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The Interface Of Breastfeeding And Work: A Phenomenological Exploration Of The Experiences Of White Low-Income Women, Jessica A. Kerby

Dissertations

Vocational psychologists have been called to expand the traditional discourses related to work and career to address the actual work experiences of individuals, especially those of the working class. Breastfeeding rates are on the rise among employed women and mothers of low-income, but little is known about women of low income who seek to concurrently work and breastfeed. Work-family interface theories suggest employed mothers of low-income may experience conflict and/or enhancement through multiple roles. The purpose of this research was to answer the call to vocational psychologists, give voice to the narratives around breastfeeding and work among lowincome mothers, and …

Design Standards Within Constructed Wetlands For The Reduction Of Mosquito Populations In Clark County, Nevada, Phillip C. Bondurant

UNLV Theses, Dissertations, Professional Papers, and Capstones

Wetlands are considered one of the most productive ecosystems in the world and provide many benefits to the environment. However, the slow moving and sometimes stagnant water created by the vegetation in the wetland creates an ideal environment for the proliferation of mosquitoes. Mosquitoes are the most important insect disease vector worldwide. The presence of mosquitoes within wetlands increases the risk of disease transmission among workers and visitors creating a public health concern. Effective design standards aimed at reducing mosquito breeding habitat should be implemented during the construction and planning phase of wetland development to effectively reduce the mosquito populations. …

Protocol Variation Analysis Of Whole Brain Ct Perfusion In Acute Ischemic Stroke, Peter T. Heiberger

UNLV Theses, Dissertations, Professional Papers, and Capstones

Computed tomography perfusion (CTP) analysis is a rapidly advancing imaging modality that is improving diagnosis of brain abnormalities in patients suffering from hemorrhagic or ischemic stroke, traumatic brain injury, vascular occlusion and numerous other conditions. Through the advancements of computed tomography (CT) imaging, including the introduction of the 320-detector row CT with a 16 centimeter range in the z-axis enabling whole brain CTP, perfusion analysis now has a significantly increased clinical utility that is useful for both diagnosis and treatment of central nervous system (CNS) conditions. This study focuses on the procedural and analytical approach to the diagnostic evaluation of …

The Role Of Creativity In Naturalistic Decision-Making Environments: A Systems Approach, Richard Hendrik Feenstra

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this study was to examine the role of creativity in
problem solving situations. Previous research suggested that both
background knowledge and the inability to transfer knowledge across
contexts are important factors in how a problem is ultimately resolved.
Given these findings, the researcher undertook a study on the role
creativity might play when individuals lacking sufficient background
knowledge are faced with a novel real world problem. A question raised
by the researcher whether an absence of background knowledge might
encourage novices to be more creative than their more experienced
counterparts in novel problem solving situations.

Findings of …

Gesture As An Act Of Meaning-Making: An Eco-Social Perspective Of A Sheltered-English Second Grade Classroom, Alessandro A. Rosborough

UNLV Theses, Dissertations, Professional Papers, and Capstones

The purpose of this sociocultural study was to investigate gesture as a mediational tool for meaning-making in learning and teaching a second language. Gesture was observed between a teacher and her immigrant students in a second grade elementary classroom designed specifically for second language learners of English. This study provides an innovative investigation in the role gesture plays as a meditational tool for meaning-making by using a SCT framework at an elementary context level.

Using sociocultural theory, particularly the Vygotskian tradition, this study views gesture as a part of image in thinking. This SCT framework views second language learning in …

Vertical Transmission Of West Nile Virus In Culex Spp. Mosquitoes Of Clark County, Nevada, Vivek K. Raman

UNLV Theses, Dissertations, Professional Papers, and Capstones

West Nile Virus (WNV) is an RNA arbovirus that cycles between mosquitoes and birds, but also infects and causes disease in humans, horses and other vertebrate species. Although most infections are asymptomatic, WNV has emerged as the most common cause of epidemic meningoencephalitis in North America and the leading cause of arboviral encephalitis in the United States.

Mosquitoes of the genus Culex are the most active vectors of WNV in North America. Approximately 85% of human WNV infections in the United States occur in late summer with a peak number of cases in August and September. Vertical transmission is defined …

Historical Biogeography Of Velvet Ants (Hymenoptera: Mutillidae) In The North American Deserts And Arid Lands, Joseph S. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For centuries, scientists have been intrigued by the high amount of biodiversity that is found in the deserts of North America. Recently, several studies have investigated the causes of the high diversity found in desert-dwelling mammals, reptiles, and amphibians. These studies have found that many of these organisms seem to have diversified in response to the same historical events. Little work has been done, however, on diverse desert-dwelling insect groups. In this dissertation, I investigate the patterns of genetic diversity in four groups of nocturnal wasps called velvet ants. I compare the patterns of genetic diversity to the historical events …

Spatial Light Dilution As A Technique For Conversion Of Solar Energy To Algal Biomass, Daniel J. Dye

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A photobioreactor has been designed and developed to efficiently utilize solar irradiance through spatial dilution of sunlight. The concept of spatial light dilution is simple: incident sunlight is spread over a large surface area, thus reducing the photon flux density of the light. The implementation of this technique, however, is difficult. The reactor described within uses a new approach to spatial light dilution, utilizing recently-developed optical components to diffuse concentrated sunlight inside an algae culture. Preliminary productivity tests indicate a 2-3 fold increase in productivity per unit aperture (sunlight collection area) over a control reactor with direct-sunlight. Aperture productivity of …

Kinetic, Mechanistic, And Structural Investigation Of Features Controlling Stereoselectivity Of (R)- And (S)-Hydroxypropyl Com Dehydrogenases From Xanthobacter Autrophicus Strain Py2, Dariusz Adam Sliwa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Enantiopure alcohols are valuable intermediates in fine organic synthesis, in particular for preparation of biologically active compounds. The necessity of preparing single enantiomer drugs in an optically pure form has triggered much research, especially in the pharmaceutical industry. The biocatalytical production of chiral alcohols by alcohol dehydrogenase enzymes is characterized by the asymmetric reduction of the corresponding ketones, usually with high degree of stereoselectivity. The commercial value of the enzymes as stereoselective biocatalysts has been a significant driving force in understanding features that control their mechanism of catalysis and stereoselectivity. This work focuses on two enantiocomplementary dehydrogenase enzymes ((R …

Clarifying The Relationship Between Emotion Regulation, Gender, And Depression, Emi Sumida

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study investigates the relation between emotion regulation problems and clinical depression. One goal of the present study was to bring increased clarity and parsimony to how emotion regulation is presently measured by consolidating three widely used instruments. In addition, of interest was an investigation of whether particular emotion regulation problems and management strategies interact with gender to predict either severity of overall depression symptoms or the presence of a formal mood disorder diagnosis. The results clearly showed that irrespective of a person's gender, particular emotion regulation indicators, both singly, and in combination, are, indeed, more strongly related to the …

The State Of Integrated Open Space Planning: Toward Landscape Integrity?, Lindsay Ex

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Open space planning has been present within the United States for over a century. Traditionally, open space planning efforts tend to focus more exclusively on either socially-based (e.g., recreational, scenic, or park planning) or ecologically-based (e.g., preserves, habitat networks or more general conservation planning) planning efforts. This separation of ecological and social frameworks in open space planning is reinforced by a persistent cultural model, where community and conservation are seen as opposing forces instead of partners.

While recent open space planning efforts have begun to integrate social and ecological frameworks into one plan, the majority of our knowledge on integrated …

Bosom Buddies: Factors Associated With Experiences Of Passionate Friendship Among Men And Women, Katherine A. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Scholars historically have separated friendships and romantic relationships into two qualitatively distinct relationship categories. Contemporary research examining passionate friendships, however, has identified qualities within platonic relationships that appear to mimic characteristics typically associated with romantic relationships. Primary critiques of the existing passionate friendship literature include exclusively examining females, including samples that predominately identified as lesbian, bisexual or questioning, and research utilizing solely qualitative designs.

The current study used a quantitative design to investigate 375 emerging adults' (18-26 years of age; 149 males, 226 females) friendship experiences. Specifically, four quasi-independent variables (i.e., biological sex, sexual orientation, gender-role orientation, and cross vs. …

Assessing Linkages Among Landscape Characteristics, Stream Habitat, And Macroinvertebrate Communities In The Idaho Batholith Ecoregion, Andrew C. Hill

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Understanding the composition of lotic communities and the landscape processes and habitat characteristics that shape them is one of the main challenges confronting stream ecologists. In order to better understand the linkages among landscape processes, stream habitat, and biological communities and to understand how accurately our measurements represent important factors influencing biological communities, it is important to test explicit hypotheses regarding these linkages. Increasing our understanding of aquatic communities in a hierarchical context and recognizing how well our measurements represent factors structuring aquatic communities will help managers better evaluate the influence of land management practices on aquatic ecosystems, direct conservation …

Integration Of Ultrasonic Consolidation And Direct-Write To Fabricate An Embedded Electrical System Within A Metallic Enclosure, Ludwing A. Hernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A research project was undertaken to integrate Ultrasonic Consolitation (UC) and Direct-Write (DW) technologies into a single apparatus to fabricate embedded electrical systems within an ultrasonically consolidated metallic enclosure. Process and design guidelines were developed after performing fundamental research on the operational capabilities of the implemented system. In order to develop such guidelines, numerous tests were performed on both UC and DW. The results from those tests, as well as the design and process guidelines for the fabrication of an embedded touch switch, can be used as a base for future research and experimentation on the UC-DW apparatus. The successful …

Finances In Strong African American Marriages, Bonnie Lichfield Anderson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study focused on how African American couples in happy marriages talked about finances in their couple relationships. Qualitative methodology was used for this study, and the data came from transcribed interviews with participants. Thirty-seven couples who identified their marriages as being strong, happy, or highly satisfying, volunteered to be interviewed for this study. All individual participants (74 total) talked about finances in their marriages, and all interviews were used for the purpose of this study. Their descriptions were coded and analyzed to explore the way that they talked about money issues in their marriages. The research questions focused on …

Environmental And Developmental Indicators In Early Childhood: Relations To Second-Grade Reading Comprehension, Gina A. Cook

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reading success has been linked to high school completion, future job success, and future generations of children who can read. Unfortunately, children who are unable to read on grade level by the end of first grade are at a great disadvantage and unlikely to catch up later. Without the ability to read and comprehend text, all aspects of schooling become progressively more difficult and the challenge of poor reading ability can be so difficult to overcome that many poor readers will not complete high school. For these reasons, it is important to identify early experiences in a child's family environment …

Native Bunchgrass And Invasive Weed Establishment In Low Nutrient Rangeland Soils With Nitrogen And Phosphorus Manipulation, Jeffrey S. Burnham

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competition between native perennial grasses and Bromus tectorum has been studied for many years. Recently, soil nutrients have been immobilized in an effort to preferentially inhibit growth of B. tectorum relative to native species. Most of this work has focused on soil N, but interactions with soil P are less studied and may be important as well. Additionally, although competitive effects and nutrient responses of several Centaurea spp. are well documented, data are lacking on the competitive effects that Centaurea virgata exerts on the establishment of native and exotic communities. A field experiment and a greenhouse experiment were conducted to …

Worry And Rumination: Measurement Invariance Across Gender, Janet A. Carter

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present study examined the factor structure of the Penn State Worry Questionnaire (PSWQ), the Student Worry Questionnaire-30 (SWQ-30), the Anxious Thoughts Inventory (AnTI), the Ruminative Responses Scale (RRS), and the Rumination-Reflection Questionnaire (RRQ). The present study also examined the measurement invariance between men (n = 186) and women (n = 316) in a university sample. Different models for each measure were identified through a review of the literature, and the models were examined through confirmatory factor analyses. The best-fitting models for each measure were retained for subsequent model modification to improve fit and for invariance testing across …

Architecture, Modeling, And Analysis Of A Plasma Impedance Probe, Magathi Jayaram

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Variations in ionospheric plasma density can cause large amplitude and phase changes in the radio waves passing through this region. Ionospheric weather can have detrimental effects on several communication systems, including radars, navigation systems such as the Global Positioning Sytem (GPS), and high-frequency communications. As a result, creating models of the ionospheric density is of paramount interest to scientists working in the field of satellite communication.

Numerous empirical and theoretical models have been developed to study the upper atmosphere climatology and weather. Multiple measurements of plasma density over a region are of marked importance while creating these models. The lack …

Phenotypic And Genetic Characterization Of Wildland Collections Of Western And Searls Prairie Clovers For Rangeland Revegetation In The Western Usa, Kishor Bhattarai

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Western prairie clover [Dalea ornata (Douglas ex Hook.) Eaton & J. Wright] is a perennial legume that occurs in the northern Great Basin, Snake River Basin, and southern Columbia Plateau, whereas Searls prairie clover [Dalea searlsiae (A. Gray) Barneby], also a perennial legume, occurs in the southern Great Basin and surrounding areas. Understanding the genetic and ecotypic variation of these prairie clovers is a prerequisite for developing populations suitable for rangeland revegetation in the western USA. DNA sequences of internal transcribed spacer (ITS/5.8S) and trnK/matK were used to study the phylogeny of these species. The species were distinguished …

An Evolutionary Approach To Optimization Of Compound Stock Trading Indicators Used To Confirm Buy Signals, Allan W. Teeples

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis examines the application of genetic algorithms to the optimization of a composite set of technical indicator filters to confirm or reject buy signals in stock trading, based on probabilistic values derived from historical data. The simplicity of the design, which gives each filter within the composite filter the ability to act independently of the other filters, is outlined, and the cumulative indirect effect each filter has on all the others is discussed. This system is contrasted with the complexity of systems from previous research that attempt to merge several indicator filters together by giving each one a weight …

The Effects Of Pedagogical Agents On Listening Anxiety And Listening Comprehension In An English As A Foreign Language Context, Young-Ah Ko

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study aimed to explore the impact of pedagogical agents in computer-based listening instruction on EFL students' listening anxiety levels and listening comprehension skills. A total of 66 Korean college students received computer-based listening instruction. Students were randomly assigned to one of three conditions: American agent condition, Korean agent condition, or no-agent condition. Additional data sources were included in the experimental design in order to investigate students' learning experience more thoroughly.

Results indicated that there were no statistical differences in listening anxiety levels and listening comprehension skills between students who worked with the agent and students who worked without the …

Fat Taste Transduction In Mouse Taste Cells: The Role Of Transient Receptor Potential Channel Type M5, Pin Liu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A number of studies have demonstrated the ability of free fatty acids to activate taste cells and elicit behavioral responses consistent with there being a taste of fat. Here I show for the first time that long chain unsaturated free fatty acid, linoleic acid, depolarizes taste cells and elicits a robust intracellular calcium rise via the activation of transient receptor potential channel type M5. The linoleic acid-induced responses depend on G protein-phospholipase C pathway indicative of the involvement of G protein-coupled receptors in the transduction of fatty acids. Mice lacking transient receptor potential channel type M5 exhibit no preference for …

Incorporating Spatial Information Into Gas Plume Detection In Hyperspectral Imagery, Cameron S. Grant

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Detection of chemical plumes in hyperspectral data is a problem having solutions that focus on spectral information. These solutions neglect the presence of the spatial information in the scene. The spatial information is exploited in this work by assignment of prior probabilities to neighborhood configurations of signal presence or absence. These probabilities are leveraged in a total probability approach to testing for signal presence in a pixel of interest. The two new algorithms developed are named spatial information detection enhancement (SIDE) and bolt-on SIDE (B-SIDE). The results are explored in comparison to the clutter matched filter (CMF), a standard spectral …

Dietary Milk Fat Globule Membrane Reduces The Incidence Of Aberrant Crypt Foci In Fischer-344 Rats And Provides Protections Against Gastrointestinal Stress In Mice Treated With Lipopolysaccharide, Dallin R. Snow

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Milk fat globule membrane surrounds the fat droplets of milk. It is a biopolymer containing primarily membrane glycoproteins and polar lipids which contribute to its properties as a possible neutraceutical. The aims of the studies were to determine if dietary milk fat globule membrane: (1) confers protection against colon carcinogenesis; and (2) promotes gut mucosal integrity while decreasing inflammation compared to diets containing corn oil or anhydrous milk fat.

Aim 1. Three dietary treatments differing only in the fat source were formulated: (1) AIN-76A, corn oil; (2) AIN-76A, anhydrous milk fat; and (3) AIN-76A, 50% milk fat globule membrane, 50% …

An Investigation Of The Utilization Of Soil Water And Nitrogen Among Diverse Forage Plant Species And Mixtures, Sallee Reynolds

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Species diversity achieved by adding novel functional groups (warm-season grasses and non-leguminous forbs) to pasture land, along with traditional grasses and legumes, could aid in the capture of nutrients and water in pasture systems by offering complementary rooting architecture to aid in water and nitrogen uptake and decrease nitrogen leaching. Because these species may differ from commonly used grasses and legumes in their seasonal pattern of productivity, they could also extend or enhance growing-season productivity. The goal of this project is to better understand the role of plant diversity in 1) nitrogen use and 2) distribution of rooting dynamics and …

Residential Landscape Water Check Programs: Exploring A Conservation Tool, Diana T. Glenn

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In response to drought and regional growth in the arid western United States, urban water demand management is increasingly important. Single family residences use approximately 60% of their water consumption to irrigate landscapes often in excess of plant water requirements. This study utilized a quasi-experimental design to investigate outdoor water consumption and assess the effectiveness of a landscape water check conservation program. Study objectives included describing a contextualized landscape system to reveal variables influencing water use, identifying better ways to evaluate landscape water use, and more effectively targeting and delivering water conservation programs.

The study was conducted during the 2004 …

Establishment And Aesthetic Value Of Native Grass, Legume, And Forb Species For Grassland Restoration In The Northern Intermountain West, Bridget M. Atkin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Interest in the restoration of landscapes native to the Intermountain West is growing as the value of these arid ecosystems is increasingly recognized. Many landscapes within the Intermountain region have been impacted by grazing, development, recreation, and other human-caused disturbances. The complex relationships within the native plant communities of these arid landscapes need to be well-understood biologically, while considering their aesthetic contribution, if restoration efforts are to succeed. Although the use of ecologically appropriate native species is increasing in popularity, there is discontinuity between aesthetics and meaningful ecological contributions. A series of studies was designed to aid in the restoration …

Pervasive Thermal Consequences Of Stream-Lake Interactions In Small Rocky Mountain Watersheds, Usa, Jessica D. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Limnologists and stream ecologists acknowledge the fundamental importance of temperature for regulating many ecological, biological, chemical, and physical processes. I investigated how water temperatures were affected by hydrologic linkages between streams and lakes at various positions along surface water networks throughout several headwater basins in the Sawtooth and White Cloud Mountains of Idaho (USA). Temperatures of streams and lakes were measured for up to 27 months in seven 6 – 41 km² watersheds, with a range of lake influence. When they were ice-free, warming in lakes resulted in dramatically warmer temperatures at lake outflows compared to inflow streams (midsummer …

Ecology And Management Of A High Elevation Southern Range Greater Sage-Grouse Population: Vegetation Manipulation, Early Chick Survival, And Hunter Motivations, Michael R. Guttery

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

My research provided new information concerning the management, ecology, and conservation of greater sage-grouse (Centrocercus urophasianus). I report the results of an experiment using strategic intensive sheep grazing to enhance the quality of greater sage-grouse brood-rearing habitat. Although forb cover, an important component of brood-rearing habitat, responded positively to the grazing treatment, the response of other habitat variables was suppressed because the plots were not protected from domestic and wild herbivores during the years following the treatments. Measurements taken in grazing exclosures confirmed that herbivory by both large and small animals had significant impacts on vegetation. However, despite …