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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Suitability of paddy cultivation in the Western province of Sri Lanka under different climate change scenarios
Pitawala, Kasuni G.; Vidanage, Shamen P.; Mutuwatte, Lal P.; Alotaibi, Bader Alhafi; Najim, M. M. M.; Nayak, Roshan K. (Public Library of Science, 2025-10-27)
Climate change poses a significant threat to global agriculture, with implications for food security. Regions that rely heavily on rain-fed agriculture, especially in developing countries, such as the Western province of Sri Lanka are particularly vulnerable. The current research aims to assess future climate expectations and their impacts on paddy cultivation in Sri Lanka's Western province for the purpose of identifying measures to address the multi-faceted consequences of climate change. The main objective of the study was to determine the spatial suitability of paddy in the Western province for the years 2030 and 2050 under different climate change scenarios. Rice occurrence points and bioclimatic variables were employed to model the spatial suitability of paddy under current, 2030 SSP 245, 2030 SSP 585, 2050 SSP 245, and 2050 SSP 585 climatic conditions using 'biomod2' package of RStudio software. The results revealed that areas unsuitable for paddy cultivation increased under 2030 SSP 245 (1,437.30 km2), 2030 SSP 585 (1,594.80 km2), 2050 SSP 245 (2,624.40 km2), and 2050 SSP 585 (2,627.10 km2) conditions when compared with current (1,044 km2) climatic conditions. Further, the simulation indicated that the species range change between the current climatic conditions and 2030 SSP 245 (-16.58), 2030 SSP 585 (-13.62), 2050 SSP 245 (-37.03), and 2050 SSP 585 (-50.51) is negative. The percentage loss in paddy range between current and 2030 SSP 245, 2030 SSP 585, 2050 SSP 245 and 2050 SSP 585 climatic conditions were shown to be 52.94%, 47.89%, 22.07% and 67.85%, respectively. Therefore, the results of the present study highlight the need for a comprehensive approach that integrates climate change adaptation and mitigation in agriculture to ensure food security and to protect vital ecosystems. The findings of this study can be utilized by researchers, policymakers, and practitioners aiming to achieve global sustainability goals.
Redefining Perceived Boundaries: Insights into the Audit Committee's Evolving Responsibilities
Cunningham, Lauren M.; Stein, Sarah E.; Walker, Kimberly; Wolfe, Karneisha (American Accounting Association, 2025-07)
Oversight responsibilities for many audit committees (ACs) are evolving to include some of the hottest topics in the boardroom: enterprise risk management, cybersecurity, and environmental, social, and governance reporting. However, certain ACs avoid overseeing these evolving areas, creating significant variation across boards in the assignment of responsibilities. In this study, we seek to understand how ACs respond when environmental changes create new evolving risks that may extend the boundary of their traditional domain. To do so, we interview a diverse set of 29 AC members from U.S. publicly traded companies. We analyze our data through the theoretical lens of collaborative boundary work to identify how ACs respond by extending, blurring, or maintaining their perceived oversight boundaries, the related implications of these decisions, and their key tactics employed to manage AC workload. Our findings should be of interest to boards, investors, and regulators tasked with monitoring AC effectiveness.
Imitation without Intention: A Qualitative Analysis of Isomorphic Audit Committee Disclosures
Cunningham, Lauren M.; Stein, Sarah E.; Walker, Kimberly; Wolfe, Karneisha (2025-04-29)
Audit committee (AC) oversight is critical for maintaining investors’ confidence in financial reporting as well as other areas of expanded AC responsibility. However, it is unclear to what extent investors can meaningfully evaluate AC oversight quality based on public disclosures. We observe that some companies stay firmly rooted in disclosures that comply with minimal regulatory standards, while others voluntarily expand disclosures to discuss industry-recommended information primarily related to financial reporting and audit oversight. Rarely do we observe companies expanding their disclosures past industry recommendations to provide company-specific context that outlines AC member qualifications, training, and temporal changes in risk oversight. To explore how companies decide on the extent of AC disclosures and how well they address investor needs, we conduct semi-structured interviews with 30 AC members, five disclosure preparers, and 14 members of the investment community. We find the current disclosure process creates a disproportionate focus on standardized language—aligning with coercive and mimetic isomorphism—that fails to provide investors with sufficient information to distinguish AC oversight quality across companies. We further observe that ACs may be willing to expand disclosures to signal their oversight activities if they receive direct investor feedback about the usefulness of such disclosures. However, limited channels for direct investor-to-company feedback, combined with investors’ perception that current disclosures do not provide enough information to engage, often result in investors’ silence. This silence leads companies to incorrectly assume that investors are satisfied with current disclosures. We conclude with suggestions for closing this legitimacy gap, along with examples of potential disclosure enhancements.
A Broken Heart: Grief-Associated Left Ventricular Rupture with Non-Occlusive Coronary Arteries
Ward, Maxwell; Wu, K.; Ayzenbart, Vira I.; Mirza, Mohd A.; Kietrsunthorn, Patrick S. (2025-09-05)
Ischemic Events Occur Early in Patients Undergoing Percutaneous Coronary Intervention and Are Reduced With Cangrelor: Findings From CHAMPION PHOENIX
Cavender, Matthew A.; Harrington, Robert A.; Stone, Gregg W.; Steg, Gabriel; Gibson, C. Michael; Hamm, Christian W.; Price, Matthew J.; Lopes, Renato D.; Leonardi, Sergio; Deliargyris, Efthymios N.; Prats, Jayne; Mahaffey, Kenneth W.; White, Harvey D.; Bhatt, Deepak L.; CHAMPION PHOENIX Investigators (Wolters Kluwer Health, 2022-01)
Background: Thrombotic events are reduced with cangrelor, an intravenous P2Y₁₂ inhibitor. We sought to characterize the timing, number, and type of early events (within 2 hours of randomization) in CHAMPION PHOENIX (A Clinical Trial Comparing Cangrelor to Clopidogrel Standard of Care Therapy in Subjects Who Require Percutaneous Coronary Intervention). Methods: CHAMPION PHOENIX was a double-blind, placebo-controlled trial that randomized patients undergoing percutaneous coronary intervention to cangrelor or clopidogrel. For this analysis, we evaluated the efficacy of cangrelor in the first 2 hours postrandomization with regards to the primary end point (death, myocardial infarction, ischemia-driven revascularization, or stent thrombosis). Sensitivity analyses were performed evaluating a secondary, post hoc end point (death, Society of Coronary Angiography and Intervention myocardial infarction, ischemia-driven revascularization, or Academic Research Consortium definite stent thrombosis). Results: The majority of events (63%) that occurred in the trial occurred within 2 hours of randomization. The most common early event was myocardial infarction; next were stent thrombosis, ischemia driven revascularization, and death. In the first 2 hours after randomization, cangrelor significantly decreased the primary composite end point compared with clopidogrel (4.1% versus 5.4%; hazard ratio, 0.76 [95% CI, 0.64-0.90], P=0.002). Similar findings were seen for the composite end point of death, Society of Coronary Angiography and Intervention myocardial infarction, ischemia-driven revascularization, or Academic Research Consortium stent thrombosis at 2 hours (0.9% versus 1.6%; hazard ratio, 0.57 [95% CI, 0.40-0.80], P=0.001). Between 2 and 48 hours, there was no difference in the primary composite end point (0.6% versus 0.5%; odds ratio, 1.17 [95% CI, 0.71-1.93]; P=0.53). Early (≤2 hours of randomization) GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) moderate or severe bleeding events were infrequent, and there was no significant difference with cangrelor compared with clopidogrel (0.2% [n=10] versus 0.1% [n=4]; adjusted odds ratio, 1.41 [95% CI, 0.37-5.40]; P=0.62). Conclusions: The reductions in ischemic events and overall efficacy seen with cangrelor in CHAMPION PHOENIX occurred early and during the period of time in which patients were being actively treated with cangrelor. These findings provide evidence that supports the importance of potent platelet inhibition during percutaneous coronary intervention. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01156571.
Spray-coated polylactic acid/polyhydroxyalkanoate biodegradable bioplastic films on paper: A sustainable strategy for enhancing barrier and mechanical properties
Cao, Chenxi; Ahn, Kihyeon; Hong, Su Jung; Kim, Young-Teck; He, Zunhuang; Huang, Haibo; Wang, Zhiwu; Lee, Eunhye; Shim, Yookyoung (Elsevier, 2026-01)
This study proposes a sustainable alternative to conventional plastic coatings in packaging by developing a biodegradable coating system based on polylactic acid (PLA) and polyhydroxyalkanoate (PHA). A novel spray coating technique followed by hot pressing was used to apply PLA/PHA blends onto kraft pulp paper. This approach aimed to enhance mechanical strength, barrier properties, and water resistance while maintaining compostability. The coating behavior was strongly influenced by the PLA to PHA ratio. PLA formed a dense surface layer that effectively sealed pores, while PHA penetrated more deeply into the fibrous matrix, filling internal voids. These complementary roles contributed differently to the mechanical and barrier properties. In particular, the 50:50 PLA/PHA blend showed the most balanced results, achieving the lowest oxygen transmission rate and improved tensile strength. The thermogravimetric analysis further confirmed enhanced thermal stability in all coated samples compared to uncoated paper, with the degradation temperature profile shifting depending on the polymer composition. However, coatings with excessive PHA content showed surface irregularities and reduced barrier performance due to poor film formation. Overall, this work demonstrates that compositional tuning of PLA and PHA enables multifunctional coatings with improved mechanical, thermal, and barrier properties. The proposed spray-based method offers a scalable, eco-friendly solution for high-performance biodegradable packaging.
State-of-the-industry of anchorage zone design for pretensioned bulb-tee bridge girders
Brouwer, Heather; Carnes, Thomas S.; Jacques, Eric; Roberts-Wollmann, Carin L. (Virginia Tech, 2023-12)
The purpose of this project is to develop an improved prestressed concrete anchorage zone detail that mitigates end-zone cracking and reduces the congestion of reinforcement in the anchorage zone for VDOT. The current detail provides an adequate level of crack control, but it generally requires a very large amount of steel. This project is considering solutions such as added horizontal reinforcement in the form of WWR, splayed draping, and debonding. The purpose of this report is to provide background information on the current state of the industry and recent research to inform the analysis of the possible solutions. The project team performed a literature review, surveyed departments of transportation nationwide, and visited five precast plants in Virginia and surrounding states. The results of these investigations will be used in the development of a parametric finite-element study to determine the optimal configuration of possible solutions. The literature review includes current design methods used in practice, published design methods from research, and investigation of the influence of different factors on design performance. The AASHTO and VDOT design approaches for mild crack control reinforcement were presented. Four design methods for mild steel in the anchorage zone found in literature were discussed including empirical design, cracked equilibrium, strut-and-tie model, and shear transfer design approaches. Six factors affecting the performance of anchorage zones have been studied in prior research including debonding. Additional research into modified prestressing arrangements and the addition of horizontal steel, particularly WWR, should be considered. A survey was sent out in May 2023 to determine the detailing and repair practices of different DOTs for prestressed concrete bulb-tee girders. From the responses of 34 DOTs, it was found that most states allow the use of prestressed concrete bulb-tee girders. Many states modify AASHTO provisions for anchorage zones based on their own research and experience. Many also have their own typical details that vary from AASHTO’s prescriptions. In terms of repair practices, most states did not have consistent crack widths to trigger different repairs. Five precast plants in Virginia and surrounding areas were toured and stock beams were examined for end zone cracking. The observed beams had a wide variety of end zone cracking severities, but some states’ details were more prone to cracking than others. Pennsylvania details tended to perform very well relative to other states, and Maryland design details performed poorly. Most other state details performance fell between Pennsylvania and Maryland. A cursory analysis of the data collected from beams at the precast plants was performed to identify key factor interactions. One significant relationship identified was between the prestress force, the depth of the beam, the transfer length and net crack width. This trend showed a positive correlation in net cracking with level of prestress and depth of the section. Many other combinations of factors were compared, but none yielded a clear correlation. Further analysis through statistics and strut-and-tie modeling is recommended.
Decentralised drinking water regulation: Risks, benefits and the hunt for equality in the Canadian context
Calder, Ryan S. D.; Schmitt, Ketra A. (Inderscience Publishers, 2015-07-29)
Drinking water management in Canada is based on the intervention of provinces and territories. This contrasts with the American and European approach of uniform, legally enforced regulation at the federal or super-federal level. The Canadian model has been widely criticised for the unequal level of regulation between provinces and territories and the passive role taken by the federal government. This paper: 1) puts calls for greater centralisation in the context of Canada's social and political climate; 2) reviews government, academic and environmental advocacy literature on competing drinking water regulation paradigms; 3) evaluates strengths and weaknesses of centralised and decentralised frameworks for drinking water regulation in the context of risk management theory and practical challenges. Notably, we evaluate drinking water decision-making as one of many competing opportunities for public spending on risk abatement and posit that increasing the uniformity of drinking water quality does not necessarily increase overall equality.
Raising each other up through sustainable, community-building professional development
Hammer, Kelsey; Comer, C. Cozette; MacDonald, Amanda B.; McNabb, Kayla B.; Russell, Lisa Becksford (2025-10-03)
Participants will learn how a university library developed communities of practice (CoP) over time into a sustainable collaboration fostering transformative growth on a wide range of pedagogy-related topics and issues. Attendees will also gain resources to implement a sustainable CoP at their own institutions.
COALA update
Russell, Lisa Becksford (2025-10-02)
Delayed Thrombus on Carotid Web: Case Report With Escalation of Treatment
Kodankandath, Thomas V. (Sage, 2022-04)
Carotid artery web is an underrecognized source and is found in about 1-2% of patients with acute ischemic stroke. Although, first described four decades ago, optimal therapy for carotid web is not yet known. Carotid stenting and endarterectomy are increasingly used for carotid web treatment, given its definitive treatment and avoiding the complications associated with anticoagulation. The case reported here is of an ischemic stroke secondary to a mobile thrombus on a carotid web evident on CT angiography and successful definitive treatment with delayed carotid wall stent placement. In young patients who have a diagnosis of ischemic stroke, the carotid web should be on the differential and adequate neuroimaging with either CTA or DSA should be pursued.
Building damage risk in sinking Indian megacities
Sadhasivam, Nitheshnirmal; Ohenhen, Leonard O.; Khorrami, Mohammad; Werth, Susanna; Shirzaei, Manoochehr (Nature Portfolio, 2025-10-28)
Building damage poses serious safety risks, causing substantial financial losses worldwide. Engineering shortcomings are commonly cited as the cause of long-term structural failures, often neglecting the exacerbating role of land subsidence. Here we used satellite radar observations during 2015–2023 to estimate differential settlements at 5 fast-growing Indian megacities, including more than 13 million buildings and 80 million people. Our analysis reveals 878 km² of land subsiding, exposing ~1.9 million people to subsidence rates of more than 4 mm yr−1. An estimated 2,406 buildings across Delhi, Mumbai and Chennai are at high risk of structural damage from ongoing land subsidence. Sustained over 50 years, current subsidence rates could place as many as 23,529 buildings at very high risk of structural damage in Chennai, Delhi, Mumbai, Kolkata and Bengaluru. Our results highlight the compounding risk of infrastructure damage from subsidence, assisting policymakers to develop resilience plans and adaptation strategies that prioritize mitigation and maintenance spending.
Managing the reduction of soil phosphorus can prolong global reserves of fertilizer phosphorus and improve water quality
McDowell, R. W.; Simpson, Z. P.; Doscher, C.; Steinfurth, K.; Mott, Joshua; Margenot, A. J.; Appelhans, S. C.; Elledge, A. E.; Thornton, C. M.; Moore, P. A.; Blackwell, M. S. A.; Cade-Menun, B. J.; Ros, M. B. H.; Pavinato, P. S.; Zavattaro, L.; Soltangheisi, A.; Zhang, T. Q.; Haygarth, P. M.; Burkitt, L.; Fenton, O. (Elsevier, 2025-09)
Excess phosphorus in agricultural soils threatens freshwater quality and long-term fertilizer security. Globally, 27% of soils exceed crop phosphorus needs (plant-available soil test phosphorus as Olsen phosphorus), contributing to runoff that degrades water quality for 3 billion people. Reducing surplus phosphorus through fertilizer cessation (“drawdown”) is low cost, but rates remain poorly understood. We analyzed ∼12,700 observations from 225 trials in 21 countries to model the time for Olsen phosphorus to reach optimal agronomic thresholds across major crops and improved grassland. Drawdown rates ranged from 9 (Oceania and Asia) to 14 (Europe) years. Our model suggests that global drawdown could save ∼190,430 kt of fertilizer, 10 times the annual global use. These findings highlight opportunities to maintain yields, improve water quality, and deliver economic benefits, supporting better-informed agricultural practice and environmental polices worldwide.
Starting a Library Publishing Program: Choosing the Right Technologies
Guimont, Corinne; Potter, Peter J. (Association of College and Research Libraries, 2025-10-27)
Forest dynamics and ecosystem collapse in open-access problems
Cobourn, Kelly M.; Amacher, Gregory S.; Delacote, Philippe; Wang, Haoyu (Cambridge University Press, 2025-08-29)
Changes like the shift of tropical forests into savannah in the Amazon highlight the potential for deforestation to drive ecosystems past potentially irreversible tipping points. Reforestation may avert or delay tipping points, but its success depends on the degree to which secondary and primary forests are substitutes in the production of ecosystem services. This article explores how deforestation, reforestation and substitutability between forest types affect the likelihood that a forest system will cross a tipping point. Efforts to ensure that secondary forests better mimic primary forests only yield a small improvement in terms of delaying ecosystem collapse. The most significant effects on tipping points arise from an increase in the relative costs of clearing primary forests or a decrease in the costs of protecting land tenure in secondary forests. Our results highlight the importance of the latter, which are often ignored as a policy target, to reduce the risk of ecosystem collapse.
Introduction au "Conte de l'or et du silence" de Gustave Kahn
Shryock, Richard L.; Kunkel, Samuel (Du Lérot, 2025)
"Le Conte de l'or et du silence" de Gustave Kahn
Shryock, Richard L.; Kunkel, Samuel (Du Lérot, 2025)
Gustave Kahn et Le Conte de l’or et du silence : une question de lisibilité
Shryock, Richard L. (2024-06-24)
Hydraulic constraints to stomatal conductance in flooded trees
Brennan, Marisa J.; Criscione, Kristopher S.; Olichney, Jacob A.; Ding, Junyan; Fang, Yilin; McDowell, Nate; Wolfe, Brett T. (Springer, 2025-09-10)
Stomatal closure is a pervasive response among trees exposed to flooded soil. We tested whether this response is caused by reduced hydraulic conductance in the soil-to-leaf hydraulic continuum (ktotal), and particularly by reduced root hydraulic conductance (kroot), which has been widely hypothesized. We tracked stomatal conductance at the leaf level (gs) and canopy scale (Gs) along with physiological conditions in two temperate tree species, Magnolia grandiflora and Quercus virginiana, that were subjected to flood and control conditions in a greenhouse experiment. Flooding reduced gs, Gs, kroot and ktotal. Path analysis showed strong support for direct effects of ktotal on gs and for flood duration on ktotal, but not kroot on ktotal. A process-based model that accounted for the ktotal reduction predicted the timeseries of Gs in flood and control treatment trees reasonably well (predicted versus observed Gs R2 = 0.80 and 0.51 for M. grandiflora and Q. virginiana, respectively). However, accounting only for kroot reduction in flooded trees was insufficient for predicting observed Gs reduction. Together, these results suggest that hydraulic constraints were not limited to roots and highlight the need to account for flooding effects on ktotal when projecting forest ecosystem function using process-based models.
Age-related dysregulation of proteasome-independent K63 polyubiquitination in the hippocampus and amygdala
Bae, Yeeun; Venkat, Harshini; Preveza, Natalie; Ray, W. Keith; Helm, Richard F.; Jarome, Timothy J. (Pergamon-Elsevier, 2025-08-06)
Cognitive decline with aging is a complex process involving multiple brain regions and molecular mechanisms. While the role of the canonical protein degradation function of the ubiquitin–proteasome system (UPS) has been well studied in the context of aging and age-associated memory loss, the non-proteolytic functions of ubiquitin activity remain poorly understood. Here, we investigated the role of lysine-63 (K63) polyubiquitination, the most abundant form of proteasome-independent ubiquitination, in aged rats, focusing on the hippocampus and amygdala, two brain regions reported to have cellular and molecular alterations with age that are associated with age-related memory loss. Using an unbiased proteomic approach, we observed a significant increase of K63 polyubiquitination in the hippocampus across the lifespan. Reducing K63 polyubiquitination in the hippocampus of aged male rats using the CRISPR-dCas13 RNA editing system enhanced contextual fear memory, while similar manipulations in middle-aged rats, which typically have normal memory, had no effect, emphasizing the age-dependent role of K63 polyubiquitination in memory formation. Conversely, the amygdala showed a consistent reduction of K63 polyubiquitination protein targets across the lifespan, and further reductions of K63 polyubiquitination improved memory retention in aged, but not middle-aged, male rats. Together, our findings reveal the dynamic and region-specific functions of K63 polyubiquitination in the brain aging process, providing novel insights into its contribution to age-associated memory decline.

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