Holographic Sensors For The Detection Of Volatile Organic Compounds, Graceson Antony

Doctoral

Volatile organic compound (VOC) monitoring at parts-per-million (ppm) concentration levels is essential for occupational safety, indoor air quality, and regulatory compliance. Although holographic gas sensors have been widely investigated, most operate in reflection mode as qualitative visual indicators, with limited quantitative evaluation of sensing mechanisms and scarce systematic demonstrations of repeatable multi-cycle validation for VOCs at ppm concentrations. A physics-based optimisation framework for transmission-mode holographic gas sensors which can bridge this gap has remained largely undeveloped.

This thesis presents the development and optimisation of real-time transmission-mode volume phase transmission holographic grating (VPTHG) sensors for ppm-level VOC detection. A comprehensive theoretical …

Subjective Glib Dynamics: Using An Alien Society To Investigate Reactions To Leader And Member Norm Deviance, Catie Burtch

Cal Poly Humboldt theses and projects

Social groups are built by members and leaders who form consensus on the defining attributes of their groups. Individual group members look to senior members and leaders to learn what it means to be a member of that group. Thus, norm maintenance is an important aspect of group health. The subjective group dynamics model details the specific group contexts under which people derogate ingroup members for transgressing norms. However, ingroup leaders are treated differently from regular group members and are given leniency for their transgressions. The current research extends these two bodies of work by directly comparing the consequences of …

Geographic Variation In Proteomic Responses To Ocean Acidification In A Cold-Water Coral (Balanophyllia Elegans), Keana A. Richmond

Cal Poly Humboldt theses and projects

In the face of a rapidly changing climate, assessing organismal responses to future stressors in the context of current, natural exposure to stress could provide key insights to understanding marine ecosystem resilience. I used Balanophyllia elegans, a cold-water, solitary, azooxanthellate coral as a model to better understand how varying oceanographic conditions across its geographic range have shaped its ability to tolerate and potentially adapt to current and future ocean acidification conditions. I collected B. elegans individuals from four sites across 2,500km of their range and subjected them to two pH treatments to investigate site-specific protein expression in response to …

Early Successional Response To Stream Daylighting In Redwood National And State Parks, Orick, California, Rylee Rawson

Cal Poly Humboldt theses and projects

In-channel stream restoration projects can act as both disturbance and recovery mechanisms, disrupting existing conditions to reestablish the hydrologic and ecological processes that sustain stream ecosystems. These interventions initiate successional trajectories in which channel form and biological communities reorganize over time. In Redwood National and State Parks (California, USA), the Redwoods Rising initiative restores buried headwater channels by recontouring legacy logging roads and daylighting streams buried by Humboldt crossings. Using the National Park Service Klamath Network wadable stream monitoring protocol, I evaluated nine restored reaches spanning one to five years post-restoration, alongside old-growth reference reaches and available pre-treatment data. I …

Assessing Coho Salmon (Oncorhynchus Kisutch) Distribution Using Traditional Sampling Methods In Conjunction With Edna On Trinity River Tributaries Within The Hoopa Tribal Boundaries, Ely D. Boone

Cal Poly Humboldt theses and projects

Detecting the presence of species using environmental DNA (eDNA) is a fast-growing field of study that shows much promise for population monitoring. In fisheries biology, eDNA is a potentially powerful tool compared to traditional fisheries monitoring techniques such as visual observation via snorkel surveys. When eDNA and traditional survey methods are employed in tandem, using the same spatial and temporal sampling design, eDNA often detects target species when traditional methods do not. In this study, instead of utilizing this paired study design, I implemented eDNA and snorkel surveys at different sampling scales with eDNA being collected at a single downstream …

Supporting Risky Outdoor Play Through Professional Development: A Quasi-Experimental Study Of Tk–6 Educators’ Attitudes, Justin Ross Burrill

Cal Poly Humboldt theses and projects

Children’s opportunities for active outdoor risky play have declined in many educational settings, despite evidence that manageable risk supports physical activity, self-regulation, confidence, resilience, and social participation. Educator attitudes and school culture may play an important role in determining whether children are offered developmentally appropriate opportunities for challenge, exploration, and autonomy. This quasi-experimental, single-group pretest-posttest study examined whether participation in a single-session professional development workshop was associated with changes in educators’ tolerance of risk in children’s play. Thirty educators attended a workshop focused on risky play, hazard-risk differentiation, inclusion of children with disabilities, loose-parts play, environmental affordances, and practitioner-informed implementation …

Contribution Of Lagoon-Rearing Juvenile Chinook Salmon (Oncorhynchus Tshawytscha) To The Adult Spawning Population In The Mattole River, Emma Held

Cal Poly Humboldt theses and projects

Bar-built estuaries are rivermouth confluences characterized by periods of disconnection between the river and the ocean due to a sandbar that builds across the mouth. Sandbar timing characteristics vary between years and between systems, but when closed, a lake-like lagoon forms in the estuary footprint. The Mattole River has a bar-built estuary that forms in late spring or early summer, often overlapping with juvenile Chinook salmon outmigration. Juveniles that do not leave the river before the bar closes must remain in the lagoon until the mouth opens in fall. The purpose of this thesis was to understand if lagoon-rearing is …

A Framework For Evaluating Riparian Climate Refugia In The Eel River Watershed, California, Farrah Tyler

Cal Poly Humboldt theses and projects

Climate change is increasing the need to identify and protect landscapes that support biodiversity through both habitat connectivity and climate refugia. Climate refugia are areas that remain relatively buffered from regional climatic change, enabling species to persist despite shifting environmental conditions. Riparian ecosystems can function as both movement corridors and climate refugia, yet methods for identifying these features and understanding the environmental processes that sustain them remain limited. In California's North Coast region, the identification and conservation of watersheds that may serve as climate refugia for sensitive plant and animal species will be essential for long-term ecosystem management and conservation. …

Preparing For Long-Acting Technologies: A Multistate Analysis Of Prep Persistence And Hiv And Sti Lab Coverage Among Oral Prep Initiators In St. Louis, Missouri (2014-2021), Lindsey M Filiatreau, Rupa Patel, Kate Curoe, Ashley Underwood, Joseph Cherabie, Elvin H Geng, Aditi Ramakrishnan, Rachel Presti, Aaloke Mody

2020-Current year OA Pubs

BACKGROUND: Engagement in pre-exposure prophylaxis (PrEP) care and routine screening for HIV and sexually transmitted infections (STIs) is critical to realizing the full benefits of this HIV prevention strategy.

METHODS: We enrolled a cohort of individuals seeking PrEP services in two clinics in Missouri, an Ending the HIV Epidemic priority state, from June 2014 to November 2021. We used electronic health record and survey data to explore outcomes in the 2 years following linkage to care using multistate methods. We assessed transitions between eight mutually exclusive care states differentiated by receipt of a prescription, lab coverage status, and retention. We …

Perceptions Of Georgia Elementary School Administrators Toward Elementary Agricultural Education, Addie Tucker

Murray State Theses and Dissertations

Elementary agricultural education (EAE) is a growing component of K-12 agricultural education, yet limited research exists on how school leaders perceive its value. The purpose of this study was to explore the perceptions of Georgia elementary school administrators regarding the implementation and value of EAE programs. Specifically, this study examined elementary principals’ and district superintendents’ views on the benefits, effectiveness, and value of EAE. A descriptive research design was used. Georgia elementary principals and district superintendents with active EAE programs during the 2025-2026 academic year were surveyed in the fall of 2025. The sample consisted of 18 principals and 18 …

Identifying The Knowledge And Skills That Students Enrolled In Agricultural Systems Technology Degree Programs Need: Perspectives From University Faculty, Jerry Blake Kennedy

Murray State Theses and Dissertations

National trends have highlighted the need for a knowledgeable, skilled workforce in advanced agricultural systems. University-level Agricultural Systems Technology (AST) undergraduate degree programs and closely-related degree programs are vital to equipping the agricultural workforce with the knowledge and skills needed to support the industry. Ensuring that AST curricula are relevant and appropriate is vital to equipping undergraduate students in such programs with the knowledge and skills they need to succeed in the modern agricultural workforce. This study sought to identify the essential knowledge and skills needed by undergraduate AST degree program students from the perspectives of university-level faculty across the …

The Effect That Positive And Negative Self-Concepts Have On Adolescents' Behavior And Personalities, Portia L. Davis

Murray State Theses and Dissertations

Abstract

The development stage of adolescence is a complex process in which adolescents begin to explore their identity and form either a positive or negative self-concept. Self-concept plays a crucial role in shaping adolescents' personalities and behaviors. Self-concept includes how adolescents view themselves and how others see them. An adolescent's self-concept can influence their self-confidence, social relationships, and decision-making abilities. This study examines the relationship between overall self-concept and adolescents' personality traits and behaviors. To gather this information, a quantitative research design is used, in which adolescents complete assessments such as the Tennessee Self-Concept Scale (TSCS), the Woodcock-Johnson IV (WJ-IV), …

Classifying Surfaces With Handle Decomposition, Elizabeth Sipes

Murray State Theses and Dissertations

Among topological spaces, manifolds draw a lot of interest. An
n-manifold is a space that is locally like R^n. Manifolds of dimension 2
are called surfaces. Using handle decomposition, we decompose surfaces
into k-handles, where 0< =k< =2. Techniques such as handle sliding and
handle cancellation allow us to get a more favorable representation of
our surface. We use these tools and calculation of the fundamental group
to classify all compact surfaces.

Academic Growth From Preact To Act: The Influence Of Socioeconomic Status And Attendance In A Rural Alabama High School, Stacy L. Tinch

Murray State Theses and Dissertations

The purpose of this quantitative correlational study was to examine academic growth from the PreACT to the ACT among students attending a rural public high school in Alabama and to investigate whether socioeconomic status (SES) and attendance were associated with differences in that growth. Guided by Opportunity-to-Learn Theory, the study explored whether students demonstrated academic growth during high school and whether SES, attendance, or the interaction between these variables influenced growth outcomes. Archival student-level data were collected from four graduating cohorts. The final sample consisted of 384 students with complete records for PreACT scores, ACT scores, attendance, and socioeconomic status. …

An Analysis Of Systemic And Contact Herbicide Usage Trends In Illinois Corn Production Systems, Paige E. Mckittrick

Murray State Theses and Dissertations

Herbicide use is central to weed management in Illinois corn production; however, long-term changes in the balance between systemic and contact herbicides have not been well quantified at the statewide scale. This study analyzes herbicide trends in Illinois corn from 1982 to 2016 using secondary data from the USDA Agricultural Chemical Use Survey, paired with climate, regulatory, and herbicide resistance information. Herbicide active ingredients were classified into systemic and contact functional categories and grouped according to Weed Science Society of America (WSSA) mode-of-action (MOA) codes. For each survey year, total herbicide load (lb a.i./acre), functional proportions, MOA-specific contributions, and a …

The Impact Of Congenital Heart Disease On The Timing Of Alzheimer's Disease In Down Syndrome, Julianne G Clina, Beau Ances, Et Al.

2020-Current year OA Pubs

INTRODUCTION: The incidence of Alzheimer's disease (AD) in Down syndrome (DS) exceeds 90%. Approximately 50% of people with DS have congenital heart disease (CHD). Having CHD increases risk for early-onset AD in populations without DS, but it is unclear if CHD influences AD in DS.

METHODS: Data from the Alzheimer Biomarker Consortium-Down Syndrome (ABC-DS) were used. Participants with CHD (

RESULTS: People with CHD scored lower for visuospatial ability (

DISCUSSION: Presence of CHD may influence AD progression in DS.

HIGHLIGHTS: In adults with Down syndrome (DS), those with congenital heart disease (CHD) had higher amyloid beta and reached the …

Availability And Utilization Of School Library Resources And Its Impacts On The Academic Excellence Of Secondary School Students In Edo State., Iyobosa Ewere Mrs., Ben Asuquo, Glory Mbah Mrs.

Library Philosophy and Practice (e-journal)

The study examines availability, and utilization of school library resources and its impacts on the academic excellence in secondary school libraries in Edo state. The descriptive survey research was adopted for the study. The population of the study was 2162 senior secondary school students from Idia Girls’ College, Boiling Point Academy and UNIBEN Demonstration Secondary School. The sampling techniques used for the study was Random Sampling Technique, a total of 216 respondents was used as the sample size representing 10% of the total population. A well structured questionnaire was designed and distributed to respondents .A total of 216 copies of …

Mapping Robusta Coffee (Coffea Canephora) Cropping Systems In Uganda: A Two-Step Pixel And Sub-Pixel Based Approach With Sentinel-2 Data, Getachew Kebede, Bester Tawona Mudereri, Onisimo Mutanga, Tobias Landmann, John Odindi, Natacha Motisi, Fabrice Pinard, Henri E.Z. Tonnang, Elfatih M. Abdel-Rahman

All Peer-Reviewed Publications

Coffee is a highly valued commodity and a widely consumed beverage, playing an important role in global trade. However, coffee farming landscapes are increasing transitioning into smaller-scale agricultural setups. This transformation highlights the critical need for accurate classification and mapping of coffee cropping systems (CS), especially in countries like Uganda, where dense vegetation and complex terrain present substantial challenges to traditional land survey methods. Moreover, understanding the spatial distribution of Robusta coffee (Coffea canephora) CS is essential for developing site-specific management strategies, guiding extension services, and informing evidence-based policy decisions. To address this gap, the present study aimed to enhance …

Pathways, Outputs And Impact Of Nih-Supported Bioinformatics And Genomics Graduate Trainees In Africa, Daudi Jjingo, Andrew Walakira, Suhaila Hashim, Cisse Cheickna, Ronald Galiwango, Caleb Kibet, Florence N. Kivunike, Gerald Mboowa, Fredrick Elishama Kakembo, Babajide Ayodele, Jean Baka Domelevo Entfellner, Santie De Villiers, Karen Wambui, Segun Fatumo, Tinashe Chikowore, John Mukisa, Alfred Ssekagiri, Nicholas Bbosa, Julius Mulindwa, Samuel Kyobe, Mike Nsubuga, Grace Kebirungi, Eric Katagirya, Savannah Mwesigwa, Ibra Lujumba, Rogers Kamulegeya, Samuel Kirimunda, Stephen Kanyerezi, Shahiid Kiyaga, Ivan Sserwadda, Davis Kiberu, Daniel Masiga

All Peer-Reviewed Publications

Global biomedical and health research is increasingly relying on genomic and computational approaches, largely driven by the increasing volumes of nucleic acid sequencing. Concurrently, epidemiological studies and clinical records are generating enormous amounts of data amenable to disease modeling, machine learning, and artificial intelligence techniques. Bioinformatics and data science expertise is therefore essential for improved population health. Accordingly, in 2012, the US National Institutes of Health (NIH) in partnership with the Wellcome Trust, and with support from the African Society for Human Genetics, initiated the H3Africa (Human Heredity and Health in Africa) consortium. One of its key goals was to …

First Record Of Arrhenophagus Chionaspidis Aurivillius (Hymenoptera: Encyrtidae) Parasitizing White Mango Scale In Kenya: Its Potential Distribution And Prospects In Biocontrol, Francis Obala, Abdelmutalab G.A. Azrag, Rehemah Gwokyalya, Shepard Ndlela, Ingo Grass, Georg Petschenka, Sunday Ekesi, Samira A. Mohamed

All Peer-Reviewed Publications

The white mango scale, Aulacaspis tubercularis Newstead (Hemiptera: Diaspididae), is one of the most destructive pests of mango worldwide. Its current management in most of the invaded areas largely depends on the intensive use of chemical insecticides. Biological control using parasitoids represents one of the most effective and environmentally sustainable management options. However, in Kenya, one of Africa's leading mango-producing countries, no effective parasitoid species associated with A. tubercularis had previously been recorded. This study aimed to identify encyrtid parasitoids associated with A. tubercularis in Kenya, and to assess how bioclimatic factors influence their occurrence and habitat suitability. Mango leaves …

Effects Of Temperature On The Life-History Traits Of Myzus Persicae And Its Efficiency In Transmitting Potato Virus Y (Pvy) In Potato Crops, Bonoukpoè M. Sokame, Henri E. Tonnang, Heidy Gamarra, Pablo Carhuapoma, Jan Kreuze, Leah R. Johnson, Ali Arab, Peter A. Armbruster, Oswaldo C. Villena

All Peer-Reviewed Publications

Aphids are highly sensitive to temperature changes and play a crucial role in transmitting plant viruses, accounting for the transmission of more than 50% of viruses that cause disease in crops. Among them, Myzus persicae is a major global pest, affecting over 400 plant species and transmitting more than 100 plant viruses, including potato virus Y (PVY), which poses a severe threat to potato crops. This study examines how temperature influences the life-history traits of M. persicae and its efficiency in transmitting PVY. Our research revealed that temperature significantly affects developmental duration, survival, and fecundity of M. persicae. The aphids …

Impact Of Environmental Microparticles On Insect Olfaction, Steve B.S. Baleba, Danube K.N. Wandji, Yves H. Tchiechoua, Komi Mensah Agboka, Iman B. Hassaballa, Victor O. Omondi, Beatrice T. Nganso, Saliou Niassy, Souleymane Diallo, Merid N. Getahun

All Peer-Reviewed Publications

Terrestrial insects underpin key ecosystem services, including pollination, herbivory regulation, decomposition, nutrient cycling, and disease control. These functions depend on chemical communication that guides insects to food, mates, hosts, shelters, and oviposition sites while helping them avoid threats. Environmental microparticles, such as micro- and nanoplastics, tyre wear particles, soot, mineral dust, and agricultural residues, are now widespread across air, soil, vegetation, and indoor environments, exposing insects through contact, deposition, and ingestion. Growing evidence shows that these particles disrupt insect olfaction by adsorbing volatile compounds, blocking antennal sensilla, and interfering with receptor and neuronal processes. These disruptions impair foraging, mating, oviposition, …

Thermal Requirements And Phenology Modelling Of A Drosophila Suzukii Population: Implications For Pest Risk Under A Changing Climate, Shepard Ndlela, Abdelmutalab G.A. Azrag, Esther Owino Awuor, Ibrahim Maholidy Farid, Samira Abuelgasim Mohamed

All Peer-Reviewed Publications

Drosophila suzukii (spotted-wing drosophila) is an invasive pest causing significant economic losses in soft-skinned fruit crops globally. This study presents comprehensive temperature-dependent life table data and phenology models for an African D. suzukii population collected in Kenya. Developmental time, mortality, fecundity, and adult longevity were assessed under constant temperatures from 12 to 30 °C. Using Insect Life Cycle Modelling (ILCYM) software, linear and nonlinear models were applied to characterise the effects of temperature on life history traits. Additionally, spatial risk indices including Establishment Risk Index (ERI), Generation Index (GI), and Activity Index (AI) were mapped globally for current and future …

Exploring Slow-Release Plasma Nitrogen Nano-Fertilizer For Improved Maize Production And Nutrient Use Efficiency, Stewart Kyebogola, Richard Onwonga, Stella Kabiri, Onesimus Semalulu, Swidiq Mugerwa, Russell Shelley Yost, Samuel Ikendi, Dennis Beesigamukama, Julius Opio, Godfrey Sseruwu

All Peer-Reviewed Publications

The use of nitrogen (N) fertilizer in maize production is constrained by scarcity, low use efficiency, and high costs. Plasma technology presents a more environmentally friendly nitrogen source (PN). When incorporated into nanocellulose composites to control fertilizer release (NPN), they improve N supply and mitigate environmental risks, thereby optimizing benefits. However, the productivity of NPN relative to urea and its nanoform (NU) remains unexplored. Screenhouse and field experiments were conducted twice on maize using five fertilizer treatments: control, urea, PN, NU, and NPN. All treatments were applied once at 66 kg N ha^-1 and replicated four times. Maize cultivated …

Response To Panos Tsoukalis, James K. Galbraith

Emancipations: A Journal of Critical Social Analysis

No abstract provided.

Review Of James K. Galbraith And Jing Chen, Entropy Economics: The Living Basis Of Value And Production (The University Of Chicago Press, 2025), Panos Tsoukalis

Emancipations: A Journal of Critical Social Analysis

No abstract provided.

Maximizing Online Intersession Enrollment Through Targeted Course Offerings, Heather S. Mcmillan, Charles D. Mcallister

Journal of the North American Management Society

Abstract

Online winter intersession courses have become an increasingly important strategy for universities seeking to support accelerated student progression while generating incremental tuition revenue. This study examines ten years of winter intersession enrollment data from a public, master’s-level comprehensive university in the Midwestern United States to identify course characteristics associated with higher student enrollment. Using 12,520 individual enrollment records, the analysis focuses on course type (general education versus major requirement), course classification (lower level, upper level, blended undergraduate/graduate, and graduate), and course discipline. A series of ANOVAs and Bonferroni post-hoc tests reveal significant differences in enrollment across these dimensions, with …

Bibliometric Analysis: Publish Or Perish And Vosviewer For Research Trends On Online Violence (2023–2025), Indriyana Rachmawati, Widya Juwita Sari, Sesya Dias Mumpuni

Buletin Konseling Inovatif

Cases of online violence have become increasingly widespread since the end of the COVID-19 pandemic, during which individuals began to grow dependent on the digital world. The digital realm has become a fundamental aspect of human life, bringing with it new forms of online violence. Online violence such as threats, hate speech, harassment, and bullying has emerged as a new weapon to control, isolate, and even torment affected victims. However, only a small body of literature has explored the changing nature of online violence following COVID-19. This study aims to review the literature on patterns of online violence post-pandemic, focusing …

Validation Of Micro Digital Content Model Of Project-Based Learning For Guidance And Counseling Courses In Non-Formal Education, Ella Faridati Zen, Yuliati Hotifah, Riskiyana Prihatiningsih, Nur Mega Aris Saputra

Buletin Konseling Inovatif

The research aims to produce a product in the form of a learning device for guidance and counseling courses in non-formal education in the form of micro digital based on project-based learning, which is theoretically accepted through expert testing. The development method uses the ADDIE design, with the procedures of Analysis, Design, Development, Implementation and Evaluation. The trial subjects or product assessors consist of material experts and media experts in the field of guidance and counseling. Data were collected with expert assessment instruments and analyzed using the average technique. The expert assessment of the product by material experts produced an …

Instagram Sebagai Ruang Cyberbullying Untuk Memenuhi Kebutuhan Gaya Hidup Hedonis Siswa Sekolah Menengah Atas, Elcindi Lazuardin Zamzamima, Im Hambali, Rizka Apriani

Buletin Konseling Inovatif

Recently, social media has been an integral part of adolescents’ life, serving as a medium for their self-actualization. On the other hand, adolescents use social media for hostile activities, such as bullying. This study describes Instagram as a platform for cyberbullying as it allows students to demonstrate their hedonist lifestyle. In this study, we used a descriptive qualitative approach. For the data collection, we involved two senior high school students, who were selected through purposive sampling with the criteria of undertaking cyberbullying acts to fulfill their needs for a hedonist lifestyle. The data were collected through structured interviews and documentation. …