All Faculty Deposits

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https://hdl.handle.net/10919/70873

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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Now showing 1 - 20 of 6608

Cheesy Nights Stickers - Collaboration with student workers
Bengtson, Kelsey; Slowinski, Milana; Wedling, Morgan (2025-04-30)
Return of diversity: Wetland plant community recovery following purple loosestrife biocontrol
Endriss, Stacy B.; Nuzzo, Victoria; Blossey, Bernd (2025-06-07)
Spread of non-native species can be important drivers of biodiversity declines, leading to precautionary management based on assumptions that (1) non-native biota have negative impacts and are “guilty” of causing harm and (2) reducing a non-native species' abundance will reduce these negative impacts, in turn, benefiting native species. However, we frequently lack data to gauge both negative impacts of non-native species and success or failure of chosen management interventions to benefit native species. Addressing these knowledge gaps is critical to improving management outcomes for native species while maintaining public trust to sustain funding of management activities. Here, we investigated the response of Lythrum salicaria (purple loosestrife) and associated plant communities to implementation of biological control in more than 10 wetland sites in New York State for up to 28 years. Introduced to North America from Europe in the 1800s, L. salicaria is a prime example of a non-native species with a continent-wide distribution that could not be suppressed by mechanical and chemical treatments. In the 1980s, waterfowl biologists, wetland managers, and conservationists alike worried about the loss of diverse wetland plant communities associated with the rapid expansion of L. salicaria. In response, after careful assessments of safety, and potential costs and benefits, four highly host-specific insect herbivores were released in North America in the early 1990s to reduce L. salicaria abundance and its negative ecological impacts. In a companion paper, Blossey et al. documented reduced L. salicaria occupancy and stem densities following insect releases over time (i.e., biological success), irrespective of site-specific differences in starting plant communities or L. salicaria abundance. Here, we show that reduced abundance of L. salicaria leads to the ultimate goal of non-native plant management: increased cover, abundance, and diversity of species, often of native species (i.e., ecological success). We also conduct analyses to provide inference about which plant species are most sensitive to L. salicaria, including changes in L. salicaria stem density. Overall, we provide an important conservation success story: our findings emphasize that biocontrol of non-native plants can be effective and safe, allowing native species to recover as a dominant non-native species gradually declines.
Elements of Leadership: Considerations for "Citizenship"
Kaufman, Eric K. (2025-06-07)
Opening seminar for 2025 TYIL Fellowship Program, an an initiative of the Teens and Youths in Leadership (TYIL) in Nigeria.
Insights into the in-situ degradation and fragmentation of macroplastics in a low-order riverine system
Gray, Austin D.; Gore, Beija; Gaesser, Megan; Sequeira, Luisana Rodriguez; Thibodeau, Tessa; Montgomery, Allison; Purvis, Sam; Ouimet, Kathryn; Dura, Tina; Mayer, Kathleen (Oxford University Press, 2025-05)
Inland riverine systems are major conduits of microplastics to coastal environments. Plastic materials that pass through riverine systems are subjected to various degradation processes that facilitate their fragmentation into microplastics (MPs). Low-order streams, a critical yet understudied part of river networks, significantly influence the fate and transport of MPs. Here, we investigate the in situ degradation of common macroplastic polymers (e.g., low-density polyethylene, polyethylene terephthalate, and polystyrene) and their fragmentation into MPs in urban and forested streams. We deployed macroplastic items and a natural biodegradable polymer (cellulose) into a stream habitat for 52 weeks. We found that regardless of stream type (forested or urban), macroplastic polymers produced MPs in two weeks, with polystyrene having the highest fragmentation rate (8 particles/week). We explored several degradation indices (carboxyl index, hydroxyl index, and vinyl index), which revealed that photooxidation played a role in macroplastic degradation over time. Another driver of degradation was biofilm formation observed on the surface of all items, mainly composed of diatoms. Lastly, we found that field-aged macroplastics can leach plastic-derived dissolved organic. Our study narrows the knowledge gap regarding MP degradation and fragmentation in freshwater by providing real-time in situ data on the rate of polymer fragmentation in a low-order riverine system.
Pre-conference professional workshop on Evalpreneurship in Africa
This interactive full-day workshop facilitated by Nicolas Uwitonze (Rwandan, who is currently pursuing a Ph.D. at Virginia Tech with a focus on Evalpreneurship and KAI), aims to delve into the intricate intersection of evaluation, consulting, entrepreneurship, and equity in the African context amid the digital age. Participants, ranging from intermediate to advanced, will actively engage in discussions and collaborative activities, gaining a holistic understanding of Evalpreneurship as a socially constructed phenomenon. The agenda includes an introduction to Evalpreneurship, exploration of global and African case studies, distinguishing evaluation entrepreneurship from consultancy, and discussions on the impact of technology and emerging trends in African evaluation entrepreneurship. The workshop will also feature an interactive session, allowing participants to explore challenges and opportunities in African Evalpreneurship through small group discussions and participant-led scenarios. The session concludes with an open forum for questions, reflections, and insights. Learner outcomes include gaining insights into holistic Evalpreneurship, exploring real-world applications and equity considerations, distinguishing evaluation entrepreneurship from consultancy, understanding the impact of technology on African evaluation entrepreneurship, and navigating complexities in participatory approaches. No certificates of participation will be provided, and the ideal number of participants is set at 12, with a maximum of 40. Course materials will consist of handouts, case studies, and access to relevant online resources. The workshop will be conducted in English, with simultaneous translation into French/Kinyarwanda available upon request. Young and emerging evaluators are mostly invited, as well as intermediate to Advanced participants with an interest in evaluation, consulting and entrepreneurship. Justification/Relevance to the theme. The proposed workshop not only aligns with the conference theme but also directly addresses each of its objectives, by: 1) Advancing the Evaluation Agenda with Evidence-Based Policy Formulation: The workshop addresses the evolving landscape of evaluation practices by incorporating technology and innovation. It delves into the intricate intersection of evaluation, consulting, entrepreneurship, and equity in the African context, acknowledging the transformative impact of technology. The insights gained from the workshop empower participants to contribute meaningfully to evidence-based policy formulation, aligning with the conference's goal of strengthening Voluntary Organizations for Professional Evaluation (VOPEs) to collaborate with national governments. 2) Enhancing National Evaluation Capacities through Shared Experiences: The workshop provides a platform for participants to actively engage in discussions, collaborative activities, and real-world case studies. This interactive approach fosters a shared learning experience, enabling participants to explore challenges, opportunities, and lived experiences in the field of evaluation entrepreneurship. This aligns with the conference's objective of providing space for sharing experiences to enhance national evaluation capacities. 3) Showcasing Evaluative Evidence in Africa: By exploring real-world applications and equity considerations in Evalpreneurship, the workshop contributes to showcasing the diverse ways evaluative evidence can be leveraged for social impact. The insights gained from case studies and discussions offer tangible examples of how evaluation, entrepreneurship, and technology intersect in the African context, thereby contributing to the conference's goal of showcasing the use of evaluative evidence in Africa. 4) Development of Young and Emerging Evaluators: The workshop specifically targets young and emerging evaluators, providing them with practical knowledge and skills to navigate the evolving landscape of Evalpreneurship. By actively engaging this demographic, the workshop contributes directly to the conference's aim of developing young and emerging evaluators as agents of change. It empowers them to understand the complexities of the digital age and fosters their role as catalysts in the evaluation field.
Evalpreneurship in Africa: Exploring the Landscape of Supply and Demand
Uwitonze, Nicolas (African Evaluation Association (AfrEA), 2024-03-20)
In recent decades, the role of evaluation in shaping African development strategies has undergone a significant transformation, emerging as a powerful tool for evidence-based decision-making, accountability, and learning. Concurrently, Africa's dynamic entrepreneurial landscape, guided by innovation hubs and a resilient informal sector, plays a pivotal role in tackling challenges like unemployment and poverty while fostering robust economic growth. Despite recognizing the vital roles of evaluation and entrepreneurship, their intersection remains largely unexplored in scholarly discourse. Exploring this intersection yields insights into the intricate integration of entrepreneurial practices into evaluation work, as evidenced by Sabarre's groundbreaking study on "evalpreneurship in the USA" (2021). Building on Lemire, Nielsen, and Christie's foundational work (2018), Sabarre's research delves into the structural aspects of the evaluation marketplace, particularly the influence exerted by evaluation entrepreneurs. However, these discussions predominantly focus on the global north, necessitating a similar scrutiny in the African context. This paper aims to bridge this gap by contributing to the existing literature. It investigates the supply and demand landscape of the African evaluation marketplace. Using a literature review methodology, the paper draws on diverse sources, including research articles, policy documents, and reports spanning two decades. Employing the "emergent evaluation market framework" as a structured lens, the study provides insights into buyer-seller interactions and the exchange of evaluation services within Africa, as demonstrated in studies by Lemire et al. (2018). The findings illuminate the current and historical context of evaluation commissioning in Africa, emphasizing the roles and contributions of key players in the supply chain. Additionally, the paper explores external factors acting as enablers or barriers to the influence of entrepreneurs on the supply and demand of evaluations in Africa. The research underscores the transformative potential of evalpreneurship in driving the decolonization of evaluation and dismantling white supremacy in the continent's development. In advocating for contextually relevant, culturally responsive, and Made in Africa evaluation practices, the paper calls for further research on Africa-based evaluation entrepreneurs to understand their evolving roles in shaping evaluation supply and demand
Digital Preservation Landscape: Updates & Observations
Kinnaman, Alex (2025-05-30)
A high-level overview of the digital preservation landscape investigating vendor service providers competing with community service providers, recent and upcoming sunsets of community-based digital preservation organizations, and evaluation of how APTrust compares to recent shifts in the landscape.
How Do We Retain and Promote Followership Scholarship and Discourse? Opportunities with a Digital Followership Collection
Oyedare, Israel; Kaufman, Eric K. (2025-05-29)
While followership research is increasingly becoming popular, its literature is thinly dispersed, making it difficult to find. Thus, Virginia Tech, through a mini-grant and two years of research, is building a digital followership collection with the goal of supporting and advancing the field. This session will introduce participants to the platform, share its potential benefits across contexts, and demonstrate the prospect of artificial intelligence for sustaining the field of followership.
Everyday Followership: How We Lead by Following in Life’s Most Personal Arenas
Kaufman, Eric K. (2025-05-30)
Followership is often framed in workplace and organizational contexts, but its impact extends far beyond professional settings. This facilitated session explores followership in deeply personal aspects of life, including healthcare, fitness, religion, and civic engagement. Participants will engage in discussions about how individuals navigate power, responsibility, and decision-making as followers in these areas. The session will examine how effective followership contributes to well-being, ethical decision-making, and social cohesion. Through interactive exercises and shared experiences, attendees will identify strategies for enhancing their followership in ways that support personal growth and community development.
The Power of Storytelling: Creatively Facilitating Conceptual Change in the Classroom
Rose, Mackenzie S.; Johnson, Marcus (2025-05)
Conceptual knowledge encompasses understanding the interrelationships among multiple pieces of information. Misconceptions of these interrelationships illustrate the need for effective educational strategies to facilitate conceptual change, with the goal of facilitating changes in learner understanding to appropriate, accurate, and complete concepts. Strategies, such as refutation texts, have proven effective in addressing science misconceptions, yet there is a prominent gap in research on conceptual change in nonscience subjects and the use of storytelling to facilitate such change. Storytelling, presented in a range of educational subjects, invites learners to engage in social discourses and problem-solving exercises. Prompted by classroom storytelling practices, creativity, flexibility, and high levels of motivation support learners in approaching ambiguous or complex instructional material as well as promote abstract conceptualization. Despite storytelling’s oral tradition, diverse formats using technology and digital platforms position storytelling as a multidimensional, multidisciplinary pedagogical strategy for conceptual change.
Using musculoskeletal models to estimate the effects of exoskeletons on spine loads during dynamic lifting tasks: differences between OpenSim and the AnyBody modelling system
Behjati Ashtiani, Mohamad; Akhavanfar, Mohammadhossein; Li, Lingyu; Kim, Sunwook; Nussbaum, Maury A. (Elsevier, 2025-05-23)
Occupational back-support exoskeletons (BSEs) can reduce physical demands during lifting by providing assistive torques, but their effects on spine loading are poorly understood. In this study, we used two common musculoskeletal models developed in OpenSim and the AnyBody Modeling System to estimate intervertebral joint forces (IJF) during asymmetric and symmetric lifting tasks with and without BSEs. Data from an earlier study were used, involving 18 participants who performed repetitive lowering/lifting in three task conditions and with three different BSEs (along with a control condition using no BSE). We simulated the tasks with both models and estimated axial compression and anteroposterior shear forces at the L4/L5 joint and derived peak values (95th percentile) as outcome measures. OpenSim estimated significantly larger axial compression and anteroposterior shear forces than AMS. Both models estimated reductions in spine loading when using either of the BSEs, though OpenSim estimated greater reductions than AMS. Strong positive, linear relationships (r > 0.95) between the two model estimates were found for axial compression, while much weaker and even negative relationships were observed for shear forces, especially under asymmetric conditions. The differences in model estimates were likely due to variations in model assumptions and passive tissue representations. Future research should explore more detailed human-exoskeleton interaction models, evaluate the impact of modelling assumptions on IJF estimates, and assess the agreement of these findings with in vivo measurements such as electromyography.
Effectiveness and usability of a trunk posture feedback system: An exploratory, longitudinal study for up to 10 days among vehicle assembly operators
Choi, Jiwon; Kim, Sunwook; Lim, Sol; Porto, Ryan; Nussbaum, Maury A. (Elsevier, 2025-10)
Postural feedback systems are a potential ergonomic intervention to reduce postural exposures, and thus musculoskeletal disorder risk, but field-based evidence of their longer-term effectiveness remains limited. We conducted an exploratory investigation of a commercial postural feedback system, which provided auditory and vibrotactile feedback following excessive trunk motion, in vehicle manufacturing. Eight workers used the system during regular shifts for up to 10 workdays. We observed a reduction in “poor” postures on the first day of feedback. However, these benefits diminished over time, possibly due to a novelty effect—with improvements diminishing as participants adapted to the system—and effects varied greatly across participants. Participant responses were mixed; some reported improved postural awareness while others found the feedback irritating and often ignored it. Findings from this exploratory study suggest the importance of enhancing postural feedback system design to sustain behavioral change over time and better support individual needs.
Cytoplasmic connexin43-microtubule interactions promote glioblastoma stem-like cell maintenance and tumorigenicity
Smyth, James W.; Guo, Sujuan; Chaunsali, Lata; O’Rourke, Laurie; Dahlka, Jacob; Deaver, Stacie; Lunski, Michael; Nurmemmedov, Elmar; Sontheimer, Harald; Sheng, Zhi; Gourdie, Robert G.; Lamouille, Samy (Springer, 2025-05-16)
Glioblastoma (GBM) is the most common primary tumor of the central nervous system. One major challenge in GBM treatment is the resistance to chemotherapy and radiotherapy observed in subpopulations of cancer cells, including GBM stem-like cells (GSCs). These cells have the capacity to self-renew and differentiate and as such, GSCs participate in tumor recurrence following treatment. The gap junction protein connexin43 (Cx43) has complex roles in oncogenesis and we have previously demonstrated an association between Cx43 and GBM chemotherapy resistance. Here, we report, for the first time, increased direct interaction between non-junctional Cx43 and microtubules in the cytoplasm of GSCs. We hypothesize that non-junctional Cx43/microtubule complexing is critical for GSC maintenance and survival and sought to specifically disrupt this interaction while maintaining other Cx43 functions, such as gap junction formation. Using a Cx43 mimetic peptide of the carboxyl terminal tubulin-binding domain of Cx43 (JM2), we successfully disrupted Cx43 interaction with microtubules in GSCs. Importantly, administration of JM2 significantly decreased GSC survival in vitro, and limited GSC-derived and GBM patient-derived xenograft tumor growth in vivo. Together, these results identify JM2 as a novel peptide drug to ablate GSCs in GBM treatment.
Advancing Agrivoltaics in Virginia
White, Robin R.; Hall, Ralph P.; Ignosh, John; Fike, John H.; Nguyen, Nam (Virginia Tech. College of Agriculture and Life Sciences, 2025-05-05)
Summit Motivation, Background, and Purpose: The motivation for the 2024 agrivoltaics summit stemmed from Virginia's growing need to balance the conservation of agricultural land with the rapid expansion of renewable energy, particularly solar power. As land-use conflicts, economic pressures on rural communities, and the need for climate resilience intensify, agrivoltaics offers a promising solution by enabling the dual-use of land for both farming and solar energy production. The agrivoltaics summit aimed to define strategies for collaboration between industry and state agencies to support agrivoltaics during the renewable energy transition, explore opportunities and challenges from diverse perspectives, and establish a network dedicated to evaluating and advancing agrivoltaics opportunities relevant to Virginia stakeholders.
Two Novel Slip Training Methods Improve the Likelihood of Recovering Balance After a Laboratory-Induced Slip
Allin, Leigh J.; Nussbaum, Maury A.; Madigan, Michael L. (Human Kinetics, 2018-08-06)
Task-specific balance training is an approach to fall prevention that has the potential to reduce the number of slip-induced falls. However, a limitation of current task-specific training methods is that they require nontrivial financial and/or equipment resources. This pilot study evaluated the efficacy of 2 low-cost, low-tech methods for slip-recovery training in improving balance recovery ability. The 2 methods were as follows: (1) repeated unexpected slip training (UST), which involved repeated unexpected slips while walking (similar to current methods of task-specific slip-recovery training) and (2) volitional sliprecovery training (VST), which involved practicing a slip recovery response after volitionally stepping to induce a slip-like perturbation. A total of 36 young adults completed 1 training session (UST, VST, or control), followed by 1 unexpected, laboratory-induced slip while walking on the following day. Compared with controls, UST and VST resulted in a higher proportion of successful balance recoveries from the laboratory-induced slips. UST improved both proactive control and the reactive stepping response after slipping, whereas VST improved the ability to arrest the motion of the slipping foot. Based on these preliminary results, UST and VST may provide practical, cost-effective methods for slip-recovery training.
Required friction during overground walking is lower among obese compared to non-obese older men, but does not differ with obesity among women
Arena, Sara L.; Garman, Christina R.; Nussbaum, Maury A.; Madigan, Michael L. (Elsevier, 2017-02-27)
Obesity and aging have been independently associated with altered required friction during walking, but it is unclear how these factors interact to influence the likelihood of slipping. Therefore, the purpose of this study was to determine whether there are differences related to obesity and aging on required friction during overground walking. Fourteen older non-obese, 11 older obese, 20 younger non-obese, and 20 younger obese adults completed walking trials at both a self-selected and hurried speed. When walking at a hurried speed, older obese men walked at a slower gait speed and exhibited lower frictional demands compared both to older non-obese men and to younger obese men. No differences in required friction were found between non-obese and obese younger adults. These results suggest that the increased rate of falls among obese or older adults is not likely due to a higher risk of slip initiation.
ROPES Hub Research Brief: Understanding Curricular Complexity for Engineering Transfer Students
Grote, Dustin; Knight, David B.; Richardson, Amy Jo (2025-05-28)
Relative Effort while Walking Is Higher among Women Who Are Obese, and Older Women
Koushyar, Hoda; Anderson, Dennis E.; Nussbaum, Maury A.; Madigan, Michael L. (Lippincott Williams & Wilkins, 2019-07-23)
Purpose: Individuals who are obese, and older individuals, exhibit gait alterations that may result, in part, from walking with greater effort relative to their maximum strength capacity. The goal of this study was to investigate obesity-related and age-related differences in relative effort during gait. Methods: Four groups of women completed the study, including 10 younger healthy-weight, 10 younger obese, 10 older healthy-weight, and 9 older obese women. The protocol included strength measurements at the hip, knee, and ankle in both flexion and extension, and gait trials under self-selected and constrained (1.5 m·s-1 gait speed and 0.65-m step length) conditions. Relative effort was calculated as the ratio of joint torques during gait, and strength from a subject-specific model that predicted strength as a function of joint angle. Results: Relative effort during self-selected gait was higher among women who were obese in knee extension (P = 0.028) and ankle plantar flexion (P = 0.013). Although both joint torques and strength were higher among women who were obese, these increases in relative effort were attributed to greater obesity-related increases in joint torques than strength. Relative effort was also higher among older women in hip flexion (P < 0.001) and knee extension (P = 0.008), and attributed to age-related strength loss. Results were generally similar between self-selected and constrained gait, indicating the greater relative effort among women who were obese and older women was not attributed to differences in gait spatiotemporal characteristics. Conclusions: Women who were obese, as well as older women, walk with greater relative effort. These results may help explain the compromised walking ability among these individuals.
Obesity as a Factor Contributing to Falls by Older Adults
Madigan, Michael L.; Rosenblatt, Noah J.; Grabiner, Mark D. (Springer, 2014-05-24)
The growth of the worldwide population of older adults presents significant challenges, many inter-related, that range from the health of individuals to the health of national economies. In the US, more than one-third of older adults may be obese, a condition that may independently increase the risk for mobility impairment, fall-related injury and, possibly, costs of post-injury treatment and care. The effectiveness of conventional exercise-based fall prevention programs is significant but smaller than both the annual rate of falling of older adults and rate of growth of this population, who are at greatest risk for injurious falls. The anthropometric and functional consequences of obesity may impose limitations on the ability to perform compensatory stepping responses following large postural disturbances. The focus of this paper is the potential of task-specific training to improve compensatory stepping responses and reduce falls by obese people given the individual-specific anthropometric and functional consequences of obesity.
Impaired plantar sensitivity among the obese is associated with increased postural sway
Wu, Xuefang; Madigan, Michael L. (Elsevier, 2014-09-19)
Impaired foot plantar sensitivity has been hypothesized among individuals who are obese, and may contribute to their impaired balanced during quiet standing. The objective of this study was to investigate the effects of obesity on plantar sensitivity, and explore the relationship between plantar sensitivity and balance during quiet standing. Thirty-nine young adults from the university population participated in the study including 19 obese and 20 non-obese adults. Plantar sensitivity was measured as the force threshold at which an increasing force applied to the plantar surface of the foot was first perceived, and the force threshold at which a decreasing force was last perceived. Measurements were obtained while standing, and at two locations on the plantar surface of the dominant foot. Postural sway during quiet standing was then measured under three different sensory conditions. Results indicated less sensitive plantar sensitivity and increased postural sway among the obese, and statistically significant correlations between plantar sensitivity and postural sway that were characterized as weak to moderate in strength. As such, impaired plantar sensitivity among individuals who are obese may be a mechanism by which obesity degrades standing balance among these individuals.

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