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Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert Jul 2004

Automatic Detection And Validity Of The Sea-Ice Edge: An Application Of Enhanced-Resolution Quikscat/Seawinds Data, David G. Long, Jorg Haarpaintner, Rasmus T. Tonboe, Michael L. Van Woert

Faculty Publications

Sea-ice edge detection is an essential task at the different national ice services to secure navigation in ice-covered seas. Comparison between the Remund and Long ice mask image from enhanced-resolution QuikScat/SeaWinds (QS) products and the analyzed ice edge from high-resolution RADARSAT synthetic aperture radar has shown that the automatically determined QS ice mask underestimates the Arctic ice extent. QS data was statistically analyzed by colocating the data with ice charts around Greenland and with the National Aeronautics and Space Administration Team's Special Sensor Microwave/Imager (SSM/I) ice concentration algorithm over the whole Arctic region. All variables, i.e., the backscatter in vertical …


Treatment Of Hypertriglyceridemia With Omega-3 Fatty Acids: A Systematic Review, Amanda Gloria Lewis Jun 2004

Treatment Of Hypertriglyceridemia With Omega-3 Fatty Acids: A Systematic Review, Amanda Gloria Lewis

Theses and Dissertations

Purpose: To 1) critically appraise available randomized controlled trials (RTCs) addressing the efficacy of long-chain ω-3 fatty acids as a secondary prevention agent of hypertriglyceridemia, and 2) make recommendations for clinical practice.

Data Sources: All RCTs identified from several databases from 1993-2003 were reviewed by two independent reviewers who extracted data from each study and used the previously tested Boyack and Lookinland Methodological Quality Index (MQI) to determine study quality.

Results: Ten studies reported long-chain ω-3 fatty acids to be effective in the treatment of hypertriglyceridemia. The average decrease in triglycerides (TG) was 29%, total cholesterol (TC) 11.6%, very low …


Pressurized Hot Water And Dtpa-Sorbitol, Viable Alternatives For Soil Boron Extraction, Amanda Kathryn Shiffler Jun 2004

Pressurized Hot Water And Dtpa-Sorbitol, Viable Alternatives For Soil Boron Extraction, Amanda Kathryn Shiffler

Theses and Dissertations

Pressurized hot water and DTPA-Sorbitol are two relatively new soil boron (B) extraction methods with potential to replace the cumbersome hot water extraction. The objective of this research is to produce data in support of acceptance or rejection of these two alternative B extractions. The three soil tests were used to extract B from samples of calcareous sand and silt loam and limed, loamy fine sand treated with 10 levels of B and incubated for 7 and 28 d. As B application increased so did extractable B with each extraction method. High correlations (r of 0.977 to 0.999) were observed …


Mechanism Governing The Cellular Susceptibility To Secretory Phospholipase A2, Lauren Blackburn Jensen Jun 2004

Mechanism Governing The Cellular Susceptibility To Secretory Phospholipase A2, Lauren Blackburn Jensen

Theses and Dissertations

Secretory phospholipase A2 (sPLA2) is an important part of apoptosis and disposal of damaged and dying cells. However, healthy cells are not susceptible to attack by sPLA2. Recent studies have focused on membrane properties necessary to induce susceptibility in both artificial and biological membranes. Hydrolysis of phospholipids by sPLA2 requires at least two preliminary steps: first, adsorption of the enzyme to the cellular membrane, and second, movement of a phospholipid into the active site of the enzyme. We determined the effects of susceptibility on each of the two steps and determined the contributions changing the equilibrium constants have on susceptibility. …


Outdoor Education And Meaningful Learning: Finding The Attributes Of Meaningful Learning Experiences In An Outdoor Education Program, Stacy Tooru Taniguchi Jun 2004

Outdoor Education And Meaningful Learning: Finding The Attributes Of Meaningful Learning Experiences In An Outdoor Education Program, Stacy Tooru Taniguchi

Theses and Dissertations

This phenomenological study sought to identify the common attributes of meaningful learning experiences as found in an outdoor education program. The pragmatic educational philosophy of John Dewey provides the rationale for the essence of meaningful learning in our schools and this research identifies the attributes of educative reflective experiences that are also meaningful learning experiences. Thirteen students enrolled in the Wilderness Writing Program, offered during the fall semester of 2003 at Brigham Young University in Provo, Utah, made up the focus group of this study. Their participation in four outdoor recreational activities and their reflections about their experiences became the …


Environmental Protection And Microenterprise Development In The Developing World: A Model Based On The Latin American Experience, Mark D. Wenner, Norman Wright, Abhishek Lal Jun 2004

Environmental Protection And Microenterprise Development In The Developing World: A Model Based On The Latin American Experience, Mark D. Wenner, Norman Wright, Abhishek Lal

Journal of Microfinance / ESR Review

Microenterprises constitute the vast majority of business firms in low- and middle-income developing countries. In Latin America, the sector contributes significantly to employment and gross domestic product. Recently, the expansion of microlending programs has been viewed as an effective means of developing the microenterprise sector and alleviating poverty. However, the nexus between microenterprise development and environmental degradation has remained largely unexplored. It is suspected that the pervasive informality of the microenterprise sector, its sheer size, and the high incidence of poverty in the sector contribute to cumulative environmental degradation and low standards of occupational safety. This paper highlights commonly observed …


Limited Geography And The Book Of Mormon: Historical Antecedents And Early Interpretations, Matthew Roper Jun 2004

Limited Geography And The Book Of Mormon: Historical Antecedents And Early Interpretations, Matthew Roper

Review of Books on the Book of Mormon 1989–2011

No abstract provided.


The Impact Of Species Concept On Biodiversity Studies, Keith A. Crandall, Paul-Michael Agapow, Olaf R. P. Bininda-Emonds, John L. Gittleman, Georgina M. Mace, Jonathon C. Marshall, Andy Purvis Jun 2004

The Impact Of Species Concept On Biodiversity Studies, Keith A. Crandall, Paul-Michael Agapow, Olaf R. P. Bininda-Emonds, John L. Gittleman, Georgina M. Mace, Jonathon C. Marshall, Andy Purvis

Faculty Publications

Species are defined using a variety of different operational techniques. While discussion of the various methodologies has previously been restricted mostly to taxonomists, the demarcation of species is also crucial for conservation biology. Unfortunately, different methods of diagnosing species can arrive at different entities. Most prominently, it is widely thought that use of a phylogenetic species concept may lead to recognition of a far greater number of much less inclusive units. As a result, studies of the same group of organisms can produce not only different species identities but also different species range and number of individuals. To assess the …


Velocity And Temperature Characterization Of The First Vacuum Stage Expansion In An Inductively Coupled Plasma - Mass Spectrometer, William Neil Radicic May 2004

Velocity And Temperature Characterization Of The First Vacuum Stage Expansion In An Inductively Coupled Plasma - Mass Spectrometer, William Neil Radicic

Theses and Dissertations

The inductively coupled plasma - mass spectrometer (ICP-MS) is the analytical instrument of choice for trace element detection and quantification. Despite the popularity of ICP-MS, significant degradation in sensitivity and precision occurs as the result of matrix and instrument-induced effects. The sources of these effects are not well understood, characterized, or correlated to particular plasma operating condition settings or matrix compositions and involve both neutral and charged species. The purpose of this study is to characterize the behavior of metastable Ar (I) atom and Ca (II) ion through the measurement of Doppler velocities and fluorescence line width "temperatures."

For the …


N9 Alkylation And Glycosylation Of Purines; A Practical Synthesis Of 2-Chloro-2'-Deoxyadenosine, Minghong Zhong May 2004

N9 Alkylation And Glycosylation Of Purines; A Practical Synthesis Of 2-Chloro-2'-Deoxyadenosine, Minghong Zhong

Theses and Dissertations

(a) The Robins reagent [2-acetamido-6-O-(diphenylcarbamoyl)purine] was utilized for glycosylation under Lewis acid conditions. Regioselectivity of glycosylation depends on the glycosyl donor and its 2-O- or 2-N-protecting group. Regioselective N9 glycosylation of 2-acetamido-6-O-(diphenylcarbamoyl)purine with problematic glucosamine has been accomplished by protecting the amino function as a phthalimido group with consequent stabilization of the oxocarbenium cation, and lowering the activation energy by introduction of trichloroacetimidate at the anomeric carbon.

(b) 6-Heteroaryl functions [6-(1,2,4-triazol-4-yl) and 6-(imidazol-1-yl)] were introduced into purine derivatives for regioselective N9 alkylation. The regiospecificity of alkylation mainly results from steric effects due to the coplanar conformation of the two linked …


The "Fair" Triathlon: Equating Standard Deviations Using Non-Linear Bayesian Models, Steven Mckay Curtis May 2004

The "Fair" Triathlon: Equating Standard Deviations Using Non-Linear Bayesian Models, Steven Mckay Curtis

Theses and Dissertations

The Ironman triathlon was created in 1978 by combining events with the longest distances for races then contested in Hawaii in swimming, cycling, and running. The Half Ironman triathlon was formed using half the distances of each of the events in the Ironman. The Olympic distance triathlon was created by combining events with the longest distances for races sanctioned by the major federations for swimming, cycling, and running. The relative importance of each event in overall race outcome was not given consideration when determining the distances of each of the races in modern triathlons. Thus, there is a general belief …


Margaret Cavendish And Scientific Discourse In Seventeenth-Century England, Alisa Curtis Bolander May 2004

Margaret Cavendish And Scientific Discourse In Seventeenth-Century England, Alisa Curtis Bolander

Theses and Dissertations

Although the natural philosophy of Margaret Cavendish is eclectic and uncustomary, it offers an important critique of contemporary scientific methods, especially mechanism and experimentalism. As presented in Observations upon Experimental Philosophy and Blazing World, Cavendish's natural philosophy incorporates rationalistic and subjective elements, urging contemporary natural philosophers to recognize that pure objectivity is unattainable through any method of inquiry and that reason is essential in making sense and use of scientific observation.

In addition to its scientific implications, Cavendish's three-tiered model of matter presents interesting sociopolitical associations. Through her own use of metaphor and her theoretical fusion of matter and motion, …


Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes Apr 2004

Identification Of An Il-17-Producing Nk1.1neg Inkt Cell Population Involved In Airway Neutrophilia, Paul B. Savage, Marie-Laure Michel, Alexandre Castro Keller, Christophe Paget, Masakazu Fujio, Francois Trottein, Chi-Huey Wong, Elke Schneider, Michael Dy, Maria C. Leite-De-Moraes

Faculty Publications

Invariant natural killer T (iNKT) cells are an important source of both T helper type 1 (Th1) and Th2 cytokines, through which they can exert beneficial, as well as deleterious, effects in a variety of inflammatory diseases. This functional heterogeneity raises the question of how far phenotypically distinct subpopulations are responsible for such contrasting activities. In this study, we identify a particular set of iNKT cells that lack the NK1.1 marker (NK1.1neg) and secrete high amounts of interleukin (IL)-17 and low levels of interferon (IFN)-{gamma} and IL-4. NK1.1neg iNKT cells produce IL-17 upon synthetic ({alpha}-galactosylceramide [{alpha}-GalCer] or PBS-57), as well …


Effect Of Cryptobiotic Crust Type On Microarthropod Assemblages In Piñon-Juniper Woodland In Central New Mexico, S. L. Brantley, U. L. Shepherd Apr 2004

Effect Of Cryptobiotic Crust Type On Microarthropod Assemblages In Piñon-Juniper Woodland In Central New Mexico, S. L. Brantley, U. L. Shepherd

Western North American Naturalist

Cryptobiotic crusts make up an important part of the ground cover in arid systems. Along with their roles of retarding soil erosion and enhancing soil fertility, crusts may also be supporting local and regional arthropod biodiversity. We inventoried arthropod species in mossy, lichen, and mixed (lichen and mossy) cryptobiotic crusts at 2 sites in central New Mexico piñon-juniper habitat. We collected 240 crust samples and used a heptane flotation technique to extract the microarthropods. We found 39 species of microarthropods and small macroarthropods, with significantly fewer species on lichen. Species richness was higher in March than in August, but diversity …


Selection Of Ants By The American Black Bear (Ursus Americanus), Janene Auger, Gary L. Ogborn, Clyde L. Pritchett, Hal L. Black Apr 2004

Selection Of Ants By The American Black Bear (Ursus Americanus), Janene Auger, Gary L. Ogborn, Clyde L. Pritchett, Hal L. Black

Western North American Naturalist

We examined selection of ants as food by black bears (Ursus americanus) in Utah by comparing the genera of ants we sampled from study plots in 5 vegetation types with those found in bear scats. In the plots we found 641 ant colonies representing 18 genera. Five genera comprised 85% of all colonies sampled: Formica, Lasius, Camponotus, Tapinoma, and Myrmica. Thirteen genera were found in scats, but 99% were composed of the same 5 listed above. Limited utilization of some ant genera by black bears may reflect body size, colony size, nest type, and presence or absence …


Comparative Life History For Populations Of The Sceloporus Grammicus Complex (Squamata: Phrynosomatidae), Aurelio Ramírez-Bautista, Elsa Jiménez-Cruz, Jonathon C. Marshall Apr 2004

Comparative Life History For Populations Of The Sceloporus Grammicus Complex (Squamata: Phrynosomatidae), Aurelio Ramírez-Bautista, Elsa Jiménez-Cruz, Jonathon C. Marshall

Western North American Naturalist

A Teotihuacán population of the Sceloporus grammicus complex was compared with other previously studied populations (Parque Nacional Zoquiapan [PNZ], Monte Alegre Ajusco [MAA], Pedregal San Angel [PSA], Cantimplora [CA], Capulín, Laguna, Paredon, Michilia, and south Texas) for variations in several life history characteristics (SVL at sexual maturity, reproductive period, ovulation and gestation time, and litter size). Mean body size at sexual maturity of females from Teotihuacán was larger than PNZ, MAA, CA, and Capulín. Reproductive period (vitellogenesis, ovulation, gestation, and birth) for the Teotihuacán population was the shortest of all populations. In the Teotihuacán population, gestation time was similar to …


Influence Of Black-Tailed Prairie Dog Towns (Cynomys Ludovicianus) On Carnivore Distributions In The Oklahoma Pandhandle, Michael J. Shaughnessy Jr., Richard L. Cifelli Apr 2004

Influence Of Black-Tailed Prairie Dog Towns (Cynomys Ludovicianus) On Carnivore Distributions In The Oklahoma Pandhandle, Michael J. Shaughnessy Jr., Richard L. Cifelli

Western North American Naturalist

Carnivores were recorded at prairie dog towns and non-prairie dog town paired sites in the Oklahoma Panhandle over 4 sampling sessions from October 1995 to February 1997. We established carnivore presence through the use of baited tracking plates dusted with chalk and matched with infrared-triggered cameras. Five carnivore species were recorded at both prairie dog towns and paired sites across the Oklahoma Panhandle. Of these, 4 were recorded with sufficient regularity to permit analyses. Carnivores were analyzed at prairie dog towns across the entire Panhandle and in the Panhandle's westernmost county (Cimarron County) only. Canids showed no significant preference for …


Influence Of Yellow Starthistle (Centaurea Solstitialis) On Small Mammals In Central California, Kirsten Christopherson, Michael L. Morrison Apr 2004

Influence Of Yellow Starthistle (Centaurea Solstitialis) On Small Mammals In Central California, Kirsten Christopherson, Michael L. Morrison

Western North American Naturalist

Yellow starthistle (Centaurea solstitialis) is native to Europe and Asia and has quickly invaded disturbed grasslands and rangelands in the western United States. The purpose of our study was to determine the effects of starthistle on rodents at Beale Air Force Base, Yuba County, California, by examining rodent species diversity, species abundance, age structure, and reproductive condition among locations with low, medium, and high percent cover and height of starthistle. Listed in decreasing order of abundance, the rodents were house mouse (Mus musculus), California vole (Microtus californicus), deer mouse (Peromyscus maniculatus), western …


Plant Species Diversity In A Grassland Plant Community: Evidence For Forbs As A Critical Management Consideration, Monica L. Pokorny, Roger L. Sheley, Tony J. Svejcar, Richard E. Engel Apr 2004

Plant Species Diversity In A Grassland Plant Community: Evidence For Forbs As A Critical Management Consideration, Monica L. Pokorny, Roger L. Sheley, Tony J. Svejcar, Richard E. Engel

Western North American Naturalist

This study quantified species and functional group diversity in a grassland plant community in southwestern Montana. Specific objectives were to measure the richness and density of functional groups within the grassland community, measure the biomass of each functional group, and calculate diversity indices for each functional group. We hypothesized that diversity would be greater than previous descriptions for the Festuca idahoensis/Agropyron spicatum habitat type because our multiple-season method would recognize seasonal and environmental variations in community composition. Of the species present, we hypothesized that forb functional groups account for the majority of richness and biomass of this grassland plant community. …


Feeding Behavior And Performance Of A Rabbitbrush Leaf-Beetle (Trirhabda Lewisii) Feeding On Chrysothamnus Nauseosus Regrowth After Fire, Ann L. Herzig, Cynthia Skema Apr 2004

Feeding Behavior And Performance Of A Rabbitbrush Leaf-Beetle (Trirhabda Lewisii) Feeding On Chrysothamnus Nauseosus Regrowth After Fire, Ann L. Herzig, Cynthia Skema

Western North American Naturalist

Fire often positively affects the growth and nutrient content of plants regrowing after a burn. These changes have been associated with preferential feeding by herbivores in burned areas. In this study in southeastern Wyoming, Chrysothamnus nauseosus Pursh (rubber rabbitbrush) regrowing after a fire produced new shoots with a distinct growth form. Shoots were longer than those on unburned control sites and had longer leaves with longer internodes between leaves. We conducted feeding trials to detect whether C. nauseosus shoots regrowing after fire were nutritionally superior to shoots from unburned plants for the specialist leaf beetle, Trirhabda lewisii Crotch (Coleoptera: Chrysomelidae). …


Habitat Use By Brush Mice (Peromyscus Boylii) In Southeastern Arizona, Amy B. Gottesman, Michael L. Morrison, Paul R. Krausman Apr 2004

Habitat Use By Brush Mice (Peromyscus Boylii) In Southeastern Arizona, Amy B. Gottesman, Michael L. Morrison, Paul R. Krausman

Western North American Naturalist

No abstract provided.


Are Desert Basins Effective Barriers To Movements Of Relocated Black Bears (Ursus Americanus)?, Jon P. Beckmann, Carl W. Lackey Apr 2004

Are Desert Basins Effective Barriers To Movements Of Relocated Black Bears (Ursus Americanus)?, Jon P. Beckmann, Carl W. Lackey

Western North American Naturalist

No abstract provided.


Importance Of Outcrossing For Fruit Production In Slickspot Peppergrass, Lepidium Papilliferum L. (Brassicaceae), Ian Robertson Apr 2004

Importance Of Outcrossing For Fruit Production In Slickspot Peppergrass, Lepidium Papilliferum L. (Brassicaceae), Ian Robertson

Western North American Naturalist

No abstract provided.


For The Birds: Book Reviews Of A Trio Of Guides And An Encyclopedia, Clayton M. White Apr 2004

For The Birds: Book Reviews Of A Trio Of Guides And An Encyclopedia, Clayton M. White

Western North American Naturalist

No abstract provided.


Full Issue, Vol. 64 No. 2 Apr 2004

Full Issue, Vol. 64 No. 2

Western North American Naturalist

No abstract provided.


Reproductive Activity And Distrubution Of Bats In Nebraska, Russell A. Benedict Apr 2004

Reproductive Activity And Distrubution Of Bats In Nebraska, Russell A. Benedict

Western North American Naturalist

New geographic, reproductive, and seasonal records are presented for 11 of 13 bats inhabiting Nebraska. New geographic records are presented for 10 species, most notably Myotis lucifugus (120 miles west of nearest known record), M. septentrionalis (42 miles west of nearest record), Nycticeius humeralis (72 miles west of nearest record), and Pipistrellus subflavus (258 miles northwest of nearest record). New reproductive localities are recorded for 9 species, particularly the 1st records of breeding by Pipistrellus subflavus in Nebraska (Cherry and Dixon Counties) and the 2nd record of breeding by Lasionycteris noctivagans in Nebraska (Lancaster County). New records of timing of …


Temperature And High Salinity Effects In Germinating Dimorphic Seeds Of Atriplex Rosea, M. Ajmal Khan, Bilquees Gul, Darrell J. Weber Apr 2004

Temperature And High Salinity Effects In Germinating Dimorphic Seeds Of Atriplex Rosea, M. Ajmal Khan, Bilquees Gul, Darrell J. Weber

Western North American Naturalist

Atriplex rosea L. (Chenopodiaceae; tumbling orach), an annual herb, is a widely established weedy species of disturbed sites in all counties of Utah. Seeds of Atriplex rosea were collected from a salt marsh in Faust, Utah, and are dimorphic, light brown, and 2–2.5 mm wide, or black and 1–2 mm wide. Seed germination responses of the black and brown seeds were studied over a range of salinity and temperature. Both brown and black seeds germinated at 1000 mM NaCl, and the optimal temperature for germination of both types was 20–30 °C. Variation in temperature, however, affected germination of black seeds …


Molecular-Dynamics Simulation Of The Effect Of Ions On A Liquid–Liquid Interface For A Partially Miscible Mixture, Richard L. Rowley, Kent E. Wardle, Eric Carlson, Douglas Henderson Apr 2004

Molecular-Dynamics Simulation Of The Effect Of Ions On A Liquid–Liquid Interface For A Partially Miscible Mixture, Richard L. Rowley, Kent E. Wardle, Eric Carlson, Douglas Henderson

Faculty Publications

Molecular-dynamics simulations were performed to model the effect of added salt ions on the liquid-liquid interface in a partially miscible system. Simulations of the interface between saturated phases of a model 1-hexanol + water system show a bilayer structure of 1-hexanol molecules at the interface with OH heads of the first layer directed into the water phase and the opposite orientation for the second layer. The alignment of the polar OH groups at the interface stabilizes a charge separation of sodium and chloride ions when salt is introduced into the aqueous phase, producing an electrical double layer. Chloride ions aggregate …


Fluorescence Detectors For Proteins And Toxic Heavy Metals, Uchenna Prince Paul Apr 2004

Fluorescence Detectors For Proteins And Toxic Heavy Metals, Uchenna Prince Paul

Theses and Dissertations

An inexpensive detector for proteins is described. The detection technique was based on two-photon excitation intrinsic protein fluorescence using a visible 532 nm diode-pumped nano laser as the excitation source. Proteins that exhibit intrinsic fluorescence must contain at least one tryptophan, tyrosine, or phenylalanine residue in their amino acid sequences. The detector was characterized and was found to have a detection limit of 4 micro-molar for tryptophan, 22 micro-molar for tyrosine and 500 micro-molar for phenylalanine. Bovine serum albumin, a serum protein with 3 tryptophan residues in its amino acid sequence was also used to characterize the detector. It was …


Analysis Of Clinically Important Compounds Using Electrophoretic Separation Techniques Coupled To Time-Of-Flight Mass Spectrometry, Zlatuse Durda Peterson Apr 2004

Analysis Of Clinically Important Compounds Using Electrophoretic Separation Techniques Coupled To Time-Of-Flight Mass Spectrometry, Zlatuse Durda Peterson

Theses and Dissertations

Capillary electrophoretic (CE) separations were successfully coupled to time-of-flight mass spectrometric (TOFMS) detection for the analysis of three families of biological compounds that act as mediators and/or indicators of disease, namely, catecholamines (dopamine, epinephrine, norepinephrine) and their O-methoxylated metabolites (3-methoxytyramine, norepinephrine, and normetanephrine), indolamines (serotonin, tryptophan, and 5-hydroxytryptophan), and angiotensin peptides. While electrophoretic separation techniques provided high separation efficiency, mass spectrometric detection afforded specificity unsurpassed by other types of detectors.

Both catecholamines and indolamines are present in body fluids at concentrations that make it possible for them to be determined by capillary zone electrophoresis coupled to TOFMS without employing any …