All Faculty Deposits

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The "All Faculty Deposits" collection contains works deposited by faculty and appointed delegates from the Elements (EFARs) system. For help with Elements, see Frequently Asked Questions on the Provost's website. In general, items can only be deposited if the item is a scholarly article that is covered by Virginia Tech's open access policy, or the item is openly licensed or in the public domain, or the item is permitted to be posted online under the journal/publisher policy, or the depositor owns the copyright. See Right to Deposit on the VTechWorks Help page. If you have questions email us at vtechworks@vt.edu.

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Mirtazapine Induced Tardive Dyskinesia in an Older Adult
Syed, Amin; Soni, Karishma; Bankole, Azziza; Ratnakaran, Badr (Elsevier, 2025-10)
Mirtazapine, first sold in the United States as Remeron in 1996, is a noradrenergic and specific serotonergic antidepressant FDA-approved for major depressive disorder. Its mechanism of action is referred to as NaSSA due to its alpha-2, 5-HT2, and 5-HT3 antagonism. It has also been used off-label as a third-line treatment option for akathisia, appetite stimulation, and SSRIinduced sexual dysfunction. Incidents of hyperkinetic movement disorders caused by mirtazapine have been reported, but even more infrequent for cases involving tardive dyskinesia (TD). The aim of this presentation is to highlight a case of TD with the use of mirtazapine in an older adult and search for more literature involving mirtazapineinduced tardive dyskinesia.
Land subsidence on Java Island and its contributions to relative sea level change
Ohenhen, Leonard O.; Shirzaei, Manoochehr; Kumar, Praveen; Aditiya, Arif; Tiwari, Ashutosh; Davis, James L.; Kolawole, Folarin; Chaussard, Estelle; Sadhasivam, Nitheshnirmal; Dasho, Oluwaseyi; Zhong, Wen; James, Roselyn H.; Daramola, Samuel; Nicholls, Robert J.; Minderhoud, Philip S. J. (AAAS, 2026-04)
Rising sea levels and land subsidence combine to determine relative sea level (RSL) rise, which is intensifying coastal hazards. However, many densely populated regions lack the observational infrastructure to identify and quantify land subsidence contribution to RSL, hindering effective planning of responses. Here, we used satellite radar observations to generate a high-resolution assessment of land subsidence across Java Island, Indonesia, and evaluate its contribution to 21st-century RSL change. We identify widespread and temporally evolving subsidence with rates ranging from 1 to 15 cm/year in multiple coastal cities. Using machine learning spatiotemporal clustering and ancillary datasets, we attribute the dominant subsidence mechanisms to resource extraction across various geographic and geological settings. We further construct virtual tide gauges at 5-km intervals along the northern coastline, revealing that contemporary subsidence will dominate RSL budgets over the next 25 years along >75% of the coast. These findings underscore the urgent need to integrate subsidence into sea level risk and adaptation assessments in vulnerable coastal regions.
The Credibility Gap: Epistemic Injustice and Neurodivergence in U.S. Legal Contexts
Van Vorce, Hailey; Parti, Katalin; Armour, Chelsea; Edgin, Jamie O. (Sage, 2026-04-10)
Neurodivergent people, including individuals with intellectual and developmental disabilities, continue to face systemic barriers to meaningful and fair participation in the U.S. justice system. Legal standards governing competence, credibility, and culpability remain anchored in expectations of neurotypical communication and reasoning. These expectations do more than shape procedures; they define who is heard, believed, and ultimately brought to justice. This commentary examines forensic ableism, the privileging of neurotypical cognition and communication in legal contexts, through Fricker's framework of epistemic injustice, with a focus on testimonial injustice. In practice, credibility judgments are rooted in neurotypical norms that often devalue neurodivergent testimony. Across competency evaluations, credibility assessments, and capital sentencing decisions, disability-linked patterns of expression and interaction are frequently misinterpreted as signs of unreliability or diminished competence. Addressing forensic ableism requires the redesign of legal processes and broadened disability education to aid in the recognition of diverse cognitive and communication profiles as legitimate ways of knowing and participating. We call for reforms grounded in accessibility, epistemic humility, and collaboration with the neurodivergent community.
Was Sutherland right? An analysis of cryptocurrency offenders
Dearden, Thomas E.; Parti, Katalin; Hawdon, James E. (Emerald, 2026-04-09)
Purpose: The purpose of this study is to examine the applicability of conventional criminological theories to white-collar offenders involved in cryptocurrency-related market manipulation, specifically pump-and-dump schemes. Using Sutherland’s differential association (DA) framework as a theoretical foundation, this research tests whether demographic and theoretical factors – such as self-control, DA, anomie and strain – predict illegal financial behavior in emerging digital markets. Design/methodology/approach: Survey data from a national sample of US adults on the promotion of cryptocurrencies for financial gain were analyzed using t-tests and regression models. Findings: The findings of this study suggest that traditional theories of crime, including DA, anomie and strain, lose predictive significance when demographic variables are considered. High-income, male and younger individuals were most likely to engage in cryptocrime in general. Overall, the results of this study highlight the complexity of white-collar criminality in digital spaces and suggest that financial and demographic factors outweigh conventional criminological theories when predicting involvement in cryptocrime. Originality/value: This paper considers early notions of white-collar crime against modern online financial crimes. The authors addressed the intersection of criminological theory and modern cryptocurrency crime.
“Alexa, I’m home!” intimate surveillance, care, and control in AI-enabled homes and bodies
Brantly, Nataliya D. (Springer, 2026-04)
As artificial intelligence (AI) increasingly mediates everyday life, its expansion into intimate spaces produces new configurations of surveillance that blur the boundaries between care, necessity, and control. While smart home and digital health technologies are widely promoted as tools of safety and well-being, they embed pervasive forms of surveillance that remain underexamined. This paper analyzes how AI-enabled infrastructures govern intimate life through data extraction, algorithmic inference, and corporate control. Drawing on the combined theoretical lenses of surveillance capitalism and biopolitics, it conceptualizes smart homes and digital health systems as sites of marketized biopower, where corporate actors increasingly manage domestic routines and bodily processes. Using a structured critical-comparative analysis of two analytically complementary cases, the Ring Doorbell and the Dexcom continuous glucose monitor (CGM), the study traces how similar data logics operate across distinct domains of intimacy: domestic and bodily. The analysis demonstrates that, despite differences in function, regulation, and perceived necessity, both technologies centralize control under corporate infrastructures. In both cases, care operates as a governance strategy that legitimizes surveillance, normalizes dependency, and reframes autonomy as responsible participation in proprietary systems. The paper concludes by identifying ethical vulnerabilities and calling for AI governance frameworks attentive to intimacy, dependency, and predictive control, rather than privacy protections alone.
Corrosion Behavior of SS316H in Non-isothermal Fluoride Fuel Salt
Lee, Woohyuk; Leong, Amanda; Zhang, Jinsuo (TMS 2026, 2026-03-17)
This study investigates the impact of thermally driven mass transfer on the corrosion behavior of SS316H in molten NaF-BeF₂-UF₄-ZrF₄ salt using a static, non-isothermal system. A vertical temperature gradient from 717 °C (bottom) to 634 °C (top) was established over 6.5 inches without a forced salt circulation. SS316H samples were placed at heights of 0, 3, and 6.5 inches and exposed for 5, 10, and 15 days. Despite the absence of forced convection, significant mass transfer effects were observed. The hottest sample exhibited the greatest chromium depletion, while cooler regions showed less. Metallic deposition occurred on colder samples and in the surrounding salt, indicating directional transport driven by the thermal gradient. These results demonstrate that thermal gradients alone can induce notable corrosion-related mass transfer, challenging the conventional reliance on thermal convection loops. This highlights the need to consider temperature-driven mass transport in evaluating materials for molten salt reactor environments.
Metal redox control in molten NaF-BeF2-UF4-ZrF4 salt for corrosion mitigation
Lee, Woohyuk; Leong, Amanda; Park, Jaewoo; Zhang, Jinsuo (2024-10-11)
Sublethal Glyphosate Exposure Reduces Honey Bee Foraging and Alters Balance of Biogenic Amines in the Brain
McHenry, Laura C.; Schürch, Roger; Council-Troche, McAlister; Gross, Aaron D.; Johnson, Lindsay E.; Ohlinger, Bradley D.; Couvillon, Margaret J. (Company of Biologists, 2025-05-06)
Glyphosate is a broad-spectrum herbicide that inhibits the shikimate pathway, which honey bees (Apis mellifera), a non-target beneficial pollinator, do not endogenously express. Nonetheless, sublethal glyphosate exposure in honey bees has been correlated to impairments in gustation, learning, memory and navigation. While these impacted physiologies underpin honey bee foraging and recruitment, the effects of sublethal glyphosate exposure on these important behaviors remain unclear, and any proximate mechanism of action in the honey bee is poorly understood. We trained cohorts of honey bees from the same hives to forage at one of two artificial feeders offering 1 mol l⁻¹ sucrose solution, either unaltered (N=40) or containing glyphosate at 5 mg acid equivalent (a.e.) l⁻¹ (N=46). We then compared key foraging behaviors and, on a smaller subset of bees, recruitment behaviors. Next, we quantified protein levels of octopamine, tyramine and dopamine, and levels of the amino acid precursor tyrosine in the brains of experimental bees collected 3 days after the exposure. We found that glyphosate treatment bees reduced their foraging by 13.4% (P=0.022), and the brain content of tyramine was modulated by a crossover interaction between glyphosate treatment and the number of feeder visits (P=0.004). Levels of octopamine were significantly correlated with its precursors tyramine (P=0.011) and tyrosine (P=0.018) in glyphosate treatment bees, but not in control bees. Our findings emphasize the critical need to investigate impacts of the world’s most-applied herbicide and to elucidate its non-target mechanism of action in insects to create better-informed pollinator protection strategies.
WVEMS Protocols 2026: Protocols, Procedures, Policies & Medications of the Western VA EMS Medical Direction Committee
Stanley, Eric K. (2026-01-15)
Regional EMS Protocols for the WVEMS Council
Faith and Justice: Church Leadership's Impact on Prison Reform
Akowuah, Yaw Asamoah; Adusei, Frank Y.; Kaufman, Eric K.; Crowder, Loy V. (Stephen F. Austin ScholarWorks, 2026-04-03)
This study examines the Church of Pentecost’s (CoP) pioneering prison reform initiative in Ghana as a faith-based response to systemic overcrowding and inadequate rehabilitation infrastructure. Through a qualitative case study design, the research analyzes in-depth interviews with church leaders and media staff, alongside institutional documents, to explore how religious leadership intersects with correctional policy. Findings reveal that CoP’s “Vision 2023” strategy positioned prison decongestion as a moral and national imperative, leading to the construction of five “Inmates Skills Acquisition and Reformation Centres.” These facilities integrate vocational training, spiritual care, and modern infrastructure, aligning with Rehabilitation Theory’s emphasis on humane, reintegration-focused corrections. The project exemplifies transformational leadership, characterized by visionary commitment and ethical mobilization of resources. However, it encountered significant public and internal resistance due to communication gaps and the novelty of faith-based prison construction. The study contributes to scholarship on non-state actors in justice reform, demonstrating that religious organizations can drive structural change when grounded in theological mandates like missio Dei and imago Dei, yet underscores the critical need for proactive stakeholder engagement to ensure legitimacy and impact.
Epidemiological and Clinical Features of Drowning Cases in a Coastal Region of Türkiye: A Retrospective Study
Koyuncuoğlu, Halil Emre; Karakoyun, Ömer Faruk; Golcuk, Yalcin; Cantaş Türkiş, Fulden; Lareau, Stephanie (Emergency Medicine Association of Turkey, 2026-03-29)
Aim: Drowning is a critical public health issue and a leading cause of unintentional injury and death worldwide, particularly in coastal regions. This study aims to analyze the epidemiological trends, clinical features, and outcomes of drowning cases in Muğla Province, Türkiye, to guide targeted public health interventions and improve emergency care. Material and Methods: A retrospective, single-center observational study was conducted in a tertiary hospital’s emergency department from July 1, 2019, to July 1, 2024. Data from 45 patients diagnosed with drowning (ICD-10 code T75.1) were analyzed, including demographic characteristics, prehospital interventions, clinical severity scores, and outcomes. Statistical analyses were performed to evaluate predictors of 28-day mortality, with p<0.05 considered significant. Results: The median age of patients was 55 years (range: 3–83), with males comprising 53% of cases. Most incidents occurred in the summer (71.1%) and in the sea (93.3%). Abnormal electrocardiograms and radiological findings were strongly associated with mortality (p<0.001 and p=0.008, respectively). The Glasgow Coma Scale Score and Revised Trauma Score were the most accurate predictors of 28-day mortality, with an observed mortality rate of 15%. Comorbidities, including diabetes mellitus and coronary artery disease, also correlated with adverse outcomes. Conclusion: Drowning incidents remain a major challenge in coastal regions, necessitating enhanced prevention strategies, robust emergency resources, and validated scoring tools to improve patient outcomes. Future multicenter studies are needed to validate these findings and inform broader public health interventions.
Habitat suitability ensembles of genotype and disease resistance for Juglans cinerea to assist restoration efforts
Bascom, Carlisle S.; Conrad, Anna O.; Ebrahimi, Aziz; Jacobs, Douglass F.; Fearer, Carrie (Elsevier, 2026-07)
The environmental suitability of a particular organism is often a combination of local climatic factors, resource competition intensity, as well as pathogen and predator pressure. Pathogen pressure, or host resistance, is particularly important in host species severely impacted by disease. Variations in heritable pathogen resistance can lead to differences in apparent habitat suitability of resistant or susceptible subpopulations. In the case of the butternut tree (Juglans cinerea), habitat suitability is limited by genetic resistance to the non-native butternut canker disease (BCD) in addition to environmental factors. Further, butternut frequently crosses with the non-native, BCD-resistant, congenic Japanese walnut (Juglans ailantifolia) producing fertile hybrids. We sought to develop models of butternut or hybrid genotype and BCD resistance phenotypes that could inform conservation efforts. We combine two regression-based and three machine-learning based composite models to build a series of ensemble habitat suitability models of butternut and hybrid genotype, as well as butternut BCD resistance phenotype. Our ensembles highlight southern Indiana, western Kentucky, western Michigan, and much of New England as climatically suitable for BCD-resistant butternut. Meanwhile, much of the central Midwest and areas south of the Great Lakes are climatically suitable for hybrids. These ensembles can guide conservation efforts seeking to breed BCD-resistant butternut and hybrids by highlighting areas from which to source breeding stock or locate regeneration orchards.
Amonate: A Coal Camp Through Time (Part II – a comprehensive inventory)
Gilboy, Elizabeth; Gleason, Harry; Dupre, Karine; Kakkadan, Sneha; Muñoz-Vera, Gonzalo; Thomas, Jennifer; Tucker, Lisa; Rosier, Shaun; Ekberg, Caitlyn; McMahon, Carah; Dadd, Charlotte; Sincavage, Charlotte; Xiong, Jenny Xiqi; Meija, Ryan; Changani, Vaasav (Community Design Assistance Center, 2026-03-06)
This project documents the past and present of Amonate, Virginia - a former Faraday and Pocahontas Fuel Company coal camp - and identifies actionable pathways for preservation, community revitalization, and rural tourism. Led by a team from Virginia Tech in collaboration with Amonate Always, Inc., the work synthesizes historical research, field documentation, and community engagement into a comprehensive inventory and a set of near and long-term recommendations. The effort was supported through an interdisciplinary team and multiple grants. Beside key findings related to the historical significance and physical pattern of Amonate, this report presents deliverables and recommendations. As such, this study equips Amonate with the documentation, evidence, and early ideas needed to preserve its coal-camp heritage, build community capacity, and pursue incremental, feasible economic activity aligned with regional tourism patterns. The partnership among Amonate Always, CDAC/Virginia Tech, Mid-Atlantic TAB, and regional/state agencies provides a durable framework to convert momentum into sustained revitalization.
Virginia 4-H Volunteer Welcome Guide
Proudfoot, Chad (Virginia Cooperative Extension, 2026-03-20)
This guide is intended as a brief welcome and introduction to the Virginia 4-H program. It covers our history, our structure, your role, and the critical policies that ensure a safe and positive environment for all participants. Your local Virginia Cooperative Extension agent or 4-H staff members will provide more comprehensive information and training.
Informatics as a Well-Being Strategy
Uherick, Lisa; Waasdorp, C. J. (2026-03-17)
Comparison of cultural preferences and cultural practices in website design in Pakistan
Nizamani, Sehrish Basir; Nizamani, Saad; Basir, Nazish; Khoumbati, Khalil; Nizamani, Sarwat; Memon, Shahzad (Springer, 2025-11)
Purpose: Websites are typically influenced by the cultural context in which they are created and used. A website that is designed and used based on the preferences of its users and their culture is considered usable. Individuals’ cultural preferences refer to their level of cultural comfort, whereas cultural practices are shared perceptions of how people behave in a culture regularly as a whole. This article discusses the comparison of the web design preferences of users with the actual working practices of three categories of websites in Pakistan. Methods: The disparity between preferences and practices is examined utilizing Hofstede’s six cultural dimensions. Website design practices are collected through content analysis thematic coding is used to systematically categorize and analyze the data. Results: The results reflect that web design practices in Pakistan correspond to preferences in information density, information presentation, navigation, data restriction, error messages, content terminology, and gender roles. Mixed practices are observed in search results, cultural signs, colours, the purpose of images, menu choices, people’s images, user paths, the frequency of important links, input and feedback options and content density.
Nine changes needed to deliver a radical transformation in biodiversity measurement
Sutherland, William J.; Burgess, N. D.; Edwards, S. V.; Jones, J. P. G.; Soltis, P. S.; Tilman, D.; Allen, Julie M.; Andrianandrasana, H. T.; Armour, C. J.; August, T.; Bawa, K. S.; Bailey, S.; Birch, T.; Boersch-Supan, P. H.; Cavender-Bares, J.; Blaxter, M.; Chaplin-Kramer, R.; Daru, B. H.; De Palma, A.; Eisenberg, C.; Elphick, C. S.; Freckleton, R. P.; Frick, W. F.; Gonzalez, A.; Goetz, S. J.; Greenspoon, L.; Grozingeree, C. M.; Hankins, D. L.; Hazell, J.; Isaac, N. J. B.; Lambertini, M.; Lewin, H. A.; Aodha, O. M.; Madhavapeddy, A.; Milner-Gulland, E. J.; Milo, R.; O’Dwyer, J.; Purvis, A.; Salafsky, N.; Tallis, H.; Tanshi, I.; Vijay, V.; Wikelski, M.; Williams, D. R.; Woodard, S. H.; Robinson, G. E. (Proceedings of the National Academy of Sciences, 2026-03-10)
Biodiversity is declining in many parts of the world. Biological diversity measurement and monitoring are fundamental to the assessment of the causes and consequences of environmental changes, identification of key areas for the protection of biodiversity or ecosystem services, determining the effectiveness of actions, and the creation of decision-support tools critical to maintaining a sustainable planet. Biodiversity measurement is rapidly changing due to advances in citizen science, image recognition, acoustic monitoring, environmental DNA, genomics, remote sensing, and AI. In this perspective, we outline the exciting opportunities these developments offer but also consider the challenges. Our key recommendations are to 1) Capitalize on the ability of novel technology to integrate data sources 2) agree to standard methods for data collection 3) ensure new technologies are calibrated with existing data; 4) fill data gaps by using emerging technologies and increasing capacity, especially in the tropics; 5) create living safeguarded databases of trusted information to reduce the risk of poisoning by AI hallucinated, or false, information; 6) ensure data generation is valued; 7) ensure respectful incorporation of Indigenous Knowledge; 8) ensure measurements enable the quantification of effectiveness of actions, and 9) increase the resilience of global datasets to technical and societal change. Radical new collaborations are needed between computer scientists, engineers, molecular biologists, data scientists, field ecologists, citizen scientists, Indigenous peoples, policymakers, and local communities to create the rigorous, resilient, accessible biodiversity information systems required to underpin policies and practices that ensure the maintenance and restoration of ecological systems.
T-Type Labyrinth Seals Dynamic Response Evaluation Using Computational Analysis
Ashraf, Muhammad Mubashar; Untaroiu, Alexandrina (ASME International, 2026-03-06)
Effective sealing in rotating machinery is fundamental to maintaining efficiency and ensuring stable operation. Secondary leakage between high and low-pressure regions not only reduces performance but can also introduce destabilizing aerodynamic forces. Among annular gas seal technologies such as brush, hole-pattern, and honeycomb designs, labyrinth seals remain the most widely used because they are mechanically simple, reliable, and cost-effective. Recently, a modified T-type labyrinth seal has been introduced, demonstrating improved flow control and reduced flow-induced excitations compared to conventional straight-through configurations. The distinguishing feature of the T-type design is its T-shaped tooth geometry, which modifies the internal flow structure and enhances the inward radial forces associated with the Lomakin effect. This change in flow physics directly influences both leakage characteristics and rotordynamic behavior. Seal tip clearance plays a pivotal role. A smaller clearance generally reduces leakage but can alter aerodynamic stiffness and damping, thereby affecting rotor stability. Determining an appropriate clearance, therefore, requires more than a simple comparison at fixed geometry; it demands a structured parametric evaluation that captures the coupled aerodynamic and rotordynamic effects. Previous investigations have demonstrated leakage reductions of 23.6–25.3% for T-type labyrinth seals relative to straight-through designs, with axial length and tip clearance held constant. These findings point to clear performance advantages but leave open the question of optimal geometric tuning. Building on this, the present study conducts a sensitivity analysis using a design of experiments (DOE) framework coupled with steady-state computational fluid dynamics (CFD). The DOE approach enables systematic exploration of the clearance parameter space and quantifies the influence of the clearance parameter on leakage performance. In parallel, equivalent rotordynamic force coefficients are extracted from the CFD solutions to evaluate seal-induced stiffness and damping and to assess stability trends. To further establish practical relevance, the seal performance is examined across a range of pressure ratios and rotational speeds representative of aero-engine operating conditions. The results provide a coherent picture of how tip clearance governs both leakage and rotordynamic response in T-type labyrinth seals. Beyond confirming their leakage advantage, the study offers quantitative guidance for clearance selection and contributes to the broader effort to integrate aerodynamic performance and stability considerations into advanced seal design.
Assessments with Double Simultaneous Tactile Stimulation following Stroke: A Scoping Review Protocol
Paul, Arco; Holstege, Noah; Johnson, Caroline; Shalaby, Mei; Yau, Jeffrey; Chui, Kevin; Parcetich, Kevin; Comer, C. Cozette; Gurari, Netta (2026-03-24)
Intact somatosensory perception is essential to interact with our surrounding environment, including when performing basic daily tasks and learning skilled movements. Successful execution of voluntary movements depends on accurately processing and perceiving the incoming somatosensory information through integrated sensorimotor pathways. Somatosensory impairments following stroke are relatively common, affecting upwards of 85% of survivors living with stroke. Loss of tactile perception is among the most frequent occurring of the somatosensory impairments, impacting approximately 50% of these individuals in the USA. Common tactile impairments include hypoesthesia (reduced ability to feel touch), dysesthesia (abnormal tactile perception), and impaired two-point discrimination (reduced ability to discriminate between two nearby locations of touch). These impairments are often assessed using unilateral tactile stimulation on the more severely-affected (paretic) side, and, accordingly, do not capture more complex tactile impairments that can arise during bilateral interactions. One such impairment is tactile extinction (TE), a condition in which individuals can detect unilateral tactile stimuli on either side of the body but fail to perceive the same tactile stimuli on the paretic side when both sides are stimulated simultaneously. Most activities of daily living rely on coordinating touching and feeling of objects and using both upper extremities to manipulate them in a dynamic manner, such that both arms are stimulated. Tactile dysfunction that suppresses perception during such bilateral tasks can disrupt motor performance in daily activities and recovery. Therefore, understanding the nature of tactile dysfunction during bilateral tasks following stroke is valuable when considering how to effectively assess and, in turn, treat individuals. In this scoping review, we will explore approaches to assess tactile perceptual dysfunction during bilateral interactions post-stroke. Our aim is to summarize the current status of double simultaneous tactile stimulation approaches used for assessing tactile dysfunction. By considering the design of these approaches, we will identify need for further research, such as additional methods for assessment and implications of existing methods for interpreting why bilateral tactile dysfunction arises following stroke.
Investigating Toxicity of Bacteriophage Lambda N-Protein Upon Overexpression in Escherichia coli
Hite, Kristopher; Upton, Jan; Souders, Cole; Larson, Timothy J. (2026-03-09)
Over the course of two decades, cloning of a variety of native and engineered DNA fragments from bacteriophage lambda was performed as part of a capstone undergraduate course aimed at teaching fundamentals of recombinant DNA technology and regulation of gene expression in bacteria. Genomic DNA of bacteriophage lambda (λ–phage) was digested with BamHI and HindIII and the resulting DNA fragments were then ligated into similarly digested plasmid vector pUC19 to illustrate the principle of shot-gun cloning. E. coli strain TB1 was then transformed using selection for ampicillin resistance and the blue-white color screen. Upon analysis of recombinant plasmids isolated from white colonies, it became apparent that four of the five BamHI and HindIII DNA fragments were easily obtained, but one fragment was persistently missing. This 2396 bp BamHI-HindIII fragment between lambda phage genome coordinates 34500-36895 (Accession No. J02459.1) was dubbed the toxic fragment and contained the strong leftward promoter (pL) and downstream N gene encoding the transcription anti-terminator protein N, as well as the ‘rexA rexB genes. Truncation of this toxic fragment revealed that a smaller fragment (1,133 bp, spanning coordinates 34500-35632) was sufficient to confer toxicity upon cloning into pUC19. This smaller fragment contains the intact pL promoter, the open reading frame for the N-protein, and, importantly, 540 bp of 3’ untranslated DNA (UTR, which contains transcription terminator tL1). High level expression of the N-protein was hypothesized to be responsible for bacterial toxicity. This hypothesis was validated when the shorter (1,133 bp) toxic fragment was successfully transformed into strain TB1 containing pACλcI encoding lambda phage repressor protein which negatively controls expression of the N protein by binding to operators within the pL promoter. In addition, various mutations altering the pL promoter relieved toxicity. To further narrow the region of the UTR and/or N-protein responsible for bacterial toxicity, a series of truncations was created by PCR. Surprisingly, a recombinant plasmid containing the wild-type pL promoter and full length N-gene (but lacking tL1) was not toxic. Current research is focused on truncating and mutating bases within this 3’-UTR with the goal of understanding what role tL1 may be playing in toxicity

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