeting], Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


93rd Session Iowa Academy Of Science Awards Luncheon, April 24, 1981, Iowa Academy Of Science Apr 1981

93rd Session Iowa Academy Of Science Awards Luncheon, April 24, 1981, Iowa Academy Of Science

Iowa Academy of Science Documents

Program:

--- Introduction of Head Table - Donald M. Huffman, Central College, President, Iowa Academy of Science
--- Recognition of students participating in various state-wide activities - Gary Downs, Chair, Student Programs Committee
--- Presentation of students selected to present papers at the 1981 Iowa Academy Meeting and announcement of those selected to represent Iowa at the American Junior Academy of Science Meeting, Washington DC, January 1982 - Joe Moore, Director, Iowa Junior Academy of Science
--- Presentation of the Excellence in Science Teaching Award in Biology, Chemistry, Physics, Earth Science, Elementary Science, Junior High Science - David McCalley, University …


Abstracts Of Papers, 93rd Session, Iowa Academy Of Science, April 24-25, 1981, Iowa Academy Of Science Apr 1981

Abstracts Of Papers, 93rd Session, Iowa Academy Of Science, April 24-25, 1981, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


The Viability Of Imported Liquified Natural Gas As An Energy Resource, Richard L. Dick Apr 1981

The Viability Of Imported Liquified Natural Gas As An Energy Resource, Richard L. Dick

Marine Affairs Theses and Major Papers

As the United States enters the 1980's, the need for secure and efficient energy sources is rapidly moving to the forefront of our foreign and domestic policies. It is apparent that our existence, as well as that of our allies, is closely tied to the ability to secure energy resources. The importation of Liquified Natural Gas (LNG), by specially designed ships, from oil exporting nations to energy consuming nations has been a highly touted energy resource. United States importation of LNG is not a cost effective energy resource due to: (1) dependence on foreign sources, (2) transportation costs including "hidden" …


Theory And Intuition, E. A. Mccullough Jr. Apr 1981

Theory And Intuition, E. A. Mccullough Jr.

Faculty Honor Lectures

Among the practitioners of science are people who are called theorists , and this lecture is concerned with the question, Just what is it that a theorist does?

If an experimentalist does experiments, then a theorist presumably does theories. What is a theory? My dictionary defines it as ". . . a system of assumptions, accepted principles, or rules of pro· cedure devised to analyze, predict or otherwise explain the nature or behavior of a specified set of phenomena."

Those who now understand perfectly what a theorist does may stop reading here because everything that follows will be superfluous. For …


A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris Apr 1981

A Comparison Of Reproductive Strategies Among Marine Snakes, Cliff A. Lemen, Harold K. Voris

School of Natural Resources: Faculty Publications

(1) Gravid females representing fourteen species of marine snakes were collected from four localities along the coast of Malaysia in 1975. The average clutch size ranged from 2.9 to 17.8 but most species had between three and seven young. The number of young produced and the size of gravid Lapemis hardwickii differed significantly at two sites in the Straits of Malacca. Eight species showed a significantly positive relationship between the number of oviducal eggs and female weight. The rate of infertility among ten species ranged from 4.5 to 20%.

(2) Sex ratios in the collections varied significantly through time and …


Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon Apr 1981

Maine's Whitewater Rapids And Their Relevance To The Critical Areas Program, Janet Mcmahon

Maine Collection

Maine's Whitewater Rapids and Their Relevance to the Critical Areas Program

by Janet McMahon

Planning Report No. 74, Critical Areas Program, 184 State St., Augusta, Maine,

April, 1981 (additions made in October, 1981). Reprinted July, 1983.

Contents: Introduction / Natural History of Whitewater Rapids / Methods / Criteria / Results / Conclusions / General Evaluation of Whitewater Rapids for Inclusion on the Register of Critical Areas / Bibliography / Action Plan


Mouthpart Morphology And Feeding Strategies Of The Commensal Amphipod, Anamixis Hanseni Stebbing, James Darwin Thomas, George W. Taylor Apr 1981

Mouthpart Morphology And Feeding Strategies Of The Commensal Amphipod, Anamixis Hanseni Stebbing, James Darwin Thomas, George W. Taylor

Marine & Environmental Sciences Faculty Articles

The lack of the information on the biology of the commensal amphipod family Anamixidae prompted investigations into mouthpart ultrastructure, feeding biology, and host specificity of Anamixis hanseni Stebbing, 1897. Earlier investigators presented conflicting reports on the structural composition of the buccal region and feeding modes in anamixids. Scanning electron microscope analysis of A. hanseni showed a complete set of mouthparts to be present, although much modified and reduced, except for the well-developed maxilliped palps. Feeding is not parasitic (piercing and sucking host tissue) as previously believed but is accomplished while A. hanseni rests inside its host. Minute food particles are …


Chemistry Of Organic N-Chloramines, Formation Of Arenesulfonamides By Derivatization Of Organic N-Chloramine With Sodium Arenesulfinate, Katherine F. Bowdring Apr 1981

Chemistry Of Organic N-Chloramines, Formation Of Arenesulfonamides By Derivatization Of Organic N-Chloramine With Sodium Arenesulfinate, Katherine F. Bowdring

Chemistry & Biochemistry Theses & Dissertations

Organic N-chloramines are recognized by-products of chlorinated water systems. Because of their chemistry, none have been isolated or identified.

This paper discusses a method for the derivatization of the organic N-chloramines based on a nucleophillic substitution mechanism. N-Chloro derivatives of amines of various structures were studied including primary and secondary aliphatic amines, as well as amino acids. The effect of the presence of other functional groups including aromatic and unsaturated systems was investigated.

Derivatization was done by three different methods, one involving derivatization of the pure N-chloramine, and two involving derivatizations of the N-chloramine generated in situ. Seventeen arenesulfonamides have …


High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan Apr 1981

High Performance Liquid Chromatographic Analysis Of Biogenic Amines, Thais Edwina Ahrendt Keegan

Chemistry & Biochemistry Theses & Dissertations

The objectives of this research were to develop a sensitive method for separation and quantitation of biogenic amines and to apply that procedure by monitoring neurochemical changes resulting from stimuli to the test system.

Primary aromatic amines were derivatized with o-phthalaldehyde-mercaptoethanol prior to chromatography, Separation of the fluorescent adduct was achieved using a μBondapak/ phenyl reversed-phase column and a two-step gradient of methanol:0.08 M acetic acid, pH J.O. Fluorescence was monitored using a J40 nm excitation energy and an emission filter which transmits radiation greater than 400 nm (50% T at 418 nanometers).

Following optimization of the chromatographic conditions, studies …


Palynological Correlation Of The Kentucky No. 12 Coal, Gerald E. Vyhmeister Apr 1981

Palynological Correlation Of The Kentucky No. 12 Coal, Gerald E. Vyhmeister

Loma Linda University Electronic Theses, Dissertations & Projects

In attempting to analyze the depositional environment for the Kentucky No. 12 Coal three columns were sampled from a 1 km area. The columns yielded 76 miospore species belonging to 33 genera, and representing in decreasing order of abundance, arborescent lycopods, tree ferns, calamites, small ferns, gymnospermous trees, seed ferns, herbaceous lycopods, and others from unknown origin.

The pattern of spore distribution in the columns did not appear to be affected by the presence of several partings, a feature which calls into question several mechanisms proposed for the origin of partings and also creates difficulties for an autochthonous origin for …


Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba Apr 1981

Storm-Sewer Input Of Heavy Metals Into An Urban Lake Environment, George A. Duba

Dissertations

The purpose of this study was to measure the concentration of lead, cadmium, zinc and copper in runoff entering an urban lake ecosystem and to measure the distribution of these metals in selected tropic levels of the lake.

Fisk Lake was chosen as the study site and is located in East Grand Rapids, Michigan. Samples were collected of stormwater, rainwater and lakewater together with substrate, aquatic macrophytes Peltandra virginica, chironomid larvae, Chironomidae, snails Physa, and eight species of fish, Ictalurus nebulosus, Esox lucius, Lepomis gibbosus, L. macrochirus, Pomoxis nigromaculatus, Micropterus salmoides, Catostomus commersoni, and Perca flavescens. All samples were collected …


Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton Apr 1981

Growth And Recruitment Of Two Penaeids In The Bay Of St. Louis, Mississippi During 1979, Teresa C. Heaton

OES Theses and Dissertations

Juvenile brown (Penaeus aztecus, Ives) and white (Penaeus setiferus, Linnaeus) shrimp were collected from two stations of a nursery area in St. Louis Bay Mississippi, during May to October, 1979. Periods of shrimp recruitment and growth were determined to discern whether the concurrent environmental variables of salinity and temperature had an influence on shrimp abundance and yield. Growth estimates were obtained from length frequency measurements of trawl samples taken over a 24-h period per month from each station. An analysis of variance of length versus the variables of sex, month, station, time of day, salinity and …


Continuous Flow Nutrient Bioassays With Natural Phytoplankton Populations Collected In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers Mar 1981

Continuous Flow Nutrient Bioassays With Natural Phytoplankton Populations Collected In Hillsborough Bay, Florida, City Of Tampa Department Of Sanitary Sewers

Reports

The enclosure system chosen for these experiments was continuous and similar to one described by Jones, Tett, Wallis, and Wood (1978a sn b). They successfully maintained for 41 days in the laboratory, with reasonable constant diversity, a natural phytoplankton community from a Scottish Sea-loch.


Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers Mar 1981

Final Report Of The Hillsborough Bay Water Quality Monitoring Program, City Of Tampa Department Of Sanitary Sewers

Reports

The report presented here is the final communication of data collected during the first year and a half of plant operation at variance standards. In addition, earlier data collected by the City of Tampa are also presented in this report in order to give background information of conditions existing prior to operation under the variance (Appendix C). The earlier data may also describe long term trends and normal seasonal cycles occurring in the bay.


Determination Of Diffusion Coefficients Of Ions In Gels, Kelly A. Sanderson Mar 1981

Determination Of Diffusion Coefficients Of Ions In Gels, Kelly A. Sanderson

Theses & Honors Papers

No abstract provided.