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Articles 91261 - 91290 of 713701

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Determination Of Fatty Acid Concentrations In Various Strains Of Freshwater Green Picoplankton Algae (Class Eustigmatophyceae), P. Ashcraft, R. Jacks, B. Martinez, J. Rodriguez, A.B. Burns, A. Gurnsey, L. Taylor, A. Teague, J. Totty, V.L. Fox, A. Williams Jan 2023

Determination Of Fatty Acid Concentrations In Various Strains Of Freshwater Green Picoplankton Algae (Class Eustigmatophyceae), P. Ashcraft, R. Jacks, B. Martinez, J. Rodriguez, A.B. Burns, A. Gurnsey, L. Taylor, A. Teague, J. Totty, V.L. Fox, A. Williams

Journal of the Arkansas Academy of Science

Algae are of scientific and commercial interest due to their ease of culture and high fatty acid content. The extracted fatty acids from these phytoplankton may potentially be used as an additional test for phylogenetic classification of new algal strains (Tonon et al. 2002), as well as in a supplement for human consumption and producing next-generation biofuels. Of interest is the fatty acid content contained within various algal isolates within the class Eustigmatophyceae. Algal strains were collected and isolated from locations in Lake Chicot in Arkansas, Tower Pond and Lake Itasca at Itasca State Park in Minnesota, and Thayer Lake …

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Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors Jan 2023

Journal Of The Arkansas Academy Of Science Volume 77, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Determining Mating Type And Species Of A Natural Isolate Of Dictyostelium Using Molecular Techniques And Sexual Crosses, S.N. Baviskar, C. Catron, H. Jenkins, M. Smith Jan 2023

Determining Mating Type And Species Of A Natural Isolate Of Dictyostelium Using Molecular Techniques And Sexual Crosses, S.N. Baviskar, C. Catron, H. Jenkins, M. Smith

Journal of the Arkansas Academy of Science

Cellular slime molds, Dictyostelium, are bactivorous, soil-dwelling amoebae. When food is available, cells reproduce asexually by binary fission. Under certain environmental conditions, such as darkness and humidity, Dictyostelium reproduces sexually. The sexual cycle is uniquely social and has unusual features. First, sexual reproduction in most eukaryotes usually involves fusion of two gametes. But, in Dictyostelium, triparental inheritance is observed (Bloomfield et al. 2019), in which gamete fusion involves more than two gametes. Second, most eukaryotic species have two sexes or mating types, but Dictyostelium species are known to have more than two mating types. Even though Dictyostelium species show variations …

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Noteworthy Parasites (Trematoda, Cestoda, Phthiraptera) Of Three Birds (Aves: Passeriformes; Pelecaniformes; Piciformes) From Arkansas, C.T. Mcallister, H.W. Robison Jan 2023

Noteworthy Parasites (Trematoda, Cestoda, Phthiraptera) Of Three Birds (Aves: Passeriformes; Pelecaniformes; Piciformes) From Arkansas, C.T. Mcallister, H.W. Robison

Journal of the Arkansas Academy of Science

Between November 2020 and March 2021, three species of birds, one each of a tufted titmouse (Baeolophus bicolor), pileated woodpecker (Dryocopus pileatus), and great blue heron (Ardea herodias) were salvaged from Lawrence and Polk counties, Arkansas, and examined for parasites. Found were four taxa of parasites, including a dicrocoeliid trematode, a cyclophyllidean cestode, and species of philopterid and menoponid lice. We document new host and distributional records for these parasites from select birds of the state.

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Spermiogenesis In The Western Siren, Siren Nettingi (Caudata: Sirenidae), S.E. Trauth Jan 2023

Spermiogenesis In The Western Siren, Siren Nettingi (Caudata: Sirenidae), S.E. Trauth

Journal of the Arkansas Academy of Science

I investigated spermiogenesis in the Western Siren, Siren nettingi (formerly Western Lesser Siren, Siren intermedia nettingi) from salamanders collected periodically over a span of 21 yr (1994–2015) in northeastern Arkansas. My primary objective in this study is to present histologically and ultrastructurally, for the first time, the novel sequence of spermatological events of the spermiogenic process in this species. I describe the transformational stages from secondary spermatocytes to mature biflagellated spermatozoa, all of which occur within the lumen of testicular lobules. These new-to-science processes begin with nuclear displacement and expansion within spermatids, which occur after their detachment from Sertoli cells …

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Histomorphology Of The Distal Urogenital Ducts In The Male Northern Crawfish Frog, Rana Areolata Circulosa (Anura: Ranidae), S.E. Trauth, R.G. Neal Jan 2023

Histomorphology Of The Distal Urogenital Ducts In The Male Northern Crawfish Frog, Rana Areolata Circulosa (Anura: Ranidae), S.E. Trauth, R.G. Neal

Journal of the Arkansas Academy of Science

We examined the microanatomy of the distal urogenital ducts in the male Northern Crawfish Frog (Rana areolata circulosa) from a small sample (n = 5) collected in February and March from central Arkansas over a 5-year period (2017–2022). Specifically, we sought information on the following structures: (1) the paired Wolffian (urogenital) ducts caudally from the kidneys to their merging with the urodeum of the cloaca, (2) the paired seminal vesicles (sperm storage structures), and (3) the paired Müllerian ducts and glands. This study provides new information on these urogenital ducts and promotes a clearer understanding of this anatomical region for …

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No Sperm Morphometric Differences Between Two Snapping Turtle Species, J.D. Konvalina, S.E. Trauth Jan 2023

No Sperm Morphometric Differences Between Two Snapping Turtle Species, J.D. Konvalina, S.E. Trauth

Journal of the Arkansas Academy of Science

We examined sperm morphometrics between Chelydra serpentina and Macrochelys temminckii. When both species are combined, we found significant correlations between total sperm length and sperm head length as well as sperm tail length and sperm head length. In addition, we observed significant correlations between total sperm length and sperm tail length. T-tests revealed no significant differences in any of the sperm morphometrics between the two species. Both snapping turtle species had greater values for every sperm morphometric when compared to another freshwater turtle. The strong correlation between total sperm length and sperm tail length is concurrent with what has previously …

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Keynote Address And Meeting Program, Academy Editors Jan 2023

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Instructions To Authors, Academy Editors Jan 2023

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

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Development Of Holographic Optical Elements For Use In Wound Monitoring, Pamela Stoeva, Tatsiana Mikulchyk, Brian Rogers, M. Oubaha, Suzanne Martin, Dervil Cody, M.A. Ferrara, G. Coppola, Izabela Naydenova Jan 2023

Development Of Holographic Optical Elements For Use In Wound Monitoring, Pamela Stoeva, Tatsiana Mikulchyk, Brian Rogers, M. Oubaha, Suzanne Martin, Dervil Cody, M.A. Ferrara, G. Coppola, Izabela Naydenova

Conference Papers

Wounds that fail to heal impact the quality of life of 2.5 % of the total population. The costs of chronic wound care will reach $15–22 billion by 2024. These alarming statistics reveal the financial strain for both the medical industry and society. A solution can be found in compact and accessible sensors that offer real-time analysis of the wound site, facilitating continuous monitoring and immediate treatment, if required. Benefits of these sensors include reduction of cost and can extend the reach of healthcare to remote areas. The progression of a wound site can be closely monitored with holographic optical …

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Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Ananthkumar Jayamani Jan 2023

Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Ananthkumar Jayamani

Mechanical and Aerospace Engineering Dissertations - Archive

Ground test facilities are an imperative part of the design and development of flying vehicles. In the case of high-enthalpy facilities, evaluating the gasdynamic and thermochemical state of the test gas poses challenges due to high temperature effects. This study aims to contribute to the development impulse facilities by developing reduced-order models resolving the flowfields of such facilities. Developed as a part of this study are various method-of-characteristics (MoC) algorithms which consider gases under varying levels of thermochemical complexity. The algorithms span from simple calorically perfect gases to full thermochemical nonequilibrium. The first set of algorithms was limited to unsteady …

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Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu Jan 2023

Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu

Mechanical and Aerospace Engineering Dissertations - Archive

Carbon fiber-reinforced composites are increasingly used in aerospace application thanks to their excellent specific stiffness and strength. However, incomplete understanding of their failure behaviors leads to composite components often being designed with a high Safety Factor, limiting their advantages. Using computational methods, this project studies carbon fiber-reinforced composite microstructures for the objective of understanding and improving material performances under compression load which is one of the main considerations in primary aerospace structure design. A Finite Element (FE) model for the evaluation of composite compression behaviors was developed, allowing the identification of several key material properties affecting composite performance. The numerical …

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Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti Jan 2023

Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti

Mechanical and Aerospace Engineering Dissertations - Archive

The field of cooperative, multi-vehicle systems has witnessed a significant expansion and evolution, yielding considerable opportunities for improved autonomy, resilience, and robustness. Despite these promising developments, complex challenges persist in ensuring secure and efficient rendezvous among cooperative peers. The term "rendezvous," within the realm of cooperative control, refers to the simultaneous convergence of multi-vehicle systems to a designated target location. In missile guidance, the problem of multiple pursuer missiles achieving rendezvous with a target is termed as a salvo attack. Current methodologies often grapple with issues related to synchronization, high latency and network security, all of which can adversely impact …

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Modeling, Diagnosis And Control Of Complex Nonlinear Uncertain Dynamical Systems: From Algorithm Design To Physical Experiment, Jingting Zhang Jan 2023

Modeling, Diagnosis And Control Of Complex Nonlinear Uncertain Dynamical Systems: From Algorithm Design To Physical Experiment, Jingting Zhang

Open Access Dissertations

Complex systems with uncertain and nonlinear dynamics are a large class of very important systems in modern engineering. Typical examples include automatic robots, aeroengines, chemical processes, manufacturing systems, and power networks. In this dissertation, we focus on the problems of dynamics modeling, tracking control, and fault diagnosis of complex nonlinear uncertain dynamical systems (NUDSs), in terms of both algorithm design and physical experiment. The studied NUDSs include: (i) discrete-time lumped parameter systems that are modeled by discrete difference equations; (ii) continuous-time distributed parameter systems modeled by partial differential equations; and (ii) soft robots with a highly nonlinear and uncertain dynamical …

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A Rigid Body Framework For Modeling And Simulation Of Formation Of Autonomous Agents, Suguru Sato Jan 2023

A Rigid Body Framework For Modeling And Simulation Of Formation Of Autonomous Agents, Suguru Sato

Mechanical and Aerospace Engineering Theses - Archive

Formation motion, wherein multiple agents operate within close proximity while maintaining precise relative positions and coordinated movements has a significant impact in the realm of Uncrewed Aerial Systems (UAS). Formation establishment, and station-keeping have been critical research areas as several missions can be conceived, and accomplished by groups of “simple” autonomous agents. Advances in this research have led to multiple advantages in areas such as reconnaissance, aerospace exploration, map building, search and rescue, etc. particularly, if the formation motion is inspired by nature and natural phenomena such as flock of birds, school of fish, hydrodynamics (smooth streamlines), magnetic fields, and …

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Functional Linear Regression: Linear Hypothesis Testing With Functional Response, Rasha Mohammed A. Alsaeed Jan 2023

Functional Linear Regression: Linear Hypothesis Testing With Functional Response, Rasha Mohammed A. Alsaeed

Mathematics Dissertations - Archive

Hypothesis testing is a crucial aspect of functional data analysis, allowing re- searchers to make inferential decisions based on samples of functional data. The inherent infinite dimensionality of functional data makes conventional hypothesis testing methods, such as Hotelling’s T2, difficult to apply due to the singularity of the sample covariance matrix. To address this issue, a common practice is to project functional data into a lower-dimensional space before conducting hypoth- esis tests. However, the choice of projection space can impact the validity and power of the tests, as the projected hypothesis problem may not be equivalent to the original problem. …

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Examining Patent Eligibility, Charles Duan Jan 2023

Examining Patent Eligibility, Charles Duan

Scholarly Articles in Law Reviews & Journals

A firestorm of debate has surrounded the Supreme Court of the United States’s 2014 decision Alice Corp. Pty. Ltd. v. CLS Bank International on the doctrine of patentable subject matter eligibility under 35 U.S.C. § 101. As the Court’s leading articulation of doctrine, which generally excludes from patenting abstract ideas, laws of nature, and natural phenomena, Alice has been criticized as unpredictably vague and overly constrictive of patentability, with the effect of “decimating” patents, innovation, technological investment, and even the United States’ competitiveness against other nations. To support these criticisms and calls for reform, scholars and practitioners have frequently turned …

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Vicarious Trauma And Elementary School Counselors, Erin M. Duduit Jan 2023

Vicarious Trauma And Elementary School Counselors, Erin M. Duduit

Walden Dissertations and Doctoral Studies

Vicarious trauma has been a focus of scholars for many years and demonstrates that vicarious trauma effects professional behaviorally, personally, and physiologically. This quantitative cross-sectional study explored the relationship between vicarious trauma and occupational exposure (caseload size) disrupting the cognitive structures of empathy, control, and esteem. The theoretical framework for this study was the constructivist self-development theory, which described how helping professionals develop vicarious trauma after exposure to traumatic stories. The social cognitive theory was also used for this study, explaining how elementary school counselors can increase their capacity for empathizing through modeling and experiencing empathy from others. The study …

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Optical Design Study Of A High-Resolution Spectrograph Utilizing Photonic Lanterns For A Large Fiber Array Telescope, Richard D'Alo Jan 2023

Optical Design Study Of A High-Resolution Spectrograph Utilizing Photonic Lanterns For A Large Fiber Array Telescope, Richard D'Alo

Graduate Thesis and Dissertation 2023-2024

Large area fiber array telescopes are a relatively modern development in the long history of telescope design and effectively create a single large equivalent aperture by combining many smaller unit telescopes at a fraction of the cost. In this study a spectrograph optical design is demonstrated that utilizes photonic lanterns in the input fiber feed for the Large Fiber Array Spectroscopic Telescope (LFAST) design concept, where photonic lanterns provide a simplified approach to the fiber feed originally proposed for LFAST. Conservation of etendue is applied to derive the relationship between slit size and photonic lantern ratio, and classical echelle spectrograph …

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Capacity Building For Organizational Resilience: Integrating Standards On Risk, Disruption And Continuity In The Curriculum, Lisa Greenwood, Dawn Hess, Yewande S. Abraham, Jennifer Schneider Jan 2023

Capacity Building For Organizational Resilience: Integrating Standards On Risk, Disruption And Continuity In The Curriculum, Lisa Greenwood, Dawn Hess, Yewande S. Abraham, Jennifer Schneider

Articles

Disruption is an inevitable factor in business and society, while inability to mitigate and manage risk can cause irreparable damage to business, the economy, and our ways of life. The COVID-19 pandemic has heightened interest in standards-based strategies for risk management and crisis preparedness to enhance organizational and societal resilience. University curricula that integrate national and international standards offer students a rich skill-set for effective performance in their careers. Moving forward, we must cultivate capable professionals who understand the challenges and risks facing society, and who grasp standards and systems for strategic planning, response, and recovery to promote organizational resilience …

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Comparative Analysis Of Fullstack Development Technologies: Frontend, Backend And Database, Qozeem Odeniran Jan 2023

Comparative Analysis Of Fullstack Development Technologies: Frontend, Backend And Database, Qozeem Odeniran

College of Graduate Studies: Theses & Dissertations

Accessing websites with various devices has brought changes in the field of application development. The choice of cross-platform, reusable frameworks is very crucial in this era. This thesis embarks in the evaluation of front-end, back-end, and database technologies to address the status quo. Study-a explores front-end development, focusing on angular.js and react.js. Using these frameworks, comparative web applications were created and evaluated locally. Important insights were obtained through benchmark tests, lighthouse metrics, and architectural evaluations. React.js proves to be a performance leader in spite of the possible influence of a virtual machine, opening the door for additional research. Study b …

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Operating Artificial Intelligence To Assist Physicians Diagnose Medical Images: A Narrative Review, Oluwaseun Adelaja, Hussein Alkattan Jan 2023

Operating Artificial Intelligence To Assist Physicians Diagnose Medical Images: A Narrative Review, Oluwaseun Adelaja, Hussein Alkattan

Mesopotamian Journal of Artificial Intelligence in Healthcare

Medical image diagnostics is crucial to healthcare since it aids in the diagnosis and treatment of a variety of diseases and conditions. However, the process is time-consuming and prone to human error. In recent years, artificial intelligence has been a powerful tool for enhancing medical imaging diagnosis. Using AI algorithms for medical picture interpretation has the potential to revolutionise the field by improving accuracy, efficacy, and standardization. These algorithms can quickly sift through enormous amounts of medical imaging, finding anomalies, quantifying features, and providing useful information to help medical professionals make judgments. AI-based systems can be used to track the …

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Exploring The Top Five Evolving Threats In Cybersecurity: An In-Depth Overview, Maad Mijwil, Omega John Unogwu, Youssef Filali, Indu Bala, Indu Bala Jan 2023

Exploring The Top Five Evolving Threats In Cybersecurity: An In-Depth Overview, Maad Mijwil, Omega John Unogwu, Youssef Filali, Indu Bala, Indu Bala

Mesopotamian Journal of CyberSecurity

The term cybersecurity refers to an environment capable of protecting digital devices, networks and information from unauthorized access and preventing data theft or alteration. It is composed of a collection of carefully crafted techniques, processes, and practices to protect sensitive information and deterring cyber-attacks. In the recent period, the domain of cybersecurity has undergone rapid growth in response to the increasing cyber threats. Cybersecurity includes important tactics that help protect the digital environment, which are firewalls, encryption, secure passwords, and threat detection and response systems. Employees must be trained on these tactics. This article will discuss the five most pressing …

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A Comprehensive Review Of Security Measures In Database Systems: Assessing Authentication, Access Control, And Beyond, Habeeb Omotunde, Maryam Ahmed Jan 2023

A Comprehensive Review Of Security Measures In Database Systems: Assessing Authentication, Access Control, And Beyond, Habeeb Omotunde, Maryam Ahmed

Mesopotamian Journal of CyberSecurity

This paper presents a comprehensive review of security measures in database systems, focusing on authentication, access control, encryption, auditing, intrusion detection, and privacy-enhancing techniques. It aims to provide valuable insights into the latest advancements and best practices in securing databases. The review examines the challenges, vulnerabilities, and mitigation strategies associated with database security. It explores various authentication methods, access control models, encryption techniques, auditing and monitoring approaches, intrusion detection systems, and data leakage prevention mechanisms. The paper also discusses the impact of emerging trends such as cloud computing, big data, and the Internet of Things on database security. By synthesizing …

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The Effect Of Exceptionality Label On School Psychologists During The Evaluation Process, Rachel Jacob Jan 2023

The Effect Of Exceptionality Label On School Psychologists During The Evaluation Process, Rachel Jacob

Theses and Dissertations--Educational, School, and Counseling Psychology

School psychologists often lead the evaluation process that is responsible for identifying students with an education-based disability. They are also responsible for providing recommendations for the student following the evaluation. The current study is focusing on the variable of exceptionality label as it is a universally present variable that has the potential to affect all evaluations. Two recent studies have examined and found labeling bias on preservice educators (Allday et al., 2011; Fisher et al., 2022). This study sought to expand this research by looking at labeling bias in school psychologists. The study measured the effect of exceptionality label on …

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An Examination Of Factors Impacting Home-School Collaboration In Head Start Populations, Madison Mei-Mei Yee Jan 2023

An Examination Of Factors Impacting Home-School Collaboration In Head Start Populations, Madison Mei-Mei Yee

Theses and Dissertations--Educational, School, and Counseling Psychology

Two essential pillars in a preschool-age student’s life include their caregiver and their teacher. In turn, it is unsurprising that a more cohesive relationship between these two figures can promote better wellbeing, academic skills, and overall developmental growth in young children. Unfortunately, a multitude of barriers impede home-school collaboration, such as socioeconomic status, non-English speaking households, and caregiver mental health, just to name a few. Head Start, a federally funded preschool program, targets underserved populations who often relate to these named barriers. Head Start works out of the Parent, Family, and Community Engagement (PFCE) Framework, a framework specifically geared toward …

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Organizational Leadership Culture And Gender Inequality In The C-Suite, Rocelia Hornbuckle Jan 2023

Organizational Leadership Culture And Gender Inequality In The C-Suite, Rocelia Hornbuckle

Walden Dissertations and Doctoral Studies

Women in the automotive industry often struggle to advance into top leadership positions. More specifically, culture and gender inequality affect senior-level and higher women leaders trying to achieve a position in the C-Suite in automotive manufacturing organizations. The purpose of this qualitative phenomenological study was to explore the lived experiences of senior-level and higher women seeking a C-Suite position. The research questions addressed the lived experiences of women who strive to be promoted to C-Suites positions. Three sub-questions were used to evaluate participants' perceptions, leveraging them to increase awareness of the cultural and gender inequality affecting the representation of women …

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Teachers’ Perceptions Of Social Emotional Learning Instruction And High Residential Mobility Students’ Reading Literacy, Janel Dorene Morris Jan 2023

Teachers’ Perceptions Of Social Emotional Learning Instruction And High Residential Mobility Students’ Reading Literacy, Janel Dorene Morris

Walden Dissertations and Doctoral Studies

Based on recommendations from research, leaders in a north Texas public school district implemented social emotional learning (SEL) to address academic gaps among high residential mobility (HRM) students. Incorporating SEL instruction improves academic achievement 11 percentile points on average; however, in Adoniram School District (ASD), 2021 passing rates fell 8% from 2019 despite adopting SEL curriculum. The purpose of this qualitative case study was to explore how ASD elementary teachers instructed SEL, and their perceptions of how SEL techniques influenced HRM elementary students’ reading literacy development. The study on social and emotional skills (SSES) conceptual framework guided this study because …

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Experiences Of African American Students In A Stem-Focused Community Program, Angela Blount Jan 2023

Experiences Of African American Students In A Stem-Focused Community Program, Angela Blount

Walden Dissertations and Doctoral Studies

The United States has invested millions of dollars in STEM program initiatives; however, African Americans in STEM career fields are underrepresented. The purpose of this qualitative hermeneutic phenomenological study aimed to explore the lived experiences of African-American first-year college students from rural communities in a STEM program and whether their experiences influenced their decision to pursue a STEM major in college. Spencer’s phenomenological variant of ecological systems theory (PVEST) was used to frame the study. Data were collected from semistructured interviews with eight African American first-year college students from rural communities. Coding analysis involved identifying meaning units and situated narratives …

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Middle And High School Administrators’ Perceptions Of Retention Factors At Title I Campuses, Creseda Hawk Jan 2023

Middle And High School Administrators’ Perceptions Of Retention Factors At Title I Campuses, Creseda Hawk

Walden Dissertations and Doctoral Studies

AbstractPrincipal turnover has a negative influence on the stability of a school’s culture and climate and on student achievement. Many U.S. principals leave their positions by the end of their 2nd year, and this number is disproportionately higher for low-income school districts. The purpose of this basic qualitative study was to investigate middle and high school principals’ perceptions of factors influencing administrator turnover at Title I schools across a southeastern U.S. state. Herzberg’s two-factor theory of motivation grounded this study. The research questions were focused on principals’ perceptions of motivation and hygiene factors. Semistructured interviews were conducted with 10 purposively …

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