North Carolina State University Research Articles

External Moderation of Reactor Core Neutrons for Optimized Production of Ultra-Cold Neutrons

The ultra-cold neutron (UCN) source being commissioned at North Carolina State University’s PULSTAR reactor is uniquely optimized for UCN production in the former graphite-filled thermal column outside of the reactor pool. The source utilizes a remote moderation design, which is particularly well suited to the PULSTAR reactor because of its high thermal and epithermal neutron leakage from the core face. This large non-equilibrium flux from the core is efficiently transported to the UCN source through the specially designed beam port in order to optimize UCN production at any given reactor power. The increased distance to the source from the core also greatly limits the heat load on the cryogenic system. A MCNP (Monte Carlo N-Particle) model of this system was developed and is in good agreement with gold foil activation measurements using a test configuration as well as with the real UCN source’s heavy water moderator. These results established a firm baseline for estimates of the cold neutron flux available for UCN production and prove that remote moderation in a thermal column port is a valuable option for future designs of cryogenic UCN sources.

Porter v. Board of Trustees of North Carolina State University et al.

Free Speech

Trends in the management of horses referred for colic evaluation preceding and during the COVID‐19 pandemic (2013–2023)

SummaryBackgroundThe COVID‐19 pandemic represented a significant source of anxiety and stress for equine veterinarians and clients, with the potential for measurable effects on caseload and owner economics.ObjectiveTo compare the number of horses presenting for emergency colic evaluation and treatment, as well as costs at two equine referral hospitals.Study designRetrospective cohort.MethodsMedical records of horses admitted to North Carolina State University (NCSU) and Bell Equine Veterinary Clinic (BEVC) were compared. Total equine accessions, number of horses referred for colic and patient age were recorded over an 11‐year period (2013–2023). Horses were categorised based on treatment as medical, surgical treatment with recovery, surgical exploration with intraoperative euthanasia, or euthanasia without surgery. Total invoice of each case was also recorded.ResultsTotal equine accessions, total number and proportion of horses presenting for evaluation of colic, and number of horses recovering from colic surgery at NCSU increased following onset of the pandemic, while they remained similar to pre‐pandemic levels at BEVC. The proportion of horses presenting for colic that received surgery decreased at both hospitals over the study period. Mean invoice totals for horses surviving colic surgery increased at both hospitals over the study period, but was not significantly associated with euthanasia. Age was not significantly different between categories of colic.Main limitationsRetrospective study design, differences in academic and private practices.ConclusionsThe decreasing proportion of horses admitted for colic that received surgery is likely due to the increased caseload of first‐opinion care at referral practices during the pandemic, as fewer options were available to owners. The increasing number of horses euthanised intraoperatively or euthanised without receiving surgery may be due to the dramatically rising costs of medical care, particularly surgery.

Numerical investigations of shock/boundary-layer interaction and control for Mach 2.5 flow in an axisymmetric inlet

The present work investigates the application of vortex generators for separation control in axisymmetric isolator flows. Reynolds-Averaged Navier-Stokes computations were performed to simulate a Mach 2.5 flow past a half-isolator geometry with a 20∘ axisymmteric compression ramp based on the experiments of Funderburk and Narayanaswamy at North Carolina State University. Single vortex generator and a vortex generator array placed upstream of the shock-induced separation region were investigated. Near wall streamlines, surface pressure contours and density contours on crosswise planes were compared with experiments for flow control using a single vortex generator. Results indicate that the present computations are able to capture the wake and shock structures, and also predict reduction in the streamwise extent of flow separation downstream of the device trailing edge. Finally, the effects of the shape/orientation (forward facing/backward facing) of a single vortex generator, and the design of an array of three vortex generators (with devices of similar and mixed orientations) on the flow separation were also investigated. Contours of near-surface streamwise velocity showed that device orientation had a strong effect on separation control, which is attributed to the differences in the primary streamwise vortices shed in the two cases. Further, the overall reduction in the footprint of separated flow was determined to be most with the use of an array of vortex generators with mixed orientations.

First report of Fusarium oxysporum f. sp. lactucae causing wilt on greenhouse-grown lettuce in North Carolina.

In August 2023, butterhead lettuce (Lactuca sativa L.) presented wilting, chlorosis, and about 2 cm of reddish-tan internal discoloration in the crown from a commercial greenhouse in Orange County, North Carolina. Plant collapse beginning with the outer leaves near the soil surface was observed with 25% disease incidence. Symptomatic lettuce plants were submitted to North Carolina State University's Plant Disease and Insect Clinic. Vascular tissue from symptomatic crowns were cut into pieces, and surface-sterilized in 10% NaOCl for two minutes. The tissue was rinsed in sterile deionized water three times, blotted dry, and placed on acidified potato dextrose agar (APDA). Three isolates, each from a different symptomatic plant, were transferred to APDA and Spezieller Nährstoffarmer agar (SNA) with pieces of sterile filter paper on the surface of the SNA media and incubated for 14 days at 23°C in the dark. Each isolate produced micro and macroconidia consistent with the morphological description of Fusarium oxysporum Schlechtendahl emend. Snyder & Hansen (Leslie and Summerell 2006). DNA was extracted from 15-day-old fungal colonies grown on APDA media using the DNeasy Plant Mini Kit (Qiagen, Germantown, MD, U.S.A.). The intergenic spacer locus was amplified using two primer pairs, iNL11/CNSa and iCNS1/NLa, and sequences were aligned together to form a single contig (O'Donnell et al., 2009). Primers EF1/EF2 were used to amplify the elongation factor 1-alpha region (O'Donnell et al., 1998). Each isolate was deposited into GenBank with accession numbers PP216479, PP216480, PP216481, PP235836, PP235837, and PP235838. Individual isolates revealed a 100% query cover and identity match with sequences of F. oxysporum f. sp. lactucae (FOL) and >99% identity with F. oxysporum CBS 144134 type material accessions in GenBank using BLASTn. A comparison with previously described lettuce isolates showed a homologous match with FOL race 1 isolates from California (MH412701), Arizona (DQ837658), and Greece (OQ466116), and race 4 isolates from Italy (MK801787) and Spain (OP903519). Each isolate was verified as FOL using specific primers FLA0001F/FLA0001R for FOL based on sequence tagged site markers designed by Shimazu et al. (2005). To confirm Koch's postulates, fifteen 21-day-old lettuce cv. Red Tide plants were inoculated with FOL (isolate FOLNC_660). During transplanting, lettuce roots were submerged in a 1 × 105 conidia/mL suspension for five minutes, following an inoculation protocol from Schmale and Gordon (2003). The lettuce plants were placed separately in 8.9 × 8.3 cm pots containing potting soil and maintained in a greenhouse with 31°C daytime and 25°C nighttime temperature, relative humidity of 60%, and 12-hour photoperiod. After 15 days, 80% and 86.7% of infected plants exhibited wilting, chlorosis, and vascular discoloration. The fifteen control plants remained symptomless for both experimental runs. FOL was recovered from the vascular tissue of all symptomatic plants. To our knowledge, this constitutes the first report of FOL infecting lettuce in North Carolina. Fusarium wilt of lettuce has been reported in California (Hubbard and Gerik 1993), Arizona (Matheron and Koike 2003), and most recently in Florida (Murray et al., 2020). The presence of FOL in North Carolina may result in significant crop loss for commercial growers. One of the most effective management strategies is to plant lettuce cultivars that are resistant against FOL.

Development and evaluation of parallel simulated annealing algorithm for reactor core optimization problems

Background The optimization of core loading patterns in nuclear reactors is one of the most studied optimization problems in nuclear engineering due to the enormous economical and safety benefits. Various algorithms such as Genetic Algorithms (GA), Simulated Annealing (SA), and Parallel Simulated Annealing (PSA) have been used in the past for such problems. Methods In this work, a PSA algorithm was developed and integrated into the Modularly Implemented Design Assistance Suite (MIDAS), a framework developed at North Carolina State University to solve nuclear engineering problems. The effectiveness of PSA was compared against the GA and SA algorithms available in MIDAS for a Pressurized Water Reactor first cycle core loading pattern optimization problem. Results PSA consistently generates more optimal solutions than SA and GA by having the higher average fitness, and showing less variance in its performance and thus being more robust. This provides confidence in the PSA implementation within MIDAS. The obtained loading pattern positions high reactive fuel in peripheral locations and low reactive fuel towards the centers in a strategy resembling both Out-In-Checkboard and L3P loading pattern approaches. Conclusions Future studies will involve applying the PSA algorithm to other optimization studies in larger combinatorial spaces, such as in multi-cycle optimization problems.

Judge rules against doctoral student

Case name: Manning v. North Carolina State University, et al., No. 5:23‐CV‐331 (E.D. N.C. 03/19/24).

Ultrasound biomicroscopic imaging parameters associated with outcome in equine infectious ulcerative keratitis and stromal abscesses.

To determine the predictive value of corneal ultrasound biomicroscopy (UBM) findings for the outcome of equine corneal disease. 46 horses with a clinical diagnosis of either infectious ulcerative keratitis or stromal abscess. Corneal UBM (VevoMD; UHF70; VisualSonics) of horses with infectious corneal disease presenting to the North Carolina State University Equine Ophthalmology Service from 2019 to 2023 were evaluated. Size and depth of lesion, presence of Descemet membrane disruption (DMD), corneal thickness, and aqueous humor cell counts (AHCC) were assessed. Comparisons of UBM and clinical exam findings, presence of infectious organisms, and outcome (healed or enucleated) were performed. The UBMs from 46 horses were evaluated. Increased AHCC was significantly associated with increased size and depth of corneal lesions on UBM but not with DMD. Deep lesions and DMD were significantly associated with an enucleation outcome. Horses treated with systemic antibiotics had significantly lower AHCC on UBM, but there were no differences in AHCC with the use of other systemic or topical medications. There was no significant correlation between infectious disease results, clinical findings (aqueous flare or cells), outcome, and UBM AHCC. Parameters on UBM, such as depth of lesion, DMD, and AHCC, may be useful diagnostic and prognostic tools to augment the ophthalmic exam of horses with corneal disease. The UBM findings of deep corneal lesions and DMD suggest a poor prognosis and warrant aggressive surgical intervention.

Facilitating aerospace engineering senior design: Integrating lab curriculum redesign with student project and new technologies

AbstractThis study addresses a gap in existing literature by exploring the impact of an aerodynamics laboratory course on students' readiness for senior design projects in Aerospace Engineering at North Carolina State University. The redesigned curriculum focuses on propellers, aligning with the increasing popularity of senior design projects involving fixed‐wing aircraft and multi‐rotor systems in the Mechanical and Aerospace Engineering Department. The updated course incorporates Additive Manufacturing (AM) and an anechoic chamber for the first time, outlining its structure, objectives, and pivotal concepts. The use of data acquisition codes streamlines experimentation while integrating AM accelerates practical applications of blade element theory (BET). Through an assessment of lab report grades, this initiative significantly enhances students' grasp of propeller concepts, marking a pivotal step in their preparation for senior design projects.

Analysing a campaign as a lens to the future: A case study

On 31st December, 2021, North Carolina State University concluded a successful, nearly ten-year US$2.1bn fundraising campaign, breaking past both the initial US$1.6bn goal and the US$2bn stretch goal. Simultaneous with celebrating their success, the institution looked back at donor behaviour across its campaign period for insights to leverage in future advancement operations. This paper analyses the reviewing of donor behaviour in NCSU’s ‘Think and Do’ campaign. The paper starts by giving background information and then presents the findings. By analysing donor behaviour throughout the campaign, NCSU discovered how institution-specific priorities allowed leadership to strategise around the next campaign, as well as how alumni and donors can best be reached.

Faculty peer-to-peer learning and support online during difficult times: Main types of interactions and engagement during structured faculty conversations

The Faculty Conversation Series at North Carolina State University, offered by the Office for Faculty Excellence, is a virtual option to connect faculty across campus to discuss topics immediately relevant to the unique teaching needs that we are currently experiencing, ranging from technical aspects of teaching online to mental health needs of faculty and students. The purpose is to engage faculty in discovery and discussions that will be helpful to their teaching practice. To this end, we provide the attendees with reading materials, invite a subject matter expert, and facilitate a confidential conversation among interested faculty members in a secure online learning environment. In this article, we discuss the outcomes of the first year of this program, both qualitatively and quantitatively, including a content analysis of written faculty comments collected during the sessions, as well as best practices to organize similar meetings and to facilitate this kind of inclusive faculty engagement.

In Case You Haven't Heard…

Can bird‐watching improve mental health? A new study has found that people who have nature‐based experiences report better well‐being and lower psychological distress than those who do not, a North Carolina State University news release stated. Bird‐watching in particular yielded promising results, with higher gains in subjective well‐being and more reduction in distress than more generic nature exposure, such as walks. Because bird‐watching is an easily accessible activity, the results are encouraging for college students, who are among those most likely to suffer from mental health problems, the news release indicated. “Bird‐watching is among the most ubiquitous ways that human beings interact with wildlife globally, and college campuses provide a pocket where there's access to that activity even in more urban setting, said Nils Peterson, corresponding author of the study and a professor of forestry and environmental resources at North Carolina State University. The paper, “Birdwatching linked to increased psychological well‐being on college campuses: A pilot‐scale experimental study,” was published in Environmental Psychology.

Feasibility of hemoperfusion using extracorporeal therapy in the horse.

Develop, implement, and monitor for adverse effects of, a novel hemoperfusion therapy in adult horses. A prospective, observational feasibility study using three healthy adult horses from the North Carolina State University teaching herd. Health status was determined by physical exam, complete blood count, coagulation panel, and serum biochemistry. Each horse was instrumented with a 14 Fr × 25 cm double-lumen temporary hemodialysis catheter and underwent a 240 min polymer-based hemoperfusion session. Horses were administered unfractionated heparin to maintain anti-coagulation during the session. Given the novelty of this therapy in horses, each horse was treated as a learning opportunity that informed an iterative process of protocol development and modification. Our long-term goal is to investigate potential clinical applications of hemoperfusion in horses, including cytokine reduction in horses with severe SIRS/sepsis. Horses were monitored for changes in clinical exam, biochemistry and hematology parameters. Additionally, cytokines were quantified to determine whether extracorporeal hemadsorption therapy alone caused an inflammatory response. Our results show that hemoperfusion therapy was associated with decreased platelet counts and serum albumin concentration. There was no significant change in plasma cytokine concentrations with hemoperfusion therapy. In one horse, the cytokine concentrations decreased, as previously reported with hemoperfusion therapy in humans. We hypothesized that hemoperfusion therapy could be performed in healthy adult horses without significant adverse effects. Polymer-based hemoperfusion is a feasible extracorporeal therapy (ECT) modality for adult horses. Additional studies are needed to further establish clinical protocols, as well as establish efficacy of polymer-based hemoperfusion for treatment of various conditions in horses, including intoxications, immune-mediated conditions, and sepsis.

PSII-10 Development of an interdisciplinary undergraduate and graduate course in precision livestock farming systems

Abstract The modern livestock industry is increasingly adopting data, technologies, and automation into daily husbandry and management routines and decisions. These advances in precision livestock farming (PLF) enable improved financial margins, sustainability, efficiency, and animal productivity and welfare. However, there is currently a gap between the engineers and data scientists designing the technologies and the animal scientists and caretakers using them. At North Carolina State University a novel course on PLF Systems for undergraduate and graduate students was developed in the Department of Animal Science. Through lecture delivery, livestock production scenarios, scientific literature, and data-based homework assignments students explored data collection, management, analysis, and data-based decision making. Students gained hands-on experience with a variety of sensor types and signal processing through lab-based activities. Basic hardware and software development concepts were explored during an Arduino-based microcontroller activity. The course was developed and refined using student feedback to include additional sensor and lab-based days and additional in-class supported activities utilizing Excel for data manipulation, processing, and presentation. Self-reported student learning results were collected across two semesters (19 students; 18 Animal Science, 1 Biological Engineering) with84% of students indicated the course was effective in increasing their ability to evaluate and implement technology in livestock production systems and 74% of students reported increased knowledge of coding and software, as well as their ability to clean, analyze, and make sense of raw data. The topics and delivery methods implemented in this course could inform the basis for development of similar interdisciplinary PLF courses at other academic institutions.

Postmortem pathologic findings in dogs that underwent total body irradiation and hematopoietic cell transplant: A case series of five dogs with B-cell multicentric lymphoma.

Alternative therapies that can help achieve complete remission in dogs with lymphoma include total body irradiation and hematopoietic cell transplant, though there are few reports describing successes and pathologic sequelae of these procedures. During a 10-year period, 94 dogs with multicentric lymphoma received a hematopoietic cell transplant following total body irradiation at North Carolina State University College of Veterinary Medicine. Seven of these 94 dogs (7%) died prior to discharge, five (5%) of which presented for postmortem examination. Of these dogs, four received an autologous hematopoietic cell transplant, while one received a haploidentical allogeneic hematopoietic cell transplant. All five dogs had bone marrow depletion with all hematopoietic lines affected. Three had systemic candidiasis, while two had bacterial infections. To the authors' knowledge, this is the first report to document pathologic findings and development of systemic mycoses in dogs post total-body irradiation therapy and hematopoietic cell transplant.

Living in Illusion is Dangerous

Abstract The interview given by Marina F. Bykova, Professor of Philosophy at the Department of Philosophy and Religious Studies at North Carolina State University (USA), and the Editor-in-Chief of the journal Studies in East European Thought. She earned her PhD and Dr. Habil in Philosophy from the Institute of Philosophy, Russian Academy of Sciences (Moscow, Russia), where she worked until relocating to the USA in 2000. Bykova specializes in the history of nineteenth century continental philosophy, with a particular focus on German idealism. She has also written extensively on Russian philosophy and intellectual tradition. She has published 11 books and over 250 scholarly articles. Her forthcoming book, Hegel’s Philosophy of Nature: A Critical Guide, is set to be released by Cambridge University Press in 2024.

ARTISANS—Artificial Intelligence for Simulation of Advanced Nuclear Systems for Nuclear Fission Technology

The objective of this Technical Opinion Paper (TOP) is to provide an overview of the research topics in the ARTISANS (Artificial Intelligence for Simulation of Advanced Nuclear Systems) research group at the North Carolina State University. We will discuss the connections between our research with the key items outlined in the Virtual Special Issues (VSI) Nuclear Fission Technology (NFT) series. NFT is crucial for the global goal of decarbonization, but as outlined by the VSI framework, significant challenges remain that inhibit NFT profitability. Our research addresses some of these challenges, centered around improving the simulation of complex nuclear systems with Artificial Intelligence and Machine Learning (AI/ML). The ARTISANS group specializes in many aspects of applications of AI/ML to nuclear engineering, whose potential impact on NFT continues to grow as AI/ML technologies improve.

Hemadsorption extracorporeal therapy removes cytokines ex vivo in horses.

Plasma cytokine adsorption has shown benefit as an adjunctive therapy in human sepsis but has yet to be investigated in horses. We hypothesized that ex vivo filtration of equine plasma with a novel cytokine adsorption device would significantly reduce concentrations of lipopolysaccharide-stimulated cytokines. We also hypothesized that the device would adsorb medications commonly used to treat sepsis. 8 horses owned by North Carolina State University. Four liters of heparinized whole blood was collected from healthy adult horses (n = 8) and stimulated with lipopolysaccharide (100 ng/mL) for 6 hours (37 °C.) from June 4, 2023, to December 15, 2023. Plasma was filtered through a cytokine adsorption device or sham circuit. Samples were collected at 11 time points for multiplex cytokine analysis. Chemistry analysis was performed before and after filtration. To investigate the impact of the device on medication concentrations, equine plasma containing potassium penicillin, gentamicin, and flunixin meglumine was filtered through the cytokine adsorption device or sham for 6 hours. Drug concentrations before and after filtration were determined by ultra-high-performance liquid chromatography. Prefiltration versus postfiltration sample concentrations were analyzed by Student paired t test using GraphPad Prism 9.0 (P < .05). Filtration of lipopolysaccharide-stimulated equine plasma (n = 8) for 6 hours resulted in significant mean reductions in the cytokines IL-10, IL-5, IL-8, tumor necrosis factor-α (TNF-α), and IL-1β, as well as albumin. Drug concentrations of potassium penicillin, gentamicin, and flunixin meglumine were also significantly reduced by filtration. This work provides proof of concept for further investigation of extracorporeal cytokine adsorption as a potential adjunct treatment for equine sepsis.

Optimal Mating of Pinus taeda L. Under Different Scenarios Using Differential Evolution Algorithm

Abstract A newly developed software, AgMate, was used to perform optimized mating for monoecious Pinus taeda L. breeding. Using a computational optimization procedure called differential evolution, AgMate was applied under different breeding population sizes scenarios (50, 100, 150, 200, and 250) and candidate contribution scenarios (maximum use of each candidate was set to 1 or 8), to assess its efficiency in maximizing the genetic gain while controlling inbreeding. A population of 962 Pinus taeda parents with a known pedigree from the North Carolina State University Tree Improvement Program was used to optimize objective functions accounting for the coancestry of parents and expected genetic gain and inbreeding of the future progeny. AgMate results were compared with those from another widely used mating software called MateSel. For the proposed mating list of 200 progenies, AgMate resulted in an 83.7% increase in genetic gain compared with the candidate population. There was evidence that AgMate performed similarly to MateSel in managing coancestry and expected genetic gain, but MateSel was superior in avoiding inbreeding in proposed mate pairs. The developed algorithm was computationally efficient in maximizing the objective functions and flexible for practical application in monoecious diploid conifer breeding. AgMate, with its open-source software, free-to-modify algorithm and front-end ShinyApp, is a necessary addition for the advancement of conifer breeding. Study Implications: A dataset from a breeding population of loblolly pine (Pinus taeda L.) was analyzed using an optimal mating software, AgMate (developed by the authors), to optimize the selection, contribution, and mating of candidates simultaneously. The software helps breeders decide on trees to cross and the crossing frequency, such that the trees are unrelated and would result in the best-performing progenies. AgMate is effective in meeting the breeding objectives for monoecious diploid species. The open-source, easy-to-use, and flexible AgMate software, also accessible via a website, is invaluable in helping breeders create optimal matings for future generations, which balances the pursuit of maximizing genetic gain while maintaining genetic diversity.

The people behind the papers - Julia Grzymkowski and Nanette Nascone-Yoder.

As the digestive system develops, the gut tube lengthens and convolutes to correctly package the intestine. Intestinal malrotation is a prevalent birth anomaly, but its underlying causes are not well understood. In this new study, Nanette Nascone-Yoder and colleagues show that exposure of Xenopus embryos to atrazine, a widely-used herbicide, can disrupt cellular metabolism in the developing gut tube and lead to intestinal malrotation. We caught up with first author Julia Grzymkowski and corresponding author Nanette Nascone-Yoder, Professor at North Carolina State University, to hear more about the story.