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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Impact of Technology on the Future of Course Development, Design, and Delivery: Leveraging Generative Artificial Intelligence for Greater Accessibility and Inclusion
Talukdar, Shahidur Rashid; Haque, Md Mahim Anjum; Nabi, Syed Tauhidun; Sikdar, Sagor (IGI Global, 2025-09-19)
In this chapter, we argue that generative AI (GenAI) tools can make higher education more accessible and inclusive by transforming course development, design, delivery, and student evaluation. To this end, we identify various GenAI tools and their advantages for educational settings. This chapter further highlights advantages of GenAI in education generally, and particularly, for international students, non-English language users, learners with physical or mental disabilities, slow learners, and elderly learners. We then consider various disadvantages, challenges, and concerns related to AI adoption in education. The chapter stresses that in order for GenAI to be beneficial and make a meaningful contribution to curriculum development and delivery, these concerns need to be addressed. To conclude, we identify several policy implications and offer future directions for scholars, policymakers, and institutional leadership.
Performance of ‘Honeycrisp’ Apple Trees on Several Size-Controlling Rootstocks in the 2014 NC-140 Rootstock Trial after Ten Years
Cline, J. A.; Autio, W.; Clements, J.; Cowgill, W.; Crassweller, R.; Einhorn, T.; Francescatto, P.; Gonzalez Nieto, L.; Hoover, E.; Lang, G.; Lordan, J.; Moran, R.; Muehlbauer, M.; Musacchi, S.; Parra Quezada, R.; Schupp, J.; Serra, S.; Sherif, Sherif; Robinson, T.; Wiepz, R.; Zandstra, J. (2025-09-17)
In 2014, a multi-year orchard experiment of apple Malus x domestica (Borkh) was established at 13 locations in Canada, Mexico, and the United States using ‘Honeycrisp’ as the scion. Seventeen dwarf and semi-dwarf rootstock genotypes were tested, specifically: Budagovsky.10 (B.10), the Cornell-Geneva rootstocks G.11, G.202, G.214, G.30, G.41, G.890, G.935, G.969, the Malling rootstocks M.7, MM.106, and the Vineland rootstocks V.1, V.5, V.6, and V.7. The industry standard Malling rootstocks M.26 EMLA and M.9-T337 were included for comparison purposes. Tree mortality, trunk cross-sectional area, tree canopy size, amount of rootstock suckering, yield, and fruit number were measured annually. All measured parameters were influenced by location and rootstock, and the interaction of these two factors was significant. Overall, after 10 years and averaged over all locations, rootstock vigor separated into three distinct rootstock classes: those similar to M.9-T337 (G.11), those similar to M.26 EMLA (G.935, G.41, B.10, G.214, G.969), and those more vigorous than M.26 EMLA (V.1, G.30, M.7, V.7, MM.106, V.6, G.890, V.5). G.202 performance was unusual and therefore was omitted from data analysis. Cumulative yields were generally greater on trees with the highest vigor. Averaged over all locations, all Geneva, Vineland, and Budagovsky rootstocks had cumulative yields higher than the industry standards M.9-T337 and M.26 EMLA. The newer rootstocks B.10, V.5, V.6, V.7 and all the Geneva rootstocks, had good to excellent cumulative yields. G.890 stood out as having exceptional cumulative yield among all the rootstock genotypes evaluated. Averaged over all locations, cumulative yield efficiency was greatest for M.9-T337 and all the Geneva rootstocks, as well as B.10. Overall, the strong rootstock by location interaction on cumulative yield observed in this trial illustrates the importance of testing rootstocks at a regional level. These results are reflective of orchard vigor and yields after 10 years and provide apple producers with performance indicators to make more informed decisions concerning rootstock selection for their orchard training systems and planting locations using a weak scion cultivar.
Polarization-Space Modulation With Reconfigurable Intelligent Surfaces, Robust Estimation, and Quaternion Neural Networks
Buvarp, Anders M.; Mili, Lamine M.; Mishra, Kumar Vijay; Zaghloul, Amir I. (IEEE, 2025-06)
Contemporary communications systems use large arrays in order to exploit the spatial domain requiring multiple radio-frequency (RF) chains leading to prohibitive cost and power consumption. Spatial degrees of freedom are also achieved by utilizing the polarization states of an electromagnetic (EM) wave. To this end, we propose a polarization-state modulation system based on carrier-wave reflections from a reconfigurable intelligent surface (RIS), where a sequence of data bits is mapped to polarization states. We consider a system with an upper millimeter-wave or low-terahertz (THz) RF source so that the channel model is line-of-sight-dominant. The data symbol constellation consists of 16 quaternion-valued symbols, of which two correspond to linear polarizations and the remaining 12 represent elliptical polarizations. Our channel models consist of both additive white Gaussian noise (AWGN) and impulse noise. We utilize the Weiszfeld algorithm and generalized M-estimators (GM-estimators) to handle the impulse noise and robustly decode the polarization-space modulated (PSM) signals. Furthermore, we train and evaluate quaternion neural networks (QNNs) for decoding PSM signals using seven different activation methods. Our numerical experiments indicate that the RIS is capable of directing signal power toward the location of the receiver. The bit error rate performance of our QNNs and robust decoders exceeds that of OFDM-BPSK.
Robust Media-Based Modulation With an Eisenstein Constellation Generated by a Reconfigurable Intelligent Surface With Blind Equalization and Complex-Valued Neural Receivers
Buvarp, Anders M.; Mili, Lamine M.; Fishbone, Justin A. (IEEE, 2025-02)
Recent research has proposed media-based modulation (MBM) as a method to reduce the hardware complexity of wireless communications systems and therefore also achieve a reduction of the associated cost. In this work, we propose an MBM system based on a novel asymmetric signal constellation consisting of scaled and shifted Eisenstein integers. The constellation is generated by phase shifts induced by a reconfigurable intelligent antenna, where the magnitudes are modulated by turning on or off certain numbers of reflecting elements. At the receiver, a uniform linear antenna array is used to capture the incident electromagnetic planar wave. Robust estimation techniques, such as the median, the Weiszfeld algorithm, and the Sq -estimator are employed to recover the constellation points. A novel gain control scheme is proposed together with a phase offset detection method based on circular cross-correlation. Furthermore, complex-valued convolutional neural networks are used as decoders. We consider the performance of our system under impulse noise caused by voltage transients in addition to additive white Gaussian noise and show superior performance vis-Ã -vie a generic 64-QAM modulation scheme and a brute-force arithmetic method based on the four-quadrant arctan function and the median. Furthermore, we compare our system performance with hexagonal QAM-MBM and QAM-MBM.
Fast Critical Clearing Time Calculation for Power Systems with Synchronous and Asynchronous Generation
Wang, Xuezao; Xu, Yijun; Gu, Wei; Liu, Kai; Lu, Shuai; Korkali, Mert; Mili, Lamine M. (IEEE, 2025-07)
The increasing penetration of renewables is replacing traditional synchronous generation in modern power systems with low-inertia asynchronous converter-interfaced generators (CIGs). This penetration threatens the dynamic stability of the modern power system. To assess the latter, we resort to the critical clearing time (CCT) as a stability index, which is typically computed through a large number of time-domain simulations. This is especially true for CIG-embedded power systems, where the complexity of the model is further increased. To alleviate the computing burden, we developed a trajectory sensitivity-based method for assessing the CCT in power systems with synchronous and asynchronous generators. This allows us to obtain the CCT cost-effectively. The simulation results reveal the excellent performance of the proposed method.
A combinatorial approach to avoiding weak keys in the BIKE cryptosystem
Matthews, Gretchen L.; McMillon, Emily (Springer, 2025-08-01)
Bit Flipping Key Encapsulation (BIKE) is a code-based cryptosystem that was considered in Round 4 of the NIST Post-Quantum Cryptography Standardization process. It is based on quasi-cyclic moderate-density parity-check (QC-MDPC) codes paired with an iterative decoder. While (low-density) parity-check codes have been shown to perform well in practice, their capabilities are governed by the code’s graphical representation and the choice of decoder rather than the traditional code parameters, making it difficult to determine the decoder failure rate (DFR). Moreover, decoding failures have been demonstrated to lead to attacks that recover the BIKE private key. In this paper, we demonstrate a strong correlation between weak keys and 4-cycles in their associated Tanner graphs. We give concrete ways to enumerate the number of 4-cycles in a BIKE key and use these results to present a filtering algorithm that will filter BIKE keys with large numbers of 4-cycles. These results also apply to more general parity check codes.
Long-term impacts of 48-h water and feed deprivation on blood and performance responses of grazing Bos indicus Nellore heifers
Abreu, Mateus J. I.; Marques, Rodrigo S.; Cidrini, Iorrano A.; Batista, Luis H. C.; Ferreira, Igor M.; Oliveira, Karla A.; Cruz, Vinicius A.; Limede, Arnaldo C.; Sousa, Luciana M.; Franca, Matheus Q. S.; Bisio, Gustavo H. M.; Siqueira, Gustavo R.; Resende, Flavio D. (Oxford University Press, 2024-02)
The study investigated the effects of 48-h water and feed deprivation on blood and the performance of grazing Nellore (Bos indicus) heifers. Twenty-four Nellore heifers (initial body weight [BW] = 238 ± 10 kg; age = 16 ± 2 mo), were ranked by initial BW and age and randomly assigned to one of the two treatments: (1) grazing animals with free access to pasture, water, and mineral-mix (CON; n = 12), or (2) the same grazing conditions but deprived of pasture, water, and mineral-mix for 48 h (DPR; n = 12). The paddocks consisted of Urochloa brizantha cv. Marandu, using a continuous and fixed stocking rate. The experiment lasted 225 d, with the first 14 d considered as the adaptation period (days −14 to −1) and the subsequent 211 d as the evaluation period (days 0 to 211). From days 0 to 2, treatments were applied by keeping the DPR heifers in pens and reintegrating them into the experimental area after a 48-h water and feed deprivation. Individual full BW was recorded on days −14, −13, −1, before (day 0) and after (day 2) treatment application, and on days 6, 11, 12, 41, 42, 210, and 211. Blood samples were collected in the morning on days 0, 2, 6, 12, and 211. A treatment effect was detected (P < 0.001) for shrink BW from days 0 to 2, which was greater (P < 0.001) in DPR vs. CON heifers. Subsequently, DPR animals were lighter (P < 0.001) compared with CON heifers by the end of the deprivation period (day 2). From days 4 to 211, DPR was lighter (P < 0.001) compared with CON heifers after treatment application and for the entire experimental period. In the first 10 d after treatment application (days 2 to 12), DPR heifers showed a partial compensatory average daily gain (ADG; P < 0.001) compared with CON heifers, while no significant differences were observed in ADG between the treatments from days 12 to 42 and 42 to 211 (P > 0.420). Overall ADG (days 2 to 211) was greater (P < 0.001) for DPR vs. CON heifers. All serum variables, except AST, were higher (P < 0.001) in DPR than in CON heifers on day 2 after treatment application. Our study demonstrates that grazing Nellore heifers subjected to 48-h water and feed deprivation experienced significant alterations in their blood metabolites and BW immediately after the stressful event. Although the deprived heifers partially compensated for their BW loss in the early days post-deprivation, they remained 12 kg lighter than the non-deprived animals throughout the production cycle. Routine management practices in beef cattle operations, such as shipping and receiving at feedlot facilities, may cause the animals to go without food and water for extended periods. The findings of this study reveal that Nellore (Bos indicus) heifers subjected to a 48-h water and feed deprivation exhibited substantial changes in their blood metabolites and lost 14.6% of their body weight by the completion of the deprivation period. Although the deprived heifers showed a partial compensatory increase later, they remained 12 kg lighter than the non-deprived heifers throughout the production cycle.
Effect of forage quality and narasin inclusion on ruminal fermentation, nutrient intake, and total tract digestibility of Nellore steers
de Paula, Matheus Felipe Freitas Viana; Marques, Rodrigo S.; Pires, Alexandre Vaz; Soares, Leticia Carolina Bortolanza; Limede, Arnaldo Cintra; Ferreira, Evandro Maia; Polizel, Daniel Montanher (Oxford University Press, 2024-08-02)
The study aimed to evaluate the effects of forage quality and narasin inclusion on intake, digestibility, and ruminal fermentation of Nellore steers. Twenty-eight rumen-cannulated Nellore steers (initial body weight [BW] = 350 ± 32.4 kg) were allocated to individual pens in a randomized complete block design, with 7 blocks, defined according to the fasting BW at the beginning of the experiment. The steers were randomly assigned within blocks to 1 of 4 experimental diets in 2 × 2 factorial arrangements, being the first-factor forage quality (MEDIUM = 81 g of CP/kg of dry matter [DM], and HIGH = 153 g of CP/kg of DM), and the second factor was the inclusion (N13 = diet plus 13 mg/kg of DM of narasin) or not (N0) of narasin (Zimprova; Elanco Animal Health, São Paulo, Brazil). The experiment consisted of a 28-d period with 22 d for adaptation and the last 6 d for data collection. No haylage quality × narasin interaction (P ≥ 0.68) was observed on DM and nutrient intake. Haylage quality affected (P ≤ 0.01) DM intake, with greater values observed for steers fed HIGH compared with MEDIUM haylage. There was an increase (P < 0.001) in OM, NDF, hemicellulose, and CP intake for steers consuming HIGH vs. MEDIUM haylage. Including N13 did not affect (P > 0.39) DM and nutrient intake of steers. No haylage quality × narasin interactions were detected (P ≥ 0.60) for total tract nutrient digestibility. However, steers fed with HIGH haylage showed an increase (P > 0.001) in DM and digestibility of all nutrients compared with MEDIUM. Steers fed a MEDIUM haylage had a greater (P < 0.01) proportion of acetate compared with steers fed HIGH during all evaluated hours. Steers fed HIGH haylage had a greater (P < 0.01) proportion of propionate at 0 h compared with steers consuming MEDIUM, whereas at 12 h, steers consuming MEDIUM hay had a greater (P < 0.01) proportion of propionate vs. HIGH haylage. A haylage quality × narasin and haylage quality × time of collection interactions were detected (P ≤ 0.03) for rumen ammonia concentration, which was reduced (P < 0.03) in N13 vs. N0 steers consuming HIGH haylage. Collectively, high-quality haylage allows increased consumption and digestibility, with more energy-efficient ruminal fermentation. In addition, narasin might be an important nutritional tool in forage-based diets to enhance the ruminal fermentation parameters of Bos indicus Nellore steers.
Using audio-visual monitoring to evaluate immune and behavioral indicators to lipopolysaccharide challenge in beef cattle
Limede, Arnaldo C.; Marques, Rodrigo S.; Cidrini, Fernando A. A.; Souza, Gilyard A. P.; Santos, Erollykens F.; Wu, Xiaohui; De Souza, Izadora S.; Qualharello, Tamara; Cooke, Reinaldo F.; Chen, C. P. James (Oxford University Press, 2025-10)
This experiment investigated the integration of camera and microphone monitoring with AI technologies to assess immune responses, activity patterns, and respiratory acoustic changes in beef cattle using lipopolysaccharide (LPS) administration as a model. Twelve Angus steers [age = 15 ± 1 mo; body weight (BW) = 399 ± 6 kg] were housed in four feedlot pens (3 steers/pen). On day 0, steers were ranked by initial BW, and assigned to one of two groups in a crossover design, with treatments initiated at hour 0: 1) an intravenous bolus dose of bacterial LPS (0.5 μg/kg of BW; n = 12), or 2) 5 mL intravenous injection of 0.9% sterile saline (CON; n = 12). The experimental period lasted 9 days (days -3 to 6) with 20 days of washout between periods. Video footage was recorded, and animal positions were tracked using a deep learning-based object detection algorithm (YOLOv11). Video frames were used to generate activity heatmaps for three consecutive one-hour intervals: h 0-1, 1-2, and 2-3. Microphones mounted on each animal's halter were used to measure differences in breathing patterns. Steers rectal temperature was assessed, and blood samples were collected at hours 0, 4, 8, 24, 48, 72, and 96 relative to treatment administration. LPS induced a neuroendocrine response by increasing plasma cortisol concentrations (P ≤ 0.04) at 4, 8, and 12 h, non-esterified fatty acid (NEFA) at 8, 12, and 24 h, while reducing (P < 0.01) circulating beta-hydroxybutyrate (BHBA) at 4 and 8 hours vs. CON group. LPS steers displayed an increase (P < 0.01) in rectal temperature at 4 and 12 h, and a reduction (P < 0.01) in intake at 24, 48, and 72 h post-challenge vs. CON cohorts. The YOLOv11 identified reduced pen exploration and increased clustering behavior among LPS steers 1.5 h post-challenge. Spatial analysis of steer movement further confirmed that LPS steers exhibited increased resting behavior and avoided the feeding bunk throughout the 3-hour window. In parallel, Mel spectrogram analysis of breathing sounds 2 hours after LPS revealed an altered respiratory pattern in LPS steers, characterized by short, sharp, and high-pitched sounds suggestive of labored breathing. Collectively, LPS administration elicited behavioral and physiological changes, which were detected using integrated AI-driven video and audio monitoring systems. These findings suggest that these technologies may offer a promising approach for real-time assessment of cattle behavior and respiratory dynamics in cattle.
Ruminant nutrition symposium: novel microbial solutions to optimize production efficiency in beef and dairy systems
Cappellozza, Bruno I.; Cooke, Reinaldo F.; Amaral, Rafael C.; Bach, Alex; Engle, Terry E.; Ferraretto, Luiz F.; Marques, Rodrigo S.; Miller, Alexandra C.; Moriel, Philipe; Vendramini, Joao M. B. (Oxford University Press, 2025-05)
The livestock industry is in search of sustainable technologies that enhance the profitability and sustainability of food animal production. Among these technologies, microbial solutions include living bacteria that may support soil, plant, and animal health. Bacterial inoculants have been the most used additives to modulate whole-plant corn silage fermentation, including homo- and heterofermentative bacteria. Bacterial inoculants can improve fermentation characteristics of grass silage, whereas the wide variation in chemical composition and management practices across cool- and warm-season grasses makes the outcome of inoculation less predictable. Tailored recommendations for bacterial inoculant species and strains, based on species and management practices, are necessary to increase the predictability of silage inoculation, including whole-plant corn and grass silage. Microbial solutions are also used as feed additives for beef and dairy cattle, including Bacillus-based direct-fed microbials (DFM). Recent advancements in Bacillus-based DFM supplementation have shown promise for enhancing cow-calf productivity through improved gut health, immune function, and nutrient metabolism. Incorporating Bacillus-based DFM into stocker and feedlot receiving programs can improve feed intake and digestibility, health, and productivity of high-risk cattle. Bacillus-based DFM have also been used in feedlot diets to address public concerns with antimicrobial resistance but also to improve cattle performance and reduce the incidence of diseases. Multispecies bacterial-based DFM are promising alternatives to counteract the potentially adverse effects of Salmonella, as these DFM supported the integrity of the intestinal epithelial cells under in vitro settings. In dairy cattle, most DFM-related research in mature cows has targeted improvements in rumen fermentation and enterocyte health. In general, improvements in milk production due to supplementation of bacteria-based DFM seem to be more consistent than those obtained with yeast-based DFM. Collectively, microbial solutions have the potential to optimize silage quality, enhance feed intake and digestibility by ruminants, and support cattle health and performance while fostering sustainable practices in beef and dairy production systems.
Biopolitics at the Nexus of Chronic and Infectious Diseases
Brantly, Nataliya D. (Springer, 2025-02-06)
Non-communicable (chronic) and communicable (infectious) diseases constitute the leading causes of death worldwide. They appear to impact populations in developed and developing nations differently with changing trends in the landscape of human conditions. Greater understanding of changing disease burdens should influence the planning of health programs, the implementation of related interventions, and policymaking efforts on a national and global scale. However, the knowledge of disease burdens does not reflect how states and global health organisations prioritise their efforts in addressing them. This work aims to address the discrepancy in public health priority setting by improving our understanding of how the two disease categories impact the human condition. It reviews two case studies, COVID-19 and type 2 diabetes, as representative cases of an infectious and a chronic disease, respectively, to answer the following question. How does biopolitics, as the governance of human bodies, at the nexus of infectious and chronic disease, impact national and global public health priorities? This work contextualises and reframes the relationship towards disease categories by focusing on three primary themes: risk, current public health interventions, and funding priorities for each case study analysed. It argues that the politics over life at the nexus of chronic and infectious diseases, best conceived as future-oriented economic optimisation, directs the efforts of prioritisation in healthcare based on risk and responsibility-based relationship between multiple stakeholders.
Global Implications of Diabetes Biomedicalization
Brantly, Nataliya D. (Springer, 2025-10-08)
Diabetes remains one of the leading causes of death globally, with its prevalence and associated costs rising despite advances in pharmaceuticals and biomedical technologies. This paper offers a critical, conceptual analysis of how biomedical technologies are reshaping diabetes care by expanding treatment and risk categories associate with type 1 diabetes and prediabetes. Drawing from science and technology studies and critical public health perspectives, the paper uses two illustrative examples, Tzield, an FDA-approved pharmaceutical designed to delay the onset of symptomatic type 1 diabetes, and Continuous Blood Glucose Monitors (CGMs), increasingly used by individuals without a diabetes diagnosis, to examine how biomedical interventions target populations deemed “at risk.” The paper analyzes these technologies as examples of a broader trend: the biomedicalization of risk and the expansion of pharmaceutical and device markets into pre-diagnostic states. It introduces the concept of the “diabetes paradox” to underscore how the exploitation of risk perception in diabetes care may inadvertently undermine the intended benefits of new treatments. It demonstrates that shifting perceptions of risk not only create new burdens and afflictions but also broaden the definition of “at-risk” populations. Furthermore, the paper discusses the global implications of biomedicalization that focus on future risk mitigation rather than addressing current global health challenges.
Open-Source Hearing Aids: A Look into the Future of Medical Technology and Coding
Struyk, Brooke (Tech for Humanity Lab, 2026-01-07)
Hearing loss affects a large portion of the global population, yet the prices for hearings aids continue to increase. With quality devices costing an upwards of $2000 per pair, and lasting between three to seven years depending on the model, access to these technologies has become more unreachable [1]. Over-the-counter hearing aids cost $100 and more, depending on the manufacturer. However, people with mild to severe hearing loss would not be able to use such devices [2]. Open-source hearing aids could be an effective alternative to current FDA-approved hearing aids. Open-source hearing aids not only offer a more affordable alternative but also allow patients to customize and create their own unique devices. This may include adjustable sound profiles, specific molding to the ear, aesthetic modifications, etc. This blog post aims to discuss open-source hearing aids, their pros and cons, and how they can be used in the future for the advancement of technology in medicine. With the new technological advancements and developments in Artificial Intelligence (AI), the idea of patients being involved with creating their own devices may lead to a better and more inexpensive direction for the healthcare field.
Changing Trends in U.S. Digital Health Security
Brantly, Nataliya D. (Tech for Humanity Lab, 2025-04-11)
Healthcare in Wartime Ukraine
Brantly, Nataliya D. (Tech for Humanity Lab, 2026-01-05)
This internet publication shares reflections from my recent trip to Ukraine (2025), where I conducted interviews and gathered data in Ivano-Frankivsk, Lviv, and several surrounding communities. I spoke with health care providers and patients to understand their perspectives on the state of Ukraine’s health care system, the impact of ongoing reforms, and the challenges of accessing essential resources during wartime. This research was approved by the Virginia Tech Institutional Review Board (IRB #25-028) and the Ukrainian Institute of Public Health Policy (IRB #2025-2). While peer-reviewed publications are forthcoming, what follows offers an early glimpse into these findings.
The U.S. Health System Vulnerabilities
Brantly, Nataliya D. (Springer, 2025-12-04)
The increasing integration of health information technology (health IT) into the U.S. healthcare system has brought both opportunities for improvement and new vulnerabilities. The 2024–2030 Federal Health IT Strategic Plan emphasizes equitable data access, quality representative data, and the responsible use of artificial intelligence (AI) to improve health outcomes. Yet, the growing complexity of digital infrastructures has amplified risks related to privacy and the security of protected health information (PHI). This study examines U.S. health system vulnerabilities by analyzing reported PHI breaches and situating them within evolving federal health IT priorities.
A Molecular Biology-Based Practical Examination Used in a Capstone Laboratory Course for Biochemistry Majors
Hite, Kristopher (Elsevier, 2025-05)
A hands-on summative assessment was developed in a capstone laboratory course for biochemistry majors to evaluate students' ability to independently execute several molecular biological techniques simultaneously. These techniques included plasmid DNA quantification, assembling a series of restriction enzyme (RE) digests, loading an agarose gel, electrophoresis, imaging the resultant RE digest fragments, and finally, using deductive reasoning to interpret the banding pattern to draw a well-labeled restriction fragment map. A 3-page prompt was sent to students 48 hours prior to coming to the practical examination to provide time to prepare tables and protocols to successfully execute the experiments necessary for the restriction fragment map construction. Students were provided with a 200 ng aliquot of the pBR322 plasmid of unknown concentration. After using a Qubit fluorometer to determine DNA concentration students were told to use XmnI and BamHI REs to digest the plasmid and to save at least 40 ng of the original unknown plasmid aliquot to load on the agarose gel. Students were not told the exact identity of the plasmid nor were they told how many restriction digests to perform. The average time to complete this practical was approximately 3 hours and all students achieved interpretable gel image results. This exam was developed as an alternative to enzyme kinetics-based exams typically used in the same course for many years. All reagents necessary for this exam are commercially available making it easily adoptable.
Cash crops or cover crops? The reasons and barriers for adopting cover crops in the Southern Great Plains of Texas and Oklahoma
Jamar, Patrick; Fuller, Emily R.; Leggette, Holli R.; Lu, Peng; Wald, Dara M.; Berthold, Troy Allen; deVilleneuve, Stephanie (Frontiers, 2025-10-15)
Water conservation practices such as cover crop adoption have been promoted as effective strategies to improve water quality and soil health. However, cover crop adoption rates have remained low in Texas. A better understanding of the barriers to farmer cover crop adoption can highlight new pathways, encouraging conservation practice adoption across regions of the U.S. Our study examined reasons and barriers to cover crop adoption, including farmers’ demographics and farm characteristics. Using guidance from social cognitive theory and the theory of social normative behavior, we also examined how personal, cognitive, and environmental factors shaped farmers’ behaviors. The data collection process took place starting May 5, 2022, and ending December 30, 2022. A random sample of 3,000 participants was selected from the 88 counties in the Southern Great Plains of Texas and Oklahoma, using the 2021 USDA farm payment payees’ online files. Data were collected using a cross-sectional survey to describe characteristics of farmer populations (e.g., farmers, ranchers, land managers). Results indicated adaptors were largely 51–70 years old (58.3%), female (55.6%), and white (94.4%), with a majority being highly educated [i.e., having a graduate (22.2%) or bachelor’s (36.1%) degree]. Moreover, adoption reasons increased as farmers attained smaller income amounts from agricultural products. Of farmers who adopted cover crops, 38.9% did not use irrigation while 22.2% irrigated between 81 and 100% of their farmed land. Most adopters (61.8%) farmed annual crops. Adopters and non-adopters were significantly different in their environmental and economic barrier perceptions for cover crop adoption. We conclude by discussing situational and economic factors driving these findings and providing opportunities for future research.
Identifying deep leverage points to destabilize ‘lock-in’ and empower farmers in the Midwestern agrifood system
Wald, Dara M.; Coberley, Denise D.; Morris, Chris; Arbuckle, J. G.; Fuller, Emily R. (Springer, 2025-12-01)
Agricultural systems in the Upper Midwest region of the US are highly productive by some measures. Yet at the same time, these systems do not adequately sustain farmers, rural communities, or land and water resources. This challenge has contributed to calls for transformations to enhance sustainability and reduce the vulnerability of conventional agrifood systems. A socio-technical transformation of this size and complexity will require a collective effort among a network of actors. In other contexts, collaborative processes to encourage collective action among diverse network actors have been stymied by lock-in mechanisms (e.g., institutional, material, and cognitive). Here we examine network actors’ perceptions of the current barriers and problems facing the agrifood system of the Upper Midwest and opportunities for change and solutions for creative destabilization to overcome lock-in. Using interviews with network actors and the Constant Comparative Method, we identified salient barriers, including shared concern over limited resources to facilitate change and differences in actors’ vision for change. Yet many participants appeared to agree on solutions to destabilize prevailing industry resistance to change, including shifting power to farmers, providing resources for farmers to leverage their discursive legitimacy, and challenging cognitive sources of lock-in.
A cost-benefit analysis for use of large SNP panels and high throughput typing for forensic investigative genetic genealogy
Budowle, Bruce; Arnette, Andrew; Sajantila, Antti (Springer, 2023-09)
Next-generation sequencing (NGS), also known as massively sequencing, enables large dense SNP panel analyses which generate the genetic component of forensic investigative genetic genealogy (FIGG). While the costs of implementing large SNP panel analyses into the laboratory system may seem high and daunting, the benefits of the technology may more than justify the investment. To determine if an infrastructural investment in public laboratories and using large SNP panel analyses would reap substantial benefits to society, a cost–benefit analysis (CBA) was performed. This CBA applied the logic that an increase of DNA profile uploads to a DNA database due to a sheer increase in number of markers and a greater sensitivity of detection afforded with NGS and a higher hit/association rate due to large SNP/kinship resolution and genealogy will increase investigative leads, will be more effective for identifying recidivists which in turn reduces future victims of crime, and will bring greater safety and security to communities. Analyses were performed for worst case/best case scenarios as well as by simulation sampling the range spaces with multiple input values simultaneously to generate best estimate summary statistics. This study shows that the benefits, both tangible and intangible, over the lifetime of an advanced database system would be huge and can be projected to be for less than $1 billion per year (over a 10-year period) investment can reap on average > $4.8 billion in tangible and intangible cost-benefits per year. More importantly, on average > 50,000 individuals need not become victims if FIGG were employed, assuming investigative associations generated were acted upon. The benefit to society is immense making the laboratory investment a nominal cost. The benefits likely are underestimated herein. There is latitude in the estimated costs, and even if they were doubled or tripled, there would still be substantial benefits gained with a FIGG-based approach. While the data used in this CBA are US centric (primarily because data were readily accessible), the model is generalizable and could be used by other jurisdictions to perform relevant and representative CBAs.

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