Digital Commons Network^™

Evaluation Of Deep Learning-Based Multiparametric Mri Oropharyngeal Primary Tumor Auto-Segmentation And Investigation Of Input Channel Effects: Results From A Prospective Imaging Registry, Kareem A Wahid, Sara Ahmed, Renjie He, Lisanne V Van Dijk, Jonas Teuwen, Brigid A Mcdonald, Vivian Salama, Abdallah S R Mohamed, Travis Salzillo, Cem Dede, Nicolette Taku, Stephen Y Lai, Clifton D Fuller, Mohamed A Naser

Faculty, Staff and Student Publications

Background/purpose: Oropharyngeal cancer (OPC) primary gross tumor volume (GTVp) segmentation is crucial for radiotherapy. Multiparametric MRI (mpMRI) is increasingly used for OPC adaptive radiotherapy but relies on manual segmentation. Therefore, we constructed mpMRI deep learning (DL) OPC GTVp auto-segmentation models and determined the impact of input channels on segmentation performance.

Materials/methods: GTVp ground truth segmentations were manually generated for 30 OPC patients from a clinical trial. We evaluated five mpMRI input channels (T2, T1, ADC, Ktrans, Ve). 3D Residual U-net models were developed and assessed using leave-one-out cross-validation. A baseline T2 model was compared to mpMRI models (T2 + T1, …

Exploiting Induced Vulnerability To Overcome Parpi Resistance And Clonal Heterogeneity In Brca Mutant Triple-Negative Inflammatory Breast Cancer, David J H Shih, Mei-Kuang Chen, Jun Yin, Daniel J Mcgrail, Hui Dai, Rongbin Wei, Jing Zhang, Wenjin Jim Zheng, Kim-Anh Do, Liuqing Yang, Mien-Chie Hung, Shiaw-Yih Lin

Faculty, Staff and Student Publications

Acquired resistance and clonal heterogeneity are critical challenges in cancer treatment, and the lack of effective computational tools hampers the discovery of new treatments to overcome resistance. Using high-throughput transcriptomic databases of compound perturbation profiles, we have developed a bioinformatic strategy for identifying candidate drugs to overcome resistance with combinatorial therapy. We devised this strategy during an investigation into the acquired resistance against PARP inhibitors (PARPi) in a triple-negative inflammatory breast cancer cell line. In this study, we derived multiple PARPi-resistant clones and characterized their transcriptomic adaptations compared to the parental clone. The transcriptomes of the resistant clones showed substantial …

Pld1 Promotes Reactive Oxygen Species Production In Vascular Smooth Muscle Cells And Injury-Induced Neointima Formation, Ming Cai, Ziqing Wang, Thi Thu Trang Luu, Dakai Zhang, Brian Finke, Jingquan He, Li Wei Rachel Tay, Gilbert Di Paolo, Guangwei Du

Faculty, Staff and Student Publications

Phospholipase D (PLD) generates the signaling lipid phosphatidic acid (PA) and has been known to mediate proliferation signal in vascular smooth muscle cells (VSMCs). However, it remains unclear how PLD contributes to vascular diseases. VSMC proliferation directly contributes to the development and progression of cardiovascular disease, such as atherosclerosis and restenosis after angioplasty. Using the mouse carotid artery ligation model, we find that deletion of Pld1 gene inhibits neointima formation of the injuried blood vessels. PLD1 deficiency reduces the proliferation of VSMCs in both injured artery and primary cultures through the inhibition of ERK1/2 and AKT signals. Immunohistochemical staining of …

The Current Status And Shortcomings Of Stereotactic Radiosurgery, Hunter Mehrens, Trang Nguyen, Sharbacha Edward, Shannon Hartzell, Mallory Glenn, Daniela Branco, Nadia Hernandez, Paola Alvarez, Andrea Molineu, Paige Taylor, Stephen Kry

Faculty, Staff and Student Publications

Background: Stereotactic radiosurgery (SRS) is a common treatment for intracranial lesions. This work explores the state of SRS treatment delivery to characterize current treatment accuracy based on treatment parameters.

Methods: NCI clinical trials involving SRS rely on an end-to-end treatment delivery on a patient surrogate (credentialing phantom) from the Imaging and Radiation Oncology Core (IROC) to test their treatment accuracy. The results of 1072 SRS phantom irradiations between 2012 and 2020 were retrospectively analyzed. Univariate analysis and random forest models were used to associate irradiation conditions with phantom performance. The following categories were evaluated in terms of how they predicted …

Automated Segmentation Of Colorectal Liver Metastasis And Liver Ablation On Contrast-Enhanced Ct Images, Brian M Anderson, Bastien Rigaud, Yuan-Mao Lin, A Kyle Jones, Hynseon Christine Kang, Bruno C Odisio, Kristy K Brock

Faculty, Staff and Student Publications

Objectives: Colorectal cancer (CRC), the third most common cancer in the USA, is a leading cause of cancer-related death worldwide. Up to 60% of patients develop liver metastasis (CRLM). Treatments like radiation and ablation therapies require disease segmentation for planning and therapy delivery. For ablation, ablation-zone segmentation is required to evaluate disease coverage. We hypothesize that fully convolutional (FC) neural networks, trained using novel methods, will provide rapid and accurate identification and segmentation of CRLM and ablation zones.

Methods: Four FC model styles were investigated: Standard 3D-UNet, Residual 3D-UNet, Dense 3D-UNet, and Hybrid-WNet. Models were trained on 92 patients from …

Contemporary Evidence On Colorectal Liver Metastases Ablation: Toward A Paradigm Shift In Locoregional Treatment, Yuan-Mao Lin, Reto Bale, Kristy K Brock, Bruno C Odisio

Faculty, Staff and Student Publications

Image-guided percutaneous ablation techniques represent an attractive local therapy for the treatment of colorectal liver metastases (CLM) given its low risk of severe complications, which allows for early initiation of adjuvant therapies and spare functional liver parenchyma, allowing repeated treatments at the time of recurrence. However, ablation does not consistently achieve similar oncological outcomes to surgery, with the latter being currently considered the first-line local treatment modality in international guidelines. Recent application of computer-assisted ablation planning, guidance, and intra-procedural response assessment has improved percutaneous ablation outcomes. In addition, the evolving understanding of tumor molecular profiling has brought to light several …

Metal Coordinating Inhibitors Of Rift Valley Fever Virus Replication, Elizabeth Geerling, Mohamed Elagawany, Bahaa Elgendy, Et Al

2020-Current year OA Pubs

Rift Valley fever virus (RVFV) is a veterinary and human pathogen and is an agent of bioterrorism concern. Currently, RVFV treatment is limited to supportive care, so new drugs to control RVFV infection are urgently needed. RVFV is a member of the order Bunyavirales, whose replication depends on the enzymatic activity of the viral L protein. Screening for RVFV inhibitors among compounds with divalent cation-coordinating motifs similar to known viral nuclease inhibitors identified 47 novel RVFV inhibitors with selective indexes from 1.1-103 and 50% effective concentrations of 1.2-56 μM in Vero cells, primarily α-Hydroxytropolones and N-Hydroxypyridinediones. Inhibitor activity and selective …

Cell-Directed Aptamer Therapeutic Targeting For Cancers Including Those Within The Central Nervous System, Jun Wei, Renduo Song, Aria Sabbagh, Anantha Marisetty, Neal Shukla, Dexing Fang, Hinda Najem, Martina Ott, James Long, Lijie Zhai, Maciej S Lesniak, Charles David James, Leonidas Platanias, Michael Curran, Amy B Heimberger

Faculty, Staff and Student Publications

Osteopontin (OPN) is produced by tumor cells as well as by myeloid cells and is enriched in the tumor microenvironment (TME) of many cancers. Given the roles of OPN in tumor progression and immune suppression, we hypothesized that targeting OPN with aptamers that have high affinity and specificity could be a promising therapeutic strategy. Bi-specific aptamers targeting ligands for cellular internalization were conjugated to siRNAs to suppress OPN were created, and therapeutic leads were selected based on target engagement and

The Perspectives Of Former Csec On The Recruitment Process Through Online Platforms, Shawnte Beacham-Houston

Walden Dissertations and Doctoral Studies

Commercial sexual exploitation of children (CSEC) is the sexual exploitation of children for financial gain and is a billion-dollar industry. The sexual exploitation of children is a serious form of sexual abuse and a violation of their human rights. Previous research has explored sex trafficking victimization but not pathways to sexual exploitation. Current research does not explain how online activities and specific internet platforms are involved in CSEC recruitment and entry into the commercial sex trade industry. In this study, the way in which social media platforms are used to recruit children into the sex trade industry was addressed. The …

Lived Experiences Of Life Partners Of Police Officers Working In Crimes Against Children Units, Maria Beagle

Walden Dissertations and Doctoral Studies

Police stress is an ongoing concern in law enforcement; however, limited research has demonstrated how work-related stress affected life partners of police officers. According to Selye’s stress theory, the occupational demands placed on individuals can negatively impact their personal lives and their relationships. Law enforcement officers, especially those working cases that are sexual in nature, experience significant emotional distress. This study sought to examine the lived experiences of the partners of those who work in Crimes Against Children (CAC) units. CAC units include investigative evidence that has been considered traumatic. Specific examination of stress that life partners experience was conducted …

Fortitude, Spiritual Fortitude, And The Cancer Care Continuum In African American Breast Cancer Survivors, Karen Y. Boone

Walden Dissertations and Doctoral Studies

African American breast cancer survivors (AABCS) struggle with physical, emotional, psychological, spiritual, and financial challenges. Navigating these challenges can require the use of inner resources such as fortitude and spiritual fortitude. Using Folkman and Lazarus’ transactional model of stress and coping as the theoretical framework, the purpose of this study was to examine fortitude and spiritual fortitude as coping responses by African American women living with breast cancer and whether fortitude and spiritual fortitude were associated with phases of the cancer care continuum. A quantitative nonexperimental cross-sectional design was used for primary data collection that involved using Pretorius’ Fortitude Questionnaire …

Dispositional Joy As A Mediator Of Adverse Childhood Experiences And Parental Reflective Functioning, Mollie Brady

Walden Dissertations and Doctoral Studies

Parental reflective functioning (PRF) is a critical contributor to positive parenting outcomes. Early adverse experiences are a significant risk factor for insensitive parenting practices and poor PRF. Researchers have found that positive emotions, such as dispositional joy (DJ), influence both parenting outcomes and building resilience to stressful events. Adverse childhood experiences (ACEs), DJ, and PRF have been studied extensively in the literature as separate or paired constructs. However, to date, no studies have examined how these variables interact with each other. The purpose of this quantitative study was to explore the relationship between ACEs, DJ, and PRF, and the mediating …

Obesity's Impact Among Asian Americans In Southern California, Alyssa Mae Sunga Carlos

Walden Dissertations and Doctoral Studies

Obesity continues to be an important public health issue in the United States, especially among minority populations. However, one minority group experiences the lowest obesity rate: Asian Americans. As a result, there is not much research available involving the impact of obesity and weight gain among this population. The purpose of this basic qualitative exploratory study was to improve the understanding of obesity’s impact on the Asian American population, specifically in Southern California, whose goals were to lose weight and become more informed about obesity’s impact on health. The study consisted of three main research questions. Twenty-five participants were interviewed …

Understanding Effective Parental Involvement Activities Across Ses, Monique Antoinette Carrington Young

Walden Dissertations and Doctoral Studies

Parental involvement is pivotal for impoverished middle school students to achieve academic achievement. The purpose of this study was to evaluate the relationship of parental involvement activities and academic achievement for impoverished middle school students. Epstein’s six parental involvement types was the theoretical framework for the research study. The six independent variables of parental involvement were parenting, volunteering, learning at home, decision making, communicating, and collaborating with community The relationship for each parental involvement activated to academic achievement as measured by grade point average was evaluated. A quantitative research design was applied using archival data from the U.S. Department of …

Experiences Of Mechanical Circulatory Support Patients With Primary Implant Education, Dawn Michelle Christensen

Walden Dissertations and Doctoral Studies

Advancement in mechanical circulatory support (MCS) device therapy has led to increased use in heart failure therapy and relies on optimized patient education for successful support. The purpose of this 3-manuscript study, guided by the Husserlian transcendental phenomenological method, was to explore the lived experiences of (a) patients with primary mechanical circulatory support education (PMCSE), (b) patients who undergo unplanned MCS implantation with PMCSE, and (c) patients who undergo planned MCS implantation with PMCSE. Eleven participants were recruited (eight planned, three unplanned) from MCS targeted social media sites and interviewed using a semistructured open-ended question format. Data were analyzed using …

Physician Authentic Leadership As Health Care Managers And Its Impact On Subordinates’ Ethical Strength, Eddie M. Christian

Walden Dissertations and Doctoral Studies

Physicians exercising the characteristics of authentic leaders may be better equipped to affect the ethical strength of health care staff and provide a vehicle for reducing corruption in the health care industry. This position suggests that physicians practicing with these particular qualities are more effective than those who are not genuine, transparent, or committed to maintaining emotional balance in their work relations. The purpose of this quantitative correlational study was to determine whether physician authentic leadership (AL) moderated the relationship between physician emotional intelligence (EI) and the moral potency of their billing and codes managers. Survey data were collected from …

The Longevity Of A Law Enforcement Career Post Critical Incident, Alyce E. Clark

Walden Dissertations and Doctoral Studies

Law enforcement officers experience traumatic events that can have an impact on their health and their career. Regardless of the continued research on police and mental health, challenges persist. The stigma is that law enforcement officers are tough and keep their emotions to themselves; however, they are human, like the community they serve. Due to possible consequences related to officers discussing having mental health problems after critical incidents, police officers may be reluctant to seek help due to backlash. Interviews were completed in a two-tier format that led to follow-up questions with surveys specifically related to alcohol and burnout found …

A Qualitative Examination Of Single-Parent Matriarchal Homes’ Influence On Gang Membership, Darryl Edwards

Walden Dissertations and Doctoral Studies

There is a problem in the city of Chicago. Gangs are responsible for a substantial percentage of violent crimes in most jurisdictions. This study examined how and to what extent single-parent matriarchal households influenced African American men between 18 and 25 to join gangs in Chicago. This study’s theoretical foundations were matriarchal theory and critical race theory. This qualitative study’s research design is heuristic phenomenology design. An in-depth interview method was employed using purposeful and snowball sampling of 20 participants; in-depth interviews were conducted using telephone technology. This study, which investigated the connection between being raised in a single-parent matriarchal …

Adolescent Cyberbullying Program Experiences Of White Rural Males, Lonnie Lynn Erskine

Walden Dissertations and Doctoral Studies

Technology has become a gateway to use aggression against others. Cyberbullying is an ongoing problem, often causing severe mental, physical, and emotional issues. The purpose of this generic qualitative study was to explore the experiences of White rural males between the ages of 18–30 who experienced cyberbullying prevention and intervention programs when they were between the ages of 15–18. The research question directly addressed this purpose. Prevention and intervention can be powerful if utilized correctly, providing adolescents with assistance, safety, and assurance to cope with cyberbullying effectively. Vygotsky’s social development theory guided this study. Eight individuals participated in semistructured interviews. …

Perceptions Of Support For Adult Students At A Community College, Holle Lynn Ford

Walden Dissertations and Doctoral Studies

Adult college students face unique challenges that can derail their dreams of completing a degree or certificate program. The problem addressed in this study was that, although postsecondary institutions in Tennessee have been tasked with equipping at least 55% of adult residents with a college degree or certificate by the year 2025, some college leaders were struggling with how to best support adult students. Guided by Maslow’s hierarchy of needs theory, the purpose of this qualitative case study was to better understand what supports were needed to best meet the needs of adult students who are completing a degree or …

Predictors Of Radio Frequency Identification Adoption For Medication Administration In Hospitals, Sherita Freeman

Walden Dissertations and Doctoral Studies

Medication administration challenges within the United States hospital system have led to adverse drug events from medication errors among patients, resulting in 1.3 million emergency room visits and 350,000 hospitalizations annually. Radio frequency identification (RFID) has been identified as a useful tool within hospital systems; however, this technology has been slow to be incorporated to manage medication administration processes, necessitating exploration of predicting factors of RFID adoption. This quantitative, cross-sectional study explored the contributing factors of United States hospital’s adoption of RFID for medication administration using the technology-organization-environment framework as a foundation and secondary data from the Health Information Management …

Reporting Sexual Revictimization: The Decision-Making Process For Victims With Prior Reporting Experience, Jessica Paige Frye Holcomb

Walden Dissertations and Doctoral Studies

It is widely known that sexual assault is a pervasive global health issue. Victims of sexual assault face a greater risk of later being sexually revictimized. Despite its prevalence, sexual assault is the most underreported of violent crimes. Existing research has explored rates of formal and informal sexual assault disclosure, barriers, and motivators to report as well as survivor experiences withing the criminal justice process. However, the deciding factors for sexual assault victims in reporting revictimization or how any prior experience making a report may impact their decision to report subsequent assaults have not been studied previously. The purpose of …

Successful Strategies To Sustain Practice Changes In Healthcare, Erin Gable

Walden Dissertations and Doctoral Studies

Healthcare managers implement evidence-based practice to meet the growing needs of aging populations. However, many healthcare leaders fail to sustain newly implemented practices. Grounded in the promoting action on research implementation in health services conceptual framework, the purpose of this qualitative interpretative descriptive study was to explore strategies healthcare leaders use to sustain practice changes to meet increasing demands for quality care of the aging population. The participants included eight healthcare managers from Canada and the United States who led strategies to sustain practice change. The four themes that emerged using semistructured interviews and thematic analysis were staff buy-in, staff …

Novice Nurses’ Perceptions And Expectations Of What Constitutes Nursing Practice, Mcfrances Catherine George

Walden Dissertations and Doctoral Studies

AbstractAfter completing preceptorship programs, novice nurses work independently to provide patient care at the bedside. Novice nurses may leave bedside nursing with a minimum of 1 year of experience, resulting in vacant bedside nurse positions. These vacant positions are a problem because this could lead to low patient satisfaction, higher patient mortality rates, and failure to rescue in emergent cases. The purpose of this study was to explore the perceptions and expectations of nursing practice related to performance, demands, and requirements from novice nurses. Afaf Meleis's 1960 transition theory guided the understanding of novice nurses' perceptions and expectations of nursing …

Lived Experiences Of Crisis Counselors With Repeat Exposure To Mental Health Crises, Emily Genever

Walden Dissertations and Doctoral Studies

Due to the potentially traumatic content that crisis counselors face, members of the counselor education community must understand the psychological implications of repeated exposure to mental health crises to fulfill their responsibility of properly training, supervising, and supporting crisis counselors. The purpose of this qualitative phenomenological study was to explore the lived experiences of crisis counselors who had worked full-time with a variety of mental health emergencies. A hermeneutic design and constructivist self-development theoretical lens allowed for the illumination of the perceived positive and negative consequences of crisis work. Purposive sampling strategies were employed to recruit seven crisis counselors for …

Strategies For Increasing The Sustainability Of Small Restaurant Business, Sahara J. Givens-Evans

Walden Dissertations and Doctoral Studies

Small business owners who operate in the restaurant industry face many challenges and sometimes succumb to failures. Identifying solutions to avoid failure is important and will strengthen this community of entrepreneurs and help in terms of creating sustainability strategies. Grounded in Richard Cantillon’s entrepreneurship theory, the purpose of this qualitative multiple case study was to explore strategies small business owners in the restaurant industry use to sustain business beyond 5 years. Participants included six small restaurant business managers who survived beyond 5 years and specialized in fast-casual food service within Chicago. Data were collected using semi-structured interviews and participant reflections. …

Help-Seeking Behaviors For Depression Among Native Hawaiian Women In The Western Region Of The United States Mainland, Marlana Glover

Walden Dissertations and Doctoral Studies

Help-seeking for depression, as with other mental illnesses is contingent upon stigmas that one perceives. Although causes for depression differ among indigenous populations, native Hawaiians suffer from the Western acculturation and colonization of their homeland. With lack of trust in the U.S. healthcare system, many native Hawaiians are reluctant to seek help for depression. Furthermore, research has shown that most studies on native Hawaiians are conducted in their native environment when many Hawaiians relocate to the U.S. mainland. Because of the current depression crisis, it is critical to explore depression among native Hawaiians, particularly women on the mainland to see …

The Impact Of Agency Culture On A Supervisor's Modeling Of Self-Care To Social Workers, Lacey Maxwell Godsby

Walden Dissertations and Doctoral Studies

Supervision is a field standard in which experienced social workers assist other social workers by modeling practical skills and teaching self-care standards. However, an agency's culture has the potential to negatively affect a supervisor’s ability to model self-care to social workers in a mental health setting, which can in turn increase the risk of burnout and the potential for harm to the agency including decreased employee retention, decreased employee satisfaction, and lower quality client care. The purpose of this project was to explore how agency culture affected a supervisor’s ability to model necessary self-care techniques to social work professionals. Another …

Law Enforcement Officers' Experience Of Crisis Intervention Team (Cit) Training, Jessica Yolanda Goings

Walden Dissertations and Doctoral Studies

AbstractThe decline in mental health services has led to an increased role of law enforcement officers (LEOs), who are often the first to respond to mental health crisis incidents. Despite the specialized training that officers receive, there continues to be a public consensus that LEOs lack proficiency when handling a mental ill individual and have a deficiency in communication skills. The purpose of the research was to explore the experience of Crisis Intervention Team (CIT) training for LEOs and then describe how their experience ensued once deployed to the field to handle mental health encounters. Evaluations of CIT training have …

Continuity Of Care For Adult Offenders With Severe And Persistent Mental Illnesses: An Action Research Study, Lakeshia C. Gonzalez

Walden Dissertations and Doctoral Studies

For decades, the representation of adults with severe and persistent mental illnesses (SPMI) in the criminal justice system has steadily grown despite public recognition and increased federal implementation of mental health courts and diversion programs. Though more is known about risk factors associated with psychiatric and criminal recidivism among this population, a gap in the literature remains on collaborative interventions and continuity of care between inpatient mental health and criminal justice facilities. Grounded in resilience theory, the purpose of this qualitative study was to examine challenges social workers faced when attempting to facilitate discharge planning between inpatient mental health facilities …