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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- Forest and wood products sector workforce survey insightsLarasatie, Pipiet (2025-01-13)This survey is part of a workforce study focused on the forest and wood products sector led by Dr. Pipiet Larasatie. Its aim is to identify and characterize the existing labor force, and it explores issues and opinions around inclusion, recruitment, and retention.
- Red blood cell aggregation within a blood clot causes platelet-independent clot shrinkagePeshkova, Alina; Rednikova, Ekaterina; Khismatullin, Rafael; Kim, Oleg; Muzykantov, Vladimir; Purohit, Prashant; Litvinov, Rustem; Weisel, John (American Society of Hematology, 2025-04-16)Platelet-driven blood clot contraction (retraction) is important for hemostasis and thrombosis. RBCs occupy about half of the clot volume, but their possible active contribution to contraction is unknown. The work was aimed at elucidating the ability of RBCs to promote clot shrinkage. To distinguish effects of platelets and RBCs, we formed thrombin-induced clots from reconstituted human samples containing platelet-free plasma and platelet-depleted RBCs, followed by tracking the clot size. The clots before and after RBC-induced shrinkage were analyzed using histology and scanning electron microscopy. Tension developed in the RBC-containing plasma clots was measured with rheometry and theoretical modeling was used to elucidate the clot shrinkage mechanisms. Platelet-depleted clots formed in the presence of RBCs exhibited >20% volume shrinkage within one hour. This process was insensitive to blebbistatin, latrunculin A, and abciximab. At a higher RBC count clot shrinkage increased, whereas in the absence of RBCs no plasma clot shrinkage was observed. At low platelet counts RBCs stimulated clot contraction proportionately to the platelet level. Inside the shrunken clots, RBCs formed aggregates. The average tensile force per one RBC was ~120±100 pN. Clots from purified fibrinogen formed in the presence of RBCs did not change in size, but underwent shrinkage in the presence of osmotically active dextran. Blood clot shrinkage can be caused by RBCs alone and this effect is due to the RBC aggregation driven mainly by osmotic depletion. The RBC-induced clot shrinkage may reinforce platelet-driven blood clot contraction and promote clot compaction when there are few and/or dysfunctional platelets.
- Empowering Youth: Elevating Teen Voice in Virginia 4-H ElectionsHindman, Benjamin; Hodges, Christine; Moore, Abbigail; Pearson, Jocelyn; Price, Tonya; Proudfoot, Chad; Walton, Malyka; Wright, Carly (2025-04-08)
- General-purpose genotypes and evolution of higher plasticity in clonality underlie knotweed invasionWang, Shengyu; Liao, Zhi-Yong; Cao, Peipei; Schmid, Marc W.; Zhang, Lei; Bi, Jingwen; Endriss, Stacy B.; Zhao, Yujie; Parepa, Madalin; Hu, Wenyi; Akamine, Hikaru; Wu, Jihua; Ju, Rui-Ting; Bossdorf, Oliver; Richards, Christina L.; Li, Bo (Wiley, 2025-04)Many widespread invasive plant species express high phenotypic variation across novel environments, providing a unique opportunity to examine ecological and evolutionary dynamics under global change. However, studies often lack information about the origin of introduced populations, limiting our understanding of post-introduction evolution. We assessed the responses of Reynoutria japonica from 128 populations spanning latitudinal transects in the native (China and Japan), and introduced (North America and Europe) ranges when grown in two common gardens. Plants from introduced populations differed in almost all traits from those from Chinese populations, but were similar to plants from the putative origin in Japan. Compared to Chinese populations, North American, European and Japanese populations expressed lower trait values and plasticity in most traits. However, plants from both introduced and Japanese populations expressed higher clonality and plasticity in clonality than plants from Chinese populations. Further, introduced populations expressed higher plasticity in clonality but lower plasticity in basal diameter compared to Japanese populations. Our findings emphasize the potential role of clonality and plasticity in clonality for invasion success. In addition, our study highlights the importance of comparisons to source populations within the native range to identify evolutionary responses of introduced plants to novel environments.
- A Fast Transient Response Distributed Power Supply With Dynamic Output Switching for Power Side-Channel Attack MitigationLiu, Xingye; Ampadu, Paul (IEEE, 2024-09)We present a distributed power supply and explore its load transient response and power side-channel security improvements. Typically, countermeasures against power side-channel attacks (PSCAs) are based on specialized dc/dc converters, resulting in large power and area overheads and they are difficult to scale. Moreover, due to limited output voltage range and load regulation, it is not feasible to directly distribute these converters in multicore applications. Targeting those issues, our proposed converter is designed to provide multiple fast-responding voltages and use shared circuits to mitigate PSCAs. The proposed three-output dc/dc converter can deliver 0.33-0.92 V with up to 1 A to each load. Comparing with state-of-the-art power management works, our converter has 2× load step response speed and 4× reference voltage tracking speed. Furthermore, the converter requires 9× less inductance and 3× less output capacitance. In terms of PSCA mitigation, this converter reduces the correlation between input power trace and encryption load current by 107×, which is 3× better than the best standalone work, and it only induces 1.7% area overhead and 2.5% power overhead. The proposed work also increases minimum traces to disclose (MTDs) by 1250×. Considering all the above, our work could be a great candidate to be employed in future multicore systems supplying varying voltages and resisting side-channel attacks. It is the first work bridging the gap between on-chip power management and side-channel security.
- Got Followership? Rethinking Leadership from the Other SideKaufman, Eric K. (2025-03-04)90-second presentation for Virginia Tech's 2025 Faculty Nutshell Talks.
- Comparing National Institute of Health Funding for Cancer Survivorship: A Spotlight on Breast and Gynecologic CancersWhite, Payden; Greer, Heather; Armbruster, Shannon (Lippincott, Williams & Wilkins, 2025)Objective: To evaluate the distribution of National Institutes of Health (NIH) funding for breast and gynecologic cancer survivorship research in relation to survivor populations. Methods: A retrospective cohort study was conducted on NIH-funded grants for breast and gynecologic cancer survivorship from fiscal years (FY) 2017–2021 using an existing dataset from the NIH Office of Cancer Survivorship. Grant characteristics, including funding amount, study design, and research focus, were extracted from NIH Reporter and ClinicalTrials.gov. Total funding and per-survivor funding were calculated using prevalence data from the Surveillance, Epidemiology, and End Results (SEER) program. Descriptive statistics were applied to compare funding disparities between breast and gynecologic cancer survivorship research. Results: Among 160 NIH-funded grants on cancer survivorship, 144 (90%) focused on breast cancer, and 16 (10%) on gynecologic cancers. Breast cancer survivorship research received significantly more funding ($188.35 million) compared to gynecologic cancer survivorship research ($15.41 million). Per-survivor funding was also higher for breast cancer ($9.69 per survivor) than for gynecologic cancers ($2.15 per survivor). Most survivorship studies were interventional (60%), with randomized controlled trials as the predominant design. The primary study focus was on late and long-term effects of cancer treatment (53%), followed by health promotion (21%) and care delivery (16%). Conclusion: NIH funding for gynecologic cancer survivorship research is significantly lower than that for breast cancer, even when accounting for survivor prevalence. The findings highlight the need for equitable resource allocation to ensure comprehensive survivorship support for gynecologic cancer survivors. Increased funding and research efforts are necessary to address the unique challenges faced by this population and to optimize long-term outcomes.
- Encounters with Foreign Lands: developing a sensuous empirical approach to reading depthRosier, Shaun (2025-03-28)
- The Cardiovascular Effects of Interleukin-6 Inhibition in Patients with Severe Coronavirus-19 InfectionBinder, Michael S.; Timmerman, Clinton; Marof, Biwar; Wu, Yingxing; Bankole, Adegbenga; Heletz, Ido (SAGE Publishing, 2025-04-02)Objective: The coronavirus disease 2019 (COVID-19) pandemic illustrated the relationship between cardiac arrhythmias and pro-inflammatory states. Pro-inflammatory cytokines, including interleukin-6 (IL-6), have significant effects on cardiac conduction. Atrial or ventricular arrhythmias occurring while infected results in a doubling of mortality. Tocilizumab, a monoclonal antibody that blocks the IL-6 receptor, is associated with improved mortality and is believed to be related to immune modulation of the COVID-19–related hyperinflammatory state. Methods: A single-center retrospective review of all patients with severe COVID-19, defined as admission to an intensive care unit or requirement of respiratory or circulatory support, from March 2020 through March 2022, was conducted. Patients who received or did not receive tocilizumab were grouped into the treatment and control groups, respectively. Results: Four hundred seventy-three patients were reviewed and 400 met the criteria for inclusion in our study. There were 305 patients (age, 63 ± 13 years, 58% male) in the control group and 95 (age, 57 ± 15 years, 51% male) in the treatment group. In-hospital mortality was greatly reduced with tocilizumab compared with controls (44.2% vs 85.9%, p < 0.001) and new-onset atrial fibrillation (AF) showed a statistically significant reduction (17.8% vs 29.5%, p = 0.019). New-onset wall motion abnormalities, potentially related to myocarditis or acute coronary syndrome, also trended toward significance with tocilizumab (7.7% vs 15.7%, p = 0.10). Deep vein thrombosis, pulmonary embolism, stroke, and sustained ventricular arrhythmias did not meet statistical significance. Conclusion: As expected, tocilizumab did show significant improvement in mortality. Tocilizumab also showed a significant reduction of new-onset AF. Other cardiac structural endpoints did not reach statistical significance.
- The review sentiment garden: Blossoming loss aversion and diminishing sensitivity across time and crisisSharma, Abhinav; Shin, Seunghun; Nicolau, Juan Luis; Park, Sangwon (Elsevier, 2025-08)Adopting an approach grounded in prospect theory, this article tests the principles of loss aversion and diminishing marginal sensitivity in hotel review sentiment. While prospect theory has been extensively tested in other areas, its application to review sentiment is novel, thereby extending our understanding of how hotel guests perceive and evaluate their service experiences. Simultaneously, this study examines whether the predictions of prospect theory hold to the same extent in post-Covid-19 reviews as they do in pre-Covid-19 reviews. The analysis is conducted on a sample of 416,756 reviews from 375 hotels in 14 European cities posted between 2000 and 2022. The findings show that a significant level of loss aversion and diminishing sensitivity characterizes reviews from both the pre-pandemic as well as post-pandemic periods. However, the effect of loss aversion becomes even more accentuated after Covid-19, with a gradual return to pre-pandemic levels.
- Use of wearable sensors for continuous field monitoring of upper arm and trunk postures among construction workersPorta, Micaela; Casu, Giulia; Lim, Sol; Nussbaum, Maury A.; Pau, Massimiliano (Taylor & Francis, 2025-02-28)Construction is considered amongst the highest risk sectors for the development of work-related musculoskeletal disorders (MSDs) considering the large number of unfavourable environmental and task-specific factors typical in this sector. Thus, it is important to have quantitative tools to support the assessment of the exposure to physical MSD risk factors. We employed wearable inertial sensors (ISs) to perform a real-world characterisation of static postures and repetitive movements involving the trunk and upper arms (UA), among 15 workers during 2 hours of their regular shifts. IS data were processed according to ISO 11226 and EN 1005-4 standards. We found that workers spent ∼25% of the monitored time in static trunk flexion >20% and more than 50% of the time with UA elevations >20°. The ability to assess working postures for prolonged periods may represent a useful tool for different stakeholders involved in the protection of construction worker health.
- Cognitive workload assessment during VR forklift trainingZahabi, Saman Jamshid Nezhad; Islam, Md Shafiqul; Kim, Sunwook; Lau, Nathan; Nussbaum, Maury A.; Lim, Sol (Elsevier, 2025-05)Virtual Reality (VR)-based training offers a safe and engaging environment for training forklift operators. Given the complexity of forklift operation, monitoring the cognitive workload of novice operators in these virtual settings is essential for optimizing the training process. This study investigated cognitive workload variation during a VR-based training for forklift operators due to varying levels of task difficulty and repeated training. Twenty novice participants completed two sessions in a VR simulator with each session including three forklift driving lessons at three difficulty levels. Perceived workload (NASA-TLX) and normalized encephalographic (EEG) activity were employed to assess cognitive workload. Five of the six NASA-TLX subscales and EEG activity in three distinct frequency bands (theta, alpha and beta) all significantly increased with increasing task difficulty. However, we did not observe significant changes in cognitive workload as measured by EEG in the second training session, highlighting a potential limitation in using EEG to track workload variations across days. Perceived workload and EEG measures showed moderate, positive correlations. Our results highlight the potential of EEG for real-time monitoring of workload during VR-based forklift training, particularly in differentiating tasks of varying difficulty. While more research is needed to confirm measurement consistency across sessions, this capability could facilitate worker monitoring to deliver timely alerts or assistance when workload levels exceed optimal thresholds.
- Perspectives of Mining Personnel on Adopting Occupational Exoskeletons: Comparisons Between a Developed and a Developing CountryAkinwande, Feyisayo; Kim, Sunwook; Ojelade, Aanuoluwapo; Muslim, Khoirul; Iridiastadi, Hardianto; Nasarwanji, Mahiyar; Kim, Jeong Ho; Nussbaum, Maury A. (Springer, 2025-03-01)Occupational exoskeletons (EXOs) have received growing attention as a new ergonomic intervention to reduce physical demands in various industries (e.g., manufacturing, logistics, construction, and agriculture). However, their potential use in mining has not yet been reported. Survey data (n = 135) were obtained from mining workers in the United States (US) and Indonesia (ID). Qualitative and frequency analyses were used to summarize and compare respondents’ perceived barriers, benefits, and promoters to EXO use and adoption. Beta regression analyses were also used to examine whether the perceived likelihood to use arm-support EXOs or back-support EXOs differed between the countries and was affected by demographic or job characteristics, or by perceptions regarding EXOs. Both US and ID respondents reported potential benefits of EXOs for physically demanding tasks such as lifting and overhead work, and they shared concerns about adaptation, uncertainty or lack of knowledge, confined spaces, device weight, potential failure or damage, and costs. However, some key differences also emerged: US respondents were more likely to consider using arm-support EXOs and back-support EXOs, despite expressing concerns about their use; ID respondents, although they reported more existing health and safety hazards, appeared more hesitant about adopting EXOs, possibly due to these additional hazards. These results demonstrate that miners appear to have an interest in EXOs but also emphasize the need to ensure task compatibility, comfort, and affordability to ensure the safe and effective adoption of EXO technology in mining in both developed and developing countries.
- Exploring Student Perceptions of Capstone Design OutcomesLutz, Ben; Paretti, Marie C. (Tempus Publications, 2017)Capstone design courses are pivotal in engineering curricula, and understanding and assessing the resultant learning is critical to both researchers and practitioners. While current scholarship does provide tools for such assessments, most are based on outcomes derived through research with faculty, administrators, and various industry stakeholders. As a result, students' self-reported learning gains have been largely overlooked. Addressing this gap, this paper presents a qualitative thematic analysis that explores student perceptions of capstone learning. Drawingon50semi-structured interviewswith 31 students from three different institutions, we describe four emergent themes: (1) Engineering Design Skills; (2) Teamwork and Communication; (3) Self-directed Learning Skills; and (4) Development of an Engineering Identity. These themes are generally consistent with current outcomes identified from other sources, but students' discussions also highlight areas of personal development that move beyond acquisition of technical and professional skills. That is, students' perceptions of their own learning in capstone reflect not only those outcomes currently desired by various stakeholders and accreditation bodies, but also outcomes that might be more subtle and less tangible than those demonstrated via traditional assessment approaches. Thus, we argue that in order to more meaningfully support student growth, both technical and professional, capstone faculty should incorporate opportunities to actively promote and provide evidence for the kinds of critical reflection that students engage in throughout the course.
- Risk factors for vulvar dysplasia recurrence in patients from southwestern Virginia and surrounding states: A retrospective cohort studyGreer, Heather O.; Metz, Kallie; Locklear, Tonja M.; Armbruster, Shannon D. (Springer, 2025)Objective. To determine whether distance to a tertiary care center is an independent risk factor for recurrence of VIN 2/3 or invasive vulvar cancer. Methods. A retrospective chart review included individuals with VIN 2/3 from southwest Virginia and surrounding states treated at a single institution. The patients were treated from 1/1/2010 to 12/31/2020. Medical records were reviewed for demographics, risks factors, distance to care determined by a geographic information system (GIS) software, treatment modality, and recurrent disease. Results. We identified 251 patients. Most patients were Caucasian (92%) and had history of tobacco use (current [49%] and former [27.5%] tobacco users). Patients traveled an average of 20 miles for care (range: 0.3-113.9 miles). Most commonly, VIN 2/3 was treated with excision (n=136), excision and ablation (n=59), or ablation alone (n=31). The average lesion size was 20 mm (range: 2, 100 mm). Thirty-five percent of patients (n=88) developed recurrent VIN 2/3, on average, 9.6 months (range: 0.1, 7.8 years) following treatment. Recurrences were associated with increased body mass index (p=0.049), immunocompromised status (p=0.039), steroid use (p=0.024), and positive margins (p=0.0003). No subsequent diagnoses of cancer were made. Logistic regression showed that margin status was the only field impacting recurrence (p=0.0075; OR=2.63, 95% CI: 1.30-5.35). Distance to care was not related to recurrence risk (p>0.05). Conclusions. Our findings confirm known risk factors for current disease, while indicating that distance to care does not impact their recurrence. Further research is merited to investigate other recurrence risk factors that were not included in our model.
- Ticam2 ablation facilitates monocyte exhaustion recovery after sepsisCaldwell, Blake A.; Ie, Susanti; Lucas, Amy; Li, Liwu (Nature Portfolio, 2025-01-15)Sepsis is a leading cause of death worldwide, with most patient mortality stemming from lingering immunosuppression in sepsis survivors. This is due in part to immune dysfunction resulting from monocyte exhaustion, a phenotype of reduced antigen presentation, altered CD14/CD16 inflammatory subtypes, and disrupted cytokine production. Whereas previous research demonstrated improved sepsis survival in Ticam2-/- mice, the contribution of TICAM2 to long-term exhaustion memory remained unknown. Using a cecal slurry injection sepsis model, we monitored the establishment and recovery of monocyte exhaustion in Ticam2-/- mice. After one week of recovery, we profiled bone marrow and splenic reservoir monocytes in Ticam2-/- mice and found that, in contrast to the persistent exhaustion observed in wild-type monocytes, Ticam2-/- monocytes largely resembled healthy controls. To determine the impact of TICAM2 ablation on innate epigenetic memory in sepsis, we measured genome-wide DNA methylation in bone marrow monocytes and found that Ticam2-/- cells exhibit a unique profile of altered methylation at CEBPE binding sites and regulatory features for key immune genes such as Dmkn and Btg1. Bearing human translational relevance, a case study of time course blood samples collected from a sepsis patient presenting with SIRS and a positive qSOFA revealed a similar effect in human monocytes, which steadily transition into an exhausted memory characterized by a CD38high; CX3CR1low; HLA-DRlow state within four days of hospital admittance. Together, our data reveal the chronic preservation of monocyte exhaustion, partially controlled by TICAM2.
- Pulmonary metastatic melanoma: current state of diagnostic imaging and treatmentsZhang, Kermit S.; Pelleg, Tomer; Campbell, Sabrina; Rubio, Catalina; Loschner, Anthony Lukas; Ie, Susanti (Future Medicine, 2021-07-09)Melanoma is the deadliest form of skin cancer with an estimated incidence of over 160,000 cases annually and about 41,000 melanoma-related deaths per year worldwide. Malignant melanoma (MM) primarily occurs in the skin but has been described in other organs. Although the respiratory system is generally afflicted by tumors such as lung cancer, it is also rarely affected by primary MM. The estimated incidence of pulmonary MM of the lung accounts for 0.01% of all primary lung tumors. The current understanding of pulmonary MM of the lung pathophysiology and its management are not well established. We aim to survey current clinical modalities with a focus on diagnostic imaging and therapeutic intervention to guide providers in the management of patients with a high index of suspicion.
- Passive arm-support and back-support exoskeletons have distinct phase-dependent effects on physical demands during cart pushing and pulling: An exploratory studyPark, Hanjun; Noll, Alex; Kim, Sunwook; Nussbaum, Maury A. (Elsevier, 2025-03-20)Arm-support exoskeletons (ASEs) and back-support exoskeletons (BSEs) can be effective in reducing physical demands during various occupational tasks, yet evidence of their effects in pushing and pulling tasks remains limited. We examined the effects of using a passive ASE and a BSE on task completion time, shoulder and trunk kinematics, and muscle activity in the shoulder and back while pushing and pulling a moderately loaded (100 kg) cart. Forty volunteers (24 M and 16 F) completed the study. Using the BSE substantially reduced thoracic and lumbar erector spinae muscle activity for males, especially during the initial and ending phases of pushing (by up to ∼31.4 %) and pulling (by up to ∼25.4 %) compared to the No Device (ND) condition. In contrast, using the ASE showed no significant benefits, with females experiencing an increase in anterior deltoid muscle activity (by up to ∼46.3 %) compared to ND. Findings from this study help to understand the effects of BSEs and ASEs in pushing and pulling tasks and support the development of more versatile exoskeletons.
- Gait variability predicts post-fatigue obstacle course performance among military cadets: An exploratory studyUlman, Sophia; Srinivasan, Divya; Nussbaum, Maury A. (Elsevier, 2025-03-12)We explored the extent to which pre-fatigue gait variability during load carriage is associated with the ability of an individual to perform an obstacle course post-fatigue. Twenty-four military cadets were monitored during treadmill gait and completed an obstacle course before and after a full-body fatigue protocol. Gait variability measures were determined from spatiotemporal stride characteristics, joint angle trajectories, and inter-joint coordination. These measures were then used in multiple linear regression models to predict three measures of post-fatigue performance (i.e., hurdle completion time, maximum jump height, and maximum jump distance). Measures of joint kinematic variability predicted 73–89% of the variance in post-fatigue performance. Specifically, the significant predictors were sagittal plane variability of 1) hip angle and hip-knee coordination during swing phase; and 2) knee-ankle coordination during both stance and swing phase. Measures of joint kinematic variability obtained from gait thus appear relevant for predicting individual differences in adapting to fatigue, and such measures could aid in predicting post-fatigue performance in diverse dynamic tasks.
- Understanding the drivers of and barriers to adopting passive back- and arm-support exoskeletons in construction: Results from interviews and short-term field testingAshtiani, Mohamad Behjati; Morris, Wallace; Ojelade, Aanuoluwapo; Kim, Sunwook; Akinwande, Feyisayo; Barr, Alan; Harris-Adamson, Carisa; Akanmu, Abiola; Nussbaum, Maury A. (Elsevier, 2025-05)Construction workers experience high rates of work-related musculoskeletal disorders (WMSDs), particularly affecting the back and shoulders. Exoskeletons (EXOs), including arm-support (ASEs) and back-support (BSEs) devices, have clear potential as ergonomic interventions for reducing WMSD risks, yet the specific benefits and limitations in the construction industry remain largely unclear. We aimed to identify drivers and barriers to adopting EXOs in construction, which was done using a two-phase approach: an interview study involving 24 construction stakeholders, followed by a field study with 22 construction workers. Participants in the interview study had hands-on experiences with diverse EXOs, then provided feedback on initial impressions, perceived barriers, and potential benefits of EXO use. Interview recordings were analyzed for sentiment, systematically categorizing responses as positive, neutral, and negative. During the field study, workers wore EXOs while performing their job tasks for up to 1 h, then completed structured exit surveys that assessed usability, comfort, safety, and overall satisfaction. We found a generally positive view of EXO technology in construction, with stakeholders open to adoption for enhancing productivity and reducing physical demands. However, usability, safety, and social acceptance concerns indicated a need for design improvements focused on comfort and compatibility. Notably, safety concerns expressed by interviewees contrasted with positive field study responses, suggesting that the input obtained can vary between assessment conditions. Future research should include longitudinal studies to track shifts in perception and assess diverse designs. These findings highlight the need for refined EXOs to meet construction demands and support broader industry adoption.