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Bilingual Latinx Adolescents Experiences In A Predominantly White Institution: A Mixed Method Study, Danieli Marie Mercado Ramos Jan 2025

Bilingual Latinx Adolescents Experiences In A Predominantly White Institution: A Mixed Method Study, Danieli Marie Mercado Ramos

Dissertations

Extent scholarship has provided insight into how Latinx adolescents actively experience exclusion. These adolescents are often the targets of microaggressions tied to their language (Gonzalez et al., 2018), ethnicity, race, and intersecting identities--such as being bilingual Latinx students--which serve as reminders that they do not belong. However, little is known about Spanish-English bilingual Latinx adolescents and how their heritage language plays a role in predominantly white spaces and institutions. This convergent parallel mixed methods study explored how Spanish-English bilingual Latinx students in the Midwest described their experiences in a predominantly white institution (PWI). A total of 42 Spanish-English bilingual Latinx …


Evolution Of Bacteria: The Subsequent Relationships Between Different Species And Their Hosts, Helen Appleberry Jan 2025

Evolution Of Bacteria: The Subsequent Relationships Between Different Species And Their Hosts, Helen Appleberry

Dissertations

To explore the relationship between two recently identified bacterial species (S. anginosus and S. urinae), three aims were designed. First, niche ranges were identified via two metagenome databases. Different niche ranges were identified between the two groups. S. urinae was more specific to the urogenital tract. S. anginosus appeared to be present across human anatomical niches. Secondly, specific genes to the S. urinae group were identified. This gives insight into the genomic and phenotypic differences previously identified. Thirdly, a temporal study was created to view S. urinae in female urine over 8 weeks. This showed stability in the urinary microbiome …


Deciphering The Source Of Escherichia Coli In Urinary Tract Infections: A Comparative Metagenomic Analysis Of The Female Urogenital Microbiome, Alexis Annabel Avalos Jan 2025

Deciphering The Source Of Escherichia Coli In Urinary Tract Infections: A Comparative Metagenomic Analysis Of The Female Urogenital Microbiome, Alexis Annabel Avalos

Dissertations

In 2019, there was a 140.19% increase in deaths due to urinary tract infections (UTIs) compared to 1990, worldwide. One of the common uropathogens known to associate with UTIs in females is Escherichia coli. The prevailing belief is that E. coli in the bladder originates in the rectum, passing its way from the perineal, to the vagina, and finally into the bladder. Known as the Fecal-Perineal-Urethral (FPU) hypothesis, this “origin story” has been supported by several studies that have relied on genotyping or serotyping isolates collected from the bladder and rectum. Most notably, culturing isolates from samples has been central …


Selecting For Lysis In A Temperate Phage Population, Haley Atkins Jan 2025

Selecting For Lysis In A Temperate Phage Population, Haley Atkins

Dissertations

The ongoing evolutionary arms race between bacteria and bacteriophages (phages) is a prime example of Red Queen hypothesis, where continuous adaptation drives survival. This study focuses on Escherichia coli-infecting temperate phages, which dominate natural environments and contribute to bacterial resistance mechanisms. Despite their prevalence, temperate phages are less suited for phage therapy due to their lysogenic life cycle, where they integrate into bacterial genomes instead of lysing the host. In contrast, obligately lytic phages, which directly lyse bacterial cells, are ideal for therapeutic use but occur less frequently in nature. This research aims to select for lytic behavior in temperate …


Reconceptualizing Christian Nationalism, Robert Stevenson Jan 2025

Reconceptualizing Christian Nationalism, Robert Stevenson

Dissertations

This thesis sets out to critically engage with existing research on Christian nationalism. It argues that current research suffers from a methodological focus that is too broad, and theoretical grounding that is too imprecise, both of which prevent researchers from grasping the full scope and intent of Christian nationalism, as imagined by Christian nationalists themselves. Drawing on data collected from X accounts (formerly Twitter) of Christian nationalist users, Christian nationalist podcasts, and Christian nationalist books, it employs qualitative content analysis, mapped to Bourdieusian field theory to provide a structured approach for the understanding complex data involving multiple spheres of power, …


Refining Cross-Population Polygenic Risk Scores Across Diverse Populations, Mansi Patel Jan 2025

Refining Cross-Population Polygenic Risk Scores Across Diverse Populations, Mansi Patel

Dissertations

Large biobanks containing whole genome sequences connected to the deidentified electronic health records of hundreds of thousands of individuals are increasingly available to researchers. This has facilitated the development of polygenic risk scores (PRS), which use machine learning to predict risk of disease and other phenotypes from millions of genetic variants. Due to Eurocentricity of available genetic data, PRS have primarily been trained in populations of European descent. Differences in allele frequencies, effect sizes, and linkage disequilibrium patterns between populations can limit the transferability of PRS across different populations. Given that most data are from European genetic ancestry populations, we …


The Impact Of Lactobacillus Supplementation On Gut Microbiome Composition And Phage Induction In Mice, Kimia Boreiri Jan 2025

The Impact Of Lactobacillus Supplementation On Gut Microbiome Composition And Phage Induction In Mice, Kimia Boreiri

Dissertations

The mammalian gastrointestinal (GI) tract harbors a dense and dynamic community of microbes known as the gut microbiota, which plays vital roles in digestion, immunity, and overall health. Among these, probiotic bacteria such as Lactobacillus strains have garnered attention for their ability to influence microbial community structure and host physiology. This study investigated the effects of five Lactobacillus strains, Lactobacillus casei R1A482, Lactobacillus casei O3, Lactobacillus rhamnosus GG, Lactobacillus gasseri ATCC 33323, and Lactobacillus paragasseri UMB1065, on the gut microbiome of Swiss Webster mice over a six-week feeding period. To reduce stress, mice were fed Lactobacillus strains using gelatin pellets …


Decoding The Origins Of Infection: A Machine Learning Framework, Nirupama G. Shanbhag Jan 2025

Decoding The Origins Of Infection: A Machine Learning Framework, Nirupama G. Shanbhag

Dissertations

Many infections can be attributed to a specific microorganism. For example, while there can be many causes of urinary tract infections (UTIs), such as the bacterial species Klebsiella pneumoniae or Enterococcus sp., the most widespread cause for UTIs is uropathogenic Escherichia coli. Generally, diseases or infections that are the result of a single pathogenic organism are more easily understood. Other diseases, such as irritable bowel disease (IBD), cannot be attributed to one member in the community; rather, it is a result of dysbiosis of the microbial community (microbiota) of the gastrointestinal tract, a combination of an overgrowth of problematic members …


Anti-Inflamatory Mechansim Of Bacillus Subtilis Derirved Exopolysaccharide, Adrian Taylor Ibarra Jan 2025

Anti-Inflamatory Mechansim Of Bacillus Subtilis Derirved Exopolysaccharide, Adrian Taylor Ibarra

Dissertations

Exopolysaccharides (EPS) secreted by the commensal bacterium Bacillus subtilis exhibit potent anti-inflammatory properties, yet the underlying molecular mechanisms remain incompletely understood. We hypothesized that EPS reprograms antigen-presenting cells toward a tolerogenic state by modulating TLR4–MyD88 signaling. To test this, we began using a chemically defined, high-yield EPS production and purification protocol that largely eliminates protein and DNA contaminants, thus improving functional reproducibility across experiments using this new method. In vitro, EPS engaged TLR4 on murine dendritic cells (DC2.4) without inducing classical NF-κB activation, seen by LPS stimulation. Rather, EPS treatment upregulated inhibitory molecules, PD-L1 and PD-L2 while leaving activation markers, …


Investigating The Mechanism Of Resistance To Ido1 Enzyme Inhibitor Treatment In Human Glioblastoma, Kyla Shivakumar Hatton Jan 2025

Investigating The Mechanism Of Resistance To Ido1 Enzyme Inhibitor Treatment In Human Glioblastoma, Kyla Shivakumar Hatton

Dissertations

Glioblastoma (GBM) is the most common and most aggressive form of adult cancer in the central nervous system, with GBM accounting for the majority of all malignant brain tumors. GBM is currently considered to be an incurable form of cancer, with over 14,000 patients diagnosed in the United States last year. Given the success of immunotherapy for treating other types of cancer, our group has investigated the possibility of therapeutically neutralizing immunosuppressive indoleamine 2,3 dioxygenase 1 (IDO1) in patients with GBM. Canonically, IDO1 is an immunosuppressive cytoplasmic enzyme that catalyzes the first step in metabolizing L-tryptophan into L-kynurenine (ie. ↓L-Trp→↑L-Kyn). …


Developing Chemically Defined Serum-Free Medium For Leukemic Blast And Stem Cell Expansion, Carmen Eva Finley Jan 2025

Developing Chemically Defined Serum-Free Medium For Leukemic Blast And Stem Cell Expansion, Carmen Eva Finley

Dissertations

The relapse and chemotherapy resistance are the major challenges of acute myeloid leukemia (AML) treatment, driven by a rare population of leukemia stem cells (LSCs). LSCs are unique types of cells which evade standard chemotherapies and can regenerate AML post-treatment. Targeting LSC therapy remains limited, in part due to the lack of reliable in vitro AML culture systems to grow LSCs for drug discovery. This study aimed to engineer a chemically defined, serum-free 2D in vitro culture condition that supports either the expansion of leukemic blasts (LBs) or primary human LSCs by optimizing current protocols for hematopoietic stem cells (HSCs) …


Investigating Whether Txnrd2 Is A Therapeutic Target Against Triple Negative Breast Cancer Using African American-Derived Models, Keacha Chang Jan 2025

Investigating Whether Txnrd2 Is A Therapeutic Target Against Triple Negative Breast Cancer Using African American-Derived Models, Keacha Chang

Dissertations

Despite similar breast cancer incidence rates, African American (AA) women experience a 40% higher mortality rate compared to Caucasian American (CA) women. This disparity is multifactorial and particularly pronounced in the Chicago area. AA women are twice as likely to be diagnosed with triple-negative breast cancer (TNBC), often at a younger age and with more aggressive disease. TNBC is a heterogeneous subtype lacking targeted therapies and is associated with the poorest prognosis among breast cancer types. Therefore, there is an urgent need for novel therapeutic strategies for TNBC, especially those tailored to AA patients. The thioredoxin pathway is essential for …


Capturing Diverse Adolescents’ Social Contexts: The Development Of An Ethnic-Racial Microaffirmations Scale For Peer Interactions, Maria Radulescu Jan 2025

Capturing Diverse Adolescents’ Social Contexts: The Development Of An Ethnic-Racial Microaffirmations Scale For Peer Interactions, Maria Radulescu

Dissertations

The development of a strong and positive sense of ethnic-racial identity (ERI) has been identified as an asset for ethnically and racially marginalized adolescents. Peer interactions during the adolescent years can support ERI development. In particular, a subtle micro-level form of peer support—microaffirmations—may be protective for ERI processes. However, the field of microaffirmations is very small, and there is no scale that captures adolescents’ experiences of ethnic-racial microaffirmations from their peers. The current study developed an ethnic-racial peer microaffirmations scale based on extant literature and feedback from 4 focus groups with 22 sophomore high school students. Findings indicated that 5 …


The Bacterial Sensing Nuclear-Oligomerization Domain 2 Receptor In The Brain: Location And Potential Function, Julia Smyth Jan 2025

The Bacterial Sensing Nuclear-Oligomerization Domain 2 Receptor In The Brain: Location And Potential Function, Julia Smyth

Dissertations

Nucleotide-binding oligomerization domain-2 (NOD2) is a cytosolic receptor, activated by bacterial peptides that initiates innate immune responses through nuclear factor-κB (NF-κB), mitogen-activated protein kinase (MAPK), and Caspase-1 pathways. While the role of NOD2 in inflammation outside the central nervous system (CNS) is well-established, especially in the gastrointestinal system, its expression and function in the brain remain poorly defined. Previous genetic studies suggest a link between NOD2 and neurological and psychiatric conditions, including stroke, Parkinson’s disease, and schizophrenia. However, information regarding NOD2 expression, localization, and function in the CNS is limited. In this work, we investigated NOD2 expression, localization, and regulation …


"I'M Not Having Fun Anymore": A Qualitative Analysis Of Gender And Harassment In Bars And Clubs, Phoebe Marie Jackson Jan 2025

"I'M Not Having Fun Anymore": A Qualitative Analysis Of Gender And Harassment In Bars And Clubs, Phoebe Marie Jackson

Dissertations

Sexual harassment, while often spoken about in hushed tones or ignored altogether, happens frequently and often loudly. 66 percent of women who have experienced sexual harassment report that the harassment took place in a public space, such as work, school, or on the street (Kearl, 2018). Harassment is not discreet, but rather normalized, and those who experience it are expected to brush it off or take it in their stride. However, such harassment and subsequent dehumanization has a deteriorating effect on the mental well-being of those affected (Graham et. al., 2016). This study aims to hone in on the effect …


Systematic Review Examining How Black Youth In The United States Cope With Stressful And Traumatic Experiences, Marcus Aaron Flax Jan 2025

Systematic Review Examining How Black Youth In The United States Cope With Stressful And Traumatic Experiences, Marcus Aaron Flax

Dissertations

Coping is an important behavioral skillset that youth use to emotionally regulate after experiencing stress or trauma. Research has repeatedly highlighted the stressors that Black youth experience, often finding that Black youth face higher levels of stress and trauma than their White peers. However, there has been a lack of research in understanding how Black youth cope with these higher levels of stress. This systematic review includes 72 studies (N = 16,205 participants) examining the frequency and effectiveness of coping strategies used by Black youth in response to a trauma or stressor, along with the associations between utilized coping strategies …


Voices Of Chinese American Emerging Adults: Complex Racial Identities, Family Dynamics, And Mental Health Experiences, Maxwell Lou Xu Jan 2025

Voices Of Chinese American Emerging Adults: Complex Racial Identities, Family Dynamics, And Mental Health Experiences, Maxwell Lou Xu

Dissertations

Although Asian Americans are the fastest growing racial minority group in the United States, they remain significantly underrepresented in mental health research. Furthermore, research on Asian American mental health often aggregates the experiences of different Asian ethnic groups, creating a limited understanding of how distinct ethnic groups may differ in their mental health experiences. This interview study with Chinese American emerging adults ages 18–25 from varied family contexts (single-race, multiracial, and adoptive households) examines how members of this population make sense of the relationships between their identity, family, and mental health. This thesis posits that Chinese Americans' nuanced experiences—particularly around …


The Forced Sterilization Of Quechua-Speaking Women In Peru: The Role Of Epistemic Injustice In The Perpetration Of Genocide, Geraldine Diaz Jan 2025

The Forced Sterilization Of Quechua-Speaking Women In Peru: The Role Of Epistemic Injustice In The Perpetration Of Genocide, Geraldine Diaz

Dissertations

The forced sterilization of Quechua-speaking women in Peru from 1996 to 2000 represents a case of genocide in which the state as an epistemic agent has a fundamental role. Although the systematic sterilization was carried out under the guise of a family planning program, the targeting of these women provides strong circumstantial evidence of genocidal intent. According to the testimonies of these women, medical staff, acting on behalf of the government, performed tubal ligation procedures through coercion, threats, lies, bribery, manipulation, and other tactics where the state intentionally withheld information, misinformed women, and failed to obtain proper consent. This research …


Editor's Note, Marites Tiongco Jan 2025

Editor's Note, Marites Tiongco

DLSU Business & Economics Review

No abstract provided.


Alteration Of Fit In Soft Milled Cobalt-Chromium And Zirconia Fixed Dental Prostheses After Ceramic Veneering, Elie Daou Jan 2025

Alteration Of Fit In Soft Milled Cobalt-Chromium And Zirconia Fixed Dental Prostheses After Ceramic Veneering, Elie Daou

Annual Research Symposium

No abstract provided.


Urban Coyotes As A Source Of Conflict With Humans: An Evaluation Of Common Management Practices, Paul D. Curtis, David L. Bergman, Angeline Barker, Daniel Bogan, Mary Ann Bonnell, Pierre Canac-Marquis, David Drake, Dave Kay, Brian F. Wakeling, H. Bryant White Jan 2025

Urban Coyotes As A Source Of Conflict With Humans: An Evaluation Of Common Management Practices, Paul D. Curtis, David L. Bergman, Angeline Barker, Daniel Bogan, Mary Ann Bonnell, Pierre Canac-Marquis, David Drake, Dave Kay, Brian F. Wakeling, H. Bryant White

Human–Wildlife Interactions Monographs

Wildlife often serves as a catalyst for conflict among stakeholders. Management actions that are intended to address sources of disagreement may initiate additional conflict. The Association of Fish and Wildlife Agencies Human–Wildlife Conflict Working Group initiated an effort to identify management actions commonly used to address unwanted coyote (Canis latrans) interactions within urban environments and identify the benefits and challenges associated with each action. Challenges with coyotes in urban environments include aggressive behavior toward humans and pets, attacks, disease exposure, and domestic livestock damage. Although elimination of all attractants would prove preventative in most instances, in practice this …


Cultivating Community-University Partnerships Within The Chicago Region Food System, Hanan Abdillahi, Vivian Cossey, Tania Schusler, Kevin Erickson, Karen Schauwecker, Sarah Ku, Ray Dybzinski Jan 2025

Cultivating Community-University Partnerships Within The Chicago Region Food System, Hanan Abdillahi, Vivian Cossey, Tania Schusler, Kevin Erickson, Karen Schauwecker, Sarah Ku, Ray Dybzinski

School of Environmental Sustainability: Faculty Publications and Other Works

We interviewed 22 organizations in the Chicago Regional Food System to gain insights on their current initiatives, assets, challenges, future visions, and perceived roles of universities in advancing their work. We analyzed themes to report on strong consensus or varied perspectives related to this work. This report aims to advise Loyola’s School of Environmental Sustainability's future work and collaboration activities with Chicago Food System organizations.


The Effect Of Social Hierarchy And Captivity On Behavior In Cercopithecus Petaurista, Haley Bombard Jan 2025

The Effect Of Social Hierarchy And Captivity On Behavior In Cercopithecus Petaurista, Haley Bombard

Undergraduate Scholarship and Creative Works

The social hierarchy within three Cercopithecus petaurista individuals was studied to determine how the influence of captivity affects behavior. The three individuals were monitored from August-November, and the data retained was focused on aggression and allogrooming behaviors. The group consisted of one dominant male and two females in the Central Florida Zoo, and behavioral observations were recorded at 10-minute intervals. Results showed that the dominant male infrequently engaged in allogrooming behavior but more often received it from the less dominant females. The hierarchy and social status of the females was shown and influenced by the allogrooming given and received between …


“A Bond As Strong As A Lock And Chain”: Youth Of Color In Low-Income Communities Use Photovoice To Theorize Developmentally Nurturing Processes Of Their Cross-Age Mentoring Programs, Kevin M. Miller, Katherine Tyson Mccrea, Victor Sarna, William Donnelly, Grace Ann Fitzgibbons, Jamie Kessler, Cynthia Onyeka, Chana Matthews, Maryse Richards, Elijah Daniels, Dreyce Denton Jan 2025

“A Bond As Strong As A Lock And Chain”: Youth Of Color In Low-Income Communities Use Photovoice To Theorize Developmentally Nurturing Processes Of Their Cross-Age Mentoring Programs, Kevin M. Miller, Katherine Tyson Mccrea, Victor Sarna, William Donnelly, Grace Ann Fitzgibbons, Jamie Kessler, Cynthia Onyeka, Chana Matthews, Maryse Richards, Elijah Daniels, Dreyce Denton

Social Work: School of Social Work Faculty Publications and Other Works

Youth of color experiencing low-income in the United States face multiple human rights violations: over-policing, community violence, racial discrimination, and insufficient voice in the programs and policies that impact their current and future lives. To accomplish transitional justice, participatory processes are needed that elicit youths’ cultural strengths and wisdom about themselves, their social conditions, services they find helpful, and why those services are helpful. This study highlights findings from a photovoice that elicited youths’ perspectives about a crossage mentoring out-of-school-program. Responding to “What does mentoring mean to you?” 147 youth took photographs in their communities and wrote narratives about the …


Self-Efficacy Is Not Just About The Self: African American Cross-Age Youth Mentors, Amzie Moore, Maria Wathen, Katherine Tyson Mccrea, Maryse Richards Jan 2025

Self-Efficacy Is Not Just About The Self: African American Cross-Age Youth Mentors, Amzie Moore, Maria Wathen, Katherine Tyson Mccrea, Maryse Richards

Social Work: School of Social Work Faculty Publications and Other Works

Objective: Self-efficacy, a belief in one’s capacity to achieve specific outcomes despite obstacles, is tied to a myriad of positive outcomes in the educational, relational, mental health, and future achievement of Black youth. Black youth living in racially segregated, low-income urban communities face greater obstacles than other youth. This study examines how participation as mentors in a cross-age mentoring program influences self-efficacy, and what social and environmental factors are related to changes in self-efficacy

Method: The study employs growth-curve analyses to investigate the impact of participation on self-efficacy and to examine the effects of the strength of the mentor-mentee relationship, …


Pre-Migration Victimization And Fear Of Violent Crime Among New Arrivals In Chicago / Victimización Y Miedo Al Crimen Violento En El País De Origen De Los Migrantes Recién Llegados A Chicago, Cristian L. Paredes, Keyla Navarrete, Anna E. Bullock, Brianna Hernandez, Raymond A. Akumbilim Jan 2025

Pre-Migration Victimization And Fear Of Violent Crime Among New Arrivals In Chicago / Victimización Y Miedo Al Crimen Violento En El País De Origen De Los Migrantes Recién Llegados A Chicago, Cristian L. Paredes, Keyla Navarrete, Anna E. Bullock, Brianna Hernandez, Raymond A. Akumbilim

Sociology: Faculty Publications and Other Works

This project explores the situations and experiences of new arrivals/asylum seekers who have recently arrived in Chicago. Chicago has experienced a significant increase in the number of newcomers, due to Operation Lone Star, launched by Texas Governor Greg Abbott in March 2021. Since August 2022, Governor Abbott has bused more than 30,000 migrants to Chicago. The City of Chicago has acknowledged its responsibility to welcome everyone regardless of immigration status, adopting a proactive stance toward this humanitarian emergency. However, newcomers still struggle to get access to basic needs in the city. We have conducted a face-to-face, cross-sectional survey to collect …


Nutritional Management Of Low Birth Weight And Preterm Infants In Low- And Low Middle-Income Countries, Maha Azhar, Rahima Yasin, Sawera Hanif, Sharib Afzal Bughio, Jai K. Das, Zulfiqar Ahmed Bhutta Jan 2025

Nutritional Management Of Low Birth Weight And Preterm Infants In Low- And Low Middle-Income Countries, Maha Azhar, Rahima Yasin, Sawera Hanif, Sharib Afzal Bughio, Jai K. Das, Zulfiqar Ahmed Bhutta

Institute for Global Health and Development

Introduction: Preterm and low birth weight (LBW) infants are at an increased risk of morbidity and mortality compared with their term counterparts, with more than 20 million LBW infants born each year, the majority in lower middle-income countries (LMICs). Given the increased vulnerability and higher nutritional needs of these infants, optimizing feeding strategies may play a crucial role in improving their health outcomes.
Methods: We updated evidence of Every Newborn Series published in The Lancet 2014 by identifying relevant systematic reviews, extracting low-income country (LIC) and LMIC data, and conducting revised meta-analysis for these contexts.
Results: We found 15 reviews; …


‘Like A 6-Year-Old Dropped On Mars Without Parents’: Faculty Members’ Intercultural Competence And Cultural Adaptation In The Uae, Mustafa Aydogan, Esra İzmir, Hana Shahin Jan 2025

‘Like A 6-Year-Old Dropped On Mars Without Parents’: Faculty Members’ Intercultural Competence And Cultural Adaptation In The Uae, Mustafa Aydogan, Esra İzmir, Hana Shahin

All Works

This study examines the intercultural competence and sociocultural adaptation of international faculty members (IFMs) in the United Arab Emirates (UAE), a highly multicultural educational setting. Using a mixed-methods approach, the study explores IFMs’ adaptation experiences and the impact of multicultural teaching training. Quantitative analysis of 167 IFMs revealed a significant relationship between intercultural competence and sociocultural adaptation, with training enhancing both. Participants from Muslim or Arab backgrounds adapted better, emphasizing the role of cultural familiarity with the host culture. Qualitative findings from 14 interviews identified five key themes: (a) UAE’s diverse environment, (b) cultural distance, (c) language and communication challenges, …


A Systemic Analysis Of Helicopter Instructional Accidents In The United States From 2010 To 2022, Gustavo Sanchez Cortes, Dimitrios Ziakkas, Mary E. Johnson Jan 2025

A Systemic Analysis Of Helicopter Instructional Accidents In The United States From 2010 To 2022, Gustavo Sanchez Cortes, Dimitrios Ziakkas, Mary E. Johnson

Journal of Aviation/Aerospace Education & Research

A high number of accidents during helicopter training in the United States (U.S.) highlights the need for research to investigate their causal and contributing factors. In this retrospective study, researchers analyzed helicopter instructional accidents reported in the National Transportation Safety Board (NTSB) Case Analysis and Reporting Online (CAROL) database. The Systems Theoretic Accident Model and Processes (STAMP) and Systems-Theoretic Process Analysis (STPA) methodologies were used to identify hazards and unsafe control actions in helicopter training, using autorotation maneuvers as a case study. Helicopter instructional flights in the U.S. accounted for 299 accidents between 2010 and 2022, with an average accident …


Suas Agricultural Aerial Application Operational Field Test, David Thirtyacre, Joseph Cerreta, Scott S. Burgess Jan 2025

Suas Agricultural Aerial Application Operational Field Test, David Thirtyacre, Joseph Cerreta, Scott S. Burgess

International Journal of Aviation, Aeronautics, and Aerospace

One of the most promising uses of aerial applications by a sUAS is on small farms where traditional crewed aerial applicators were not practical due to the limited size of the operations. This controlled field test aimed to assess the feasibility and cost-effectiveness of using a sUAS spreading system compared to the traditional manual application of weed killer and fertilizer on cranberry bogs in Western Washington that were less than 10 acres. The aerial application took place over two separate days as scheduled by the farmer for maximum product efficiency. A total of sixty-three flights were necessary to apply the …