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Measuring Microparticle Adhesion Via High-Speed Rotor, Jacob C. Fearnley Aug 2023

Measuring Microparticle Adhesion Via High-Speed Rotor, Jacob C. Fearnley

Theses and Dissertations

Much is known about the atomic/molecular theories that govern adhesion as well as the macroscopic aspects and properties of adhesion. However, adhesion in the microparticle regime is poorly characterized. We report on experiments that use centrifugal force to remove polystyrene (PS) particles from the surface of a high-speed titanium rotor operated in vacuum. This unique rotor can apply forces far greater than other centrifugal force methods or related techniques using atomic force spectroscopy. The mode of attachment, whether particles were located on the windward side versus leeward side of the spinning rotor, time spent in vacuum prior to experiments, and …

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Detailed Characterization Of Material Deformation, Alexander J. Farnsworth Aug 2023

Detailed Characterization Of Material Deformation, Alexander J. Farnsworth

Theses and Dissertations

This dissertation presents a comprehensive exploration of material deformation at the atomic level, investigating key findings and contributions through three fundamental methods: Sum Frequency Generation Spectroscopy (SFG), X-ray Diffraction (XRD), and Electron Backscatter Diffraction (EBSD). The research commences by uncovering the material dependency of nonresonant responses in both SFG and Second Harmonic Generation (SHG) signals. This redefinition of the nonresonant component as an information-rich carrier, rather than mere background noise, leads to novel insights into the potential applications of SFG. The study then delves further into the influence of mechanical stress on materials, establishing a connection between dislocation density on …

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Front Matter, Vol. 83 No. 2 Aug 2023

Front Matter, Vol. 83 No. 2

Western North American Naturalist

No abstract provided.

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Soil Seed Bank Composition And Spatial Distribution In A Cheatgrass (Bromus Tectorum L.)–Dominated Rangeland In Colorado, Usa, Ryan W. R. Schroeder, Jayne L. Jonas, M. Nikki Grant-Hoffman, Mark W. Paschke Aug 2023

Soil Seed Bank Composition And Spatial Distribution In A Cheatgrass (Bromus Tectorum L.)–Dominated Rangeland In Colorado, Usa, Ryan W. R. Schroeder, Jayne L. Jonas, M. Nikki Grant-Hoffman, Mark W. Paschke

Western North American Naturalist

Invasion by nonnative annual plants that form prolific seed banks, including Bromus tectorum L. (cheatgrass), throughout western North America is a major natural resource concern. Even with known economic and ecological implications, soil seed banks and their potential to impact ecological restoration in arid and semiarid ecosystems are poorly understood. Quantifying the regenerative potential of the soil seed bank—the living seeds in the soil profile and on the soil surface—can help natural resource managers make decisions to increase the likelihood of restoration success. We analyzed the germinable soil seed bank composition and distribution of a rangeland site in western Colorado …

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Effects Of Annual Weather Variation On Peak Herbaceous Yield Date In Sagebrush Steppe, Jonathan Bates, Dustin Johnson, Kirk W. Davies, Tony Svejcar, Stuart Hardegree Aug 2023

Effects Of Annual Weather Variation On Peak Herbaceous Yield Date In Sagebrush Steppe, Jonathan Bates, Dustin Johnson, Kirk W. Davies, Tony Svejcar, Stuart Hardegree

Western North American Naturalist

Interannual climate variability impacts forage yield in semiarid rangelands, but it also affects the timing of peak yields. Knowledge of peak standing crop or yield dates would be useful when planning fieldwork for various research or management activities and for developing more accurate models linking herbage production to climatic variables. In this study, herbaceous yield was measured every 2 weeks (April–August) over an 8-year period in a Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis) community in southeastern Oregon. Date of peak yield (Julian day) was calculated for morphological groups (tall perennial bunchgrasses, perennial forbs, annual forbs), Sandberg bluegrass …

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Interference Between Speaking And Computer Tasks In Younger And Older Adults, Paige Elise Asay Aug 2023

Interference Between Speaking And Computer Tasks In Younger And Older Adults, Paige Elise Asay

Theses and Dissertations

This study examined the effects of computer tasks on speech acoustic measures and the effects of speaking on computer task performance in 30 younger and 30 older adults. Participants completed a speech only task, two computer tasks, and simultaneous speaking and computer tasks. Stimulus sentences included the four corner vowels and two diphthongs embedded between voiceless consonants. Acoustic measures of speech included diphthong transition extent and rate as well as vowel space area (VSA) and vowel articulation index (VAI). A text formatting task included two levels of difficulty. A data entry task included sorting items from a shopping list into …

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Taxonomic Revision And Phylogenetic Analysis Of The Philadelphicus Group In The Genus Proctacanthus (Insecta: Diptera: Asilidae), And Key To All Proctacanthus North Of Mexico, Teagan Marie Mulford Aug 2023

Taxonomic Revision And Phylogenetic Analysis Of The Philadelphicus Group In The Genus Proctacanthus (Insecta: Diptera: Asilidae), And Key To All Proctacanthus North Of Mexico, Teagan Marie Mulford

Theses and Dissertations

Proctacanthus (Macquart 1838), an elegant genus of robber flies within the Asilidae family, plays a significant ecological and economic role. However, the lack of a comprehensive taxonomic treatment hinders their identification and thus their use in evolutionary and behavioral research. This study focuses on the taxonomic revision of the Proctacanthus, identifying the features used in recognizing the philadelphicus Species Group and the rufiventris Species Group. By providing systematic and biological data, describing new species, and offering a key for identification, this research contributes to understanding the ecological significance and geographic distribution and history of Proctacanthus. This work will enhance future …

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Feasibility Of Rna-Based Pathogen Detection In An Infant Formula Matrix, Gweneth Claire Gustafson Aug 2023

Feasibility Of Rna-Based Pathogen Detection In An Infant Formula Matrix, Gweneth Claire Gustafson

Theses and Dissertations

Background: The dairy processing industry is currently hindered by slow, antiquated testing for high-risk pathogens, including Listeria monocytogenes and Cronobacter sakazakii. Powder infant formula's low water activity and substantial fat content enhance the survival and thermotolerance of such foodborne pathogens. As DNA-based detection methods can produce false positives even after cell death, a more accurate approach is needed. The objective of this study is to evaluate the suitability of an RNA-based platform for the detection of pathogens in a dairy powder matrix. Materials and Methods: A unique phenol-chloroform extraction method was used to obtain total RNA from heat-killed and unheated …

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Rural Science Teachers Social Network Analysis Matrices, Rebecca L. Sansom, Tracy Poulsen Aug 2023

Rural Science Teachers Social Network Analysis Matrices, Rebecca L. Sansom, Tracy Poulsen

ScholarsArchive Data

These are the social network matrices for our study of rural science teachers. Each matrix is located on a separate tab on the spreadsheet.

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Critical Engagements With Award Winning Picturebooks: My Journey In Creating A More Equitable Classroom Library, Carrie Elizabeth Crowe Aug 2023

Critical Engagements With Award Winning Picturebooks: My Journey In Creating A More Equitable Classroom Library, Carrie Elizabeth Crowe

Theses and Dissertations

Research consistently shows that students from historically marginalized populations have difficulty accessing texts that represent the realities of their lives. Concerned that such might be the case for my students, I conducted an inventory of my classroom library and sought out award-winning texts that could make my library more diverse and inclusive. I then analyzed these award-winning texts using Bishop's (1992) categories of multicultural literature in order to better understand the picturebooks' underlying messages and ideologies. My examinations showed that the majority of the texts fit into the same category (culturally specific), though I was able to identify award-winning texts …

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Terahertz From Electrons, Electronics From Terahertz, Clayton D. Moss Aug 2023

Terahertz From Electrons, Electronics From Terahertz, Clayton D. Moss

Theses and Dissertations

Time-domain terahertz spectroscopy (THz-TDS) is a valuable technique for studying collective ultrafast phenomena. Several mechanisms exist for converting ultrashort optical laser pulses into coherent THz sources. Broadband THz pulses can be obtained from electron currents in air plasma, which requires combinations of different colors of light to be most effective. I report multi-color generation schemes of THz pulses that deliver coherent THz output. Experimental and theoretical work using the photocurrent model describe ways to use non-harmonic color combinations to utilize several sources of light available in a table-top laser setup. Additionally, THz-TDS is used to study a variety of ultrafast …

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Full Issue Aug 2023

Full Issue

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

No abstract provided.

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Farms Will Publish More Books, Noel B. Reynolds Aug 2023

Farms Will Publish More Books, Noel B. Reynolds

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

This year marks the first time that FARMS has published its own books intended for the general LDS market. The first two were Book of Mormon Authorship Revisited: The Evidence for Ancient Origins and LDS Perspectives on the Dead Sea Scrolls. With this issue of the newsletter we release a third: Ancient Scrolls from the Dead Sea: Photographs and Commentary on a Unique Collection of Scrolls. Before 1997 is over we expect to release three more books (described on page 8).

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Farms Dead Sea Scrolls Database Now Available To Farms Subscribers Aug 2023

Farms Dead Sea Scrolls Database Now Available To Farms Subscribers

Insights: The Newsletter of the Neal A. Maxwell Institute for Religious Scholarship

After several years of research, scanning, text marking, and preparation of photographs, FARMS is pleased to announce that The Dead Sea Scrolls on CD: The FARMS Electronic Database is now available for sale to FARMS subscribers for $249. It is intended primarily for scholars with sufficient skills in biblical Hebrew to do research on the scrolls. Windows 3.1 (or higher) or OS2 is required.

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Exploring The Role Of Salt-Tolerant Halomonas Inoculant In Altering Plant Gene Expression To Improve Salt Tolerance In Alfalfa., Ashley Kay Miller Aug 2023

Exploring The Role Of Salt-Tolerant Halomonas Inoculant In Altering Plant Gene Expression To Improve Salt Tolerance In Alfalfa., Ashley Kay Miller

Theses and Dissertations

Soil salinity is an increasing problem facing agriculture in many parts of the world. Climate change and irrigation practices have led to decreased yields of large areas of farmland due to increased salt levels in the soil. Irrigation introduces salts to the soil that with time accumulate and threaten crop yield. In arid climates like Utah, the practice of irrigation is especially threatening to salt-sensitive crops including alfalfa (Medicago sativa). Plants that have tolerance to salt are needed to feed livestock and the world's population. One approach to address this problem is to introduce genes encoding salt tolerance into the …

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Mahu And Native Hawaiian Culture: Experiences Of Non-Heteronormativity, Rachel Beth Chapman Aug 2023

Mahu And Native Hawaiian Culture: Experiences Of Non-Heteronormativity, Rachel Beth Chapman

Theses and Dissertations

There are extensive amounts of psychological research that highlight the needs and experiences of racial ethnic minority populations in general and more specifically minority sexual identities and genders, also referred to as non-heteronormative populations (Alexeyeff & Besnier, 2014). However, there continues to be a lack of representation in the research of Polynesians and an even greater lack of representation of non-heteronormative Polynesians and their experiences (Allen et al., 2011). Māhū, a population of native Hawaiians who identify as non-heteronormative or third gender, are almost completely absent from scholarly work. This study examines the experience of self-identified māhū and how mental …

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Using De Novo Transcriptomes To Decipher The Relationships In Cutthroat Trout Subspecies (Oncorhynchus Clarkii), Andrea Leena Kokkonen Aug 2023

Using De Novo Transcriptomes To Decipher The Relationships In Cutthroat Trout Subspecies (Oncorhynchus Clarkii), Andrea Leena Kokkonen

Theses and Dissertations

Cutthroat trout (Oncorhynchus clarkii) is a salmonid native to Western North America. For almost 200 years, the taxonomy of these species has fluctuated as ichthyologists and fisheries managers alike have tried to understand the diversity seen within these fishes. In the 1950s, Robert Behnke reexamined the cutthroat trout and identified 14 subspecies based on morphological observations, Pleistocene events, and modern geographic ranges. These designations were instrumental in preserving the remaining diversity of cutthroat trout. Over time, molecular techniques (i.e. karyotypes, allozymes, and mtDNA) have largely replicated Behnke's phylogenies. However, these studies have revealed that some of these relationships are consistently …

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Evapotranspiration In Urban And Agricultural Systems With Interacting Irrigation And Nitrogen Fertilizer Treatments, Samantha R. Shumate Aug 2023

Evapotranspiration In Urban And Agricultural Systems With Interacting Irrigation And Nitrogen Fertilizer Treatments, Samantha R. Shumate

Theses and Dissertations

Nitrogen (N) fertilizer and irrigation are important inputs for all managed plant species, especially in arid and semi-arid climates. The interaction between N management and irrigation can lead to more sustainable practices. This is true for both agricultural and urban environments. Precision nutrient management has been widely adopted by producers in recent decades, and water conservation has become an important goal for turfgrass managers. In urban systems, our goal was to evaluate Kentucky bluegrass (Poa pratensis L.) to determine response to three N fertilizer rates and three irrigation rates in all possible combinations. The main and interacting treatment effects were …

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Improving Xrd Analysis With Machine Learning, Rachel E. Drapeau Aug 2023

Improving Xrd Analysis With Machine Learning, Rachel E. Drapeau

Theses and Dissertations

X-ray diffraction analysis (XRD) is an inexpensive method to quantify the relative proportions of mineral phases in a rock or soil sample. However, the analytical software available for XRD requires extensive user input to choose phases to include in the analysis. Consequently, analysis accuracy depends greatly on the experience of the analyst, especially as the number of phases in a sample increases (Raven & Self, 2017; Omotoso, 2006). The purpose of this project is to test whether incorporating machine learning methods into XRD software can improve the accuracy of analyses by assisting in the phase-picking process. In order to provide …

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Understanding Gender Identification Within Individuals With Autism Using The Bem Sex-Role Inventory, Zackery Alan Cusworth Aug 2023

Understanding Gender Identification Within Individuals With Autism Using The Bem Sex-Role Inventory, Zackery Alan Cusworth

Theses and Dissertations

Gender is a socially derived construct that is taught and understood at young ages. However, not every individual has the same social skills to understand these seen and unseen social cues about gender. The Bem Sex-Role Inventory was given to adult individuals with autism in the United States to better understand their masculine, feminine, and androgenous perceptions. These data were then compared to the original Bem Sex-Role Inventory general population study to see if there were any differences. The data show that males with autism had lower masculine scores and higher feminine scores than males in the general population. Females …

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An Assessment Of Cattle Traffic On, And Seed Dispersion Patterns Of, Sclerocactus Wrightiae, David D. Lariviere Aug 2023

An Assessment Of Cattle Traffic On, And Seed Dispersion Patterns Of, Sclerocactus Wrightiae, David D. Lariviere

Theses and Dissertations

Cattle grazing has been a historic use of rangelands in Utah since Pioneer settlement in the mid 1800's. Wright fishhook cactus is a small globose cactus endemic to an area of 280,000 ha in south-central Utah and was listed as endangered in October of 1979, by the U.S. Fish and Wildlife Service (USFWS). By 2010, concerns were expressed that soil compaction in proximity to the cactus posed a threat to this species, though there was no empirical data to support such concern. In order to assess the impact of cattle traffic on Wright fishhook cactus, we used an imprint device …

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Characterization Of Phage-Host Interactions And Its Impact On Tail Fiber Evolution, Jessica Marie Lewis Aug 2023

Characterization Of Phage-Host Interactions And Its Impact On Tail Fiber Evolution, Jessica Marie Lewis

Theses and Dissertations

Beyond the scope of what our unaided eyes can see is a diverse and rich microbial community that greatly impacts each of our lives. Bacteria are microscopic organisms that can grow, develop, divide, and even rapidly evolve to adapt to new changes in their environment. Because of this, bacteria have gained the ability to thrive in extreme biological niches ranging from the high temperature and pressure surrounding hydrothermal vents to the harsh acidic conditions of our stomachs. One adaptation attracting attention, however, is their capability to survive in the presence of common and even last-resort antibiotics. The WHO recently reported …

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Predicting The Best Birds And Bees: Parental-Efficacy As A Mediator Between Parental Factors And Parent-Child Sex Communication, Meg O. Jankovich Aug 2023

Predicting The Best Birds And Bees: Parental-Efficacy As A Mediator Between Parental Factors And Parent-Child Sex Communication, Meg O. Jankovich

Theses and Dissertations

Recent literature on parent-child sex communication (PCSC) has identified optimal sex communication as being not only frequent, but also open in quality, and proactive in timing. However, no studies have sought to understand what motivates parents to participate in this type of optimal parent-child sex communication, nor assessed these relationships longitudinally. Using Self-Determination Theory (SDT) to inform the analysis, this study investigated parent characteristics (parent's sexual self-concept and parenting dimensions) that may longitudinally predict optimal PCSC. This study further examined whether parental sex communication efficacy mediated these relationships. The sample included 607 mother-child dyads, and the father-figure when available (mother-father-child …

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Loading Force In Recreational Runners And Its Effect On Achilles Tendon Biomechanical Properties, Joshua K. Sponbeck Aug 2023

Loading Force In Recreational Runners And Its Effect On Achilles Tendon Biomechanical Properties, Joshua K. Sponbeck

Theses and Dissertations

Background: Achilles tendinopathy is a common debilitating running related injury. Achilles tendon loading force has been hypothesized as a contributor to Achilles tendinopathy. Loading force through the Achilles tendon during running is impacted by many factors such as footwear and foot strike pattern. Achilles tendon biomechanical (Achilles tendon cross-sectional area, thickness, echogenicity, stiffness, and T2*) responses to loading forces are variable and measurable in vivo. These responses impact the physiologic function of the tendon. Aims: 1) To evaluate baseline Achilles tendon biomechanical characteristics associated with a runner's habitual foot strike pattern. 2) To evaluate single running bout Achilles tendon biomechanical …

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A Refuge And A Bridge: Native American Women's Tribal College Experiences, Morgan Duffy Aug 2023

A Refuge And A Bridge: Native American Women's Tribal College Experiences, Morgan Duffy

Theses and Dissertations

This study, which focuses on the experiences of Native women attending a tribal college of the Northern Cheyenne Nation, responds to the call by Baird-Olson and Ward (2000) and Almeida (1997) for research that allows Native women, or the "hidden half," to tell their stories. Scant research has examined the value of tribal schools for Native American women and the experiences they have had in relation to their reservation and college lives. Providing narratives of women's experiences can illuminate how higher education in tribal college settings holds multiple values for Native women students as it acts as a refuge and …

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Barriers And Facilitating Factors Of Sleep Assessment/Screening Among School Psychology Practitioners, Tyler Jjay Landon Storey Aug 2023

Barriers And Facilitating Factors Of Sleep Assessment/Screening Among School Psychology Practitioners, Tyler Jjay Landon Storey

Theses and Dissertations

Sleep is an important and necessary part of life. While the biological need for sleep among school-aged individuals has not changed over the years, the quality and quantity of their sleep has. School-aged children reporting sleep deficits in the United States is on the rise and a significant body of research establishes associations between a lack of sleep and lower cognition as well as psychological and behavioral problems. These associations can heavily influence the academic progress and success of students. School psychologists are in a unique position to identify and provide support to individuals with sleep issues. Unfortunately, there is …

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The Generalizability Of Proposed Theoretical Factor Models For Common Assessments For Specific Learning Disability In Reading Using A Community Sample, Sean B. Vanhille Aug 2023

The Generalizability Of Proposed Theoretical Factor Models For Common Assessments For Specific Learning Disability In Reading Using A Community Sample, Sean B. Vanhille

Theses and Dissertations

Specific learning disabilities (SLD) are among the most diagnosed developmental disorders in children, with specific learning disability in reading (SLDR) as the most common. SLDR typically occurs due to deficits in phonological processing that can negatively impact decoding and/or reading comprehension skills. Reading deficits are often diagnosed using formal assessments such as the Comprehensive Test of Phonological Processing (CTOPP-2), the Gray Oral Reading Test (GORT-5), the Wechsler Intelligence Scale for Children (WISC-V), and the Woodcock Johnson Achievement Battery (WJ-IV-A). I did not find any research in which the theoretical factor models proposed in the technical manuals of these assessments were …

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A Step Into Structural Biology: Structural Determination Of Tnk1-Uba And Computational Design Of A Radical Sam Cyclase, Yi-Jie Tseng Aug 2023

A Step Into Structural Biology: Structural Determination Of Tnk1-Uba And Computational Design Of A Radical Sam Cyclase, Yi-Jie Tseng

Theses and Dissertations

Structural biology uncovers life's secrets by studying protein structures via techniques like X-ray crystallography. This knowledge drives advancements in protein engineering for the improvement of human lives. Yet, obtaining high-quality crystals in X-ray crystallography is challenging. To overcome this, we used Translocation ETS Leukemia protein Sterile Alpha Motif domain (TELSAM), a promising polymer-forming crystallization chaperone (PFCC), to enhance protein crystallization. Human thirty-eight-negative kinase-1 (TNK1), a key player in cancer progression, possess a ubiquitin association (UBA) domain that binds polyubiquitin and regulates TNK1 activity and stability. Although sequence analysis hints at an unconventional TNK1 UBA domain architecture, its molecular structure lacks …

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Aquatic Insect Communities Remain Impaired Following Large-Scale River Restoration, Jared Meek, Jackson Birrell, Teagan Mulford, Dennis K. Shiozawa, C. Riley Nelson Aug 2023

Aquatic Insect Communities Remain Impaired Following Large-Scale River Restoration, Jared Meek, Jackson Birrell, Teagan Mulford, Dennis K. Shiozawa, C. Riley Nelson

Western North American Naturalist

River manipulation and degradation can cause detrimental impacts on aquatic insect communities. River restoration projects seek to mitigate these human disturbances. Assessing the efficacy of river restoration remains an important goal for river managers and conservation biologists so that improved restoration methods can be used in the future. From 1999 to 2008, the Utah Reclamation Mitigation and Conservation Commission restored a 15-km channelized portion of the Provo River (Wasatch County, Utah, USA). Before (1999) and during (2002) the restoration project, macroinvertebrate samples were collected using modified kick nets from 3 sites within the restored area and 1 site outside the …

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Helpful Or Harmful? The Effect Of Heritage Language Use On Perceived Maternal Closeness In United States Immigrant Families, Catalina Valdez Aug 2023

Helpful Or Harmful? The Effect Of Heritage Language Use On Perceived Maternal Closeness In United States Immigrant Families, Catalina Valdez

Theses and Dissertations

Language use patterns and parent-child relationship quality in immigrant families are both subject to change over time, and past research on the impact of immigrant children's heritage language use on various measures of well-being yields mixed results. Extending scholarship on heritage language use and immigrant family dynamics, I examine the association between different language patterns in U.S. immigrant families and mother's reports of parent-child closeness. I analyze data from 1,142 mothers when their children are in kindergarten, third grade, and fifth grade using the Early Childhood Longitudinal Study "“ Kindergarten Cohort of 2010-2011. I find little variation in perceived maternal …

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