Oklahoma State University - Stillwater
  • Stillwater, OK, United States
Recent publications
Regional transport pricing is indeed very vital in urban settings where the transportation network is spread out across large areas and can influence travel behavior and the sustainability of cities. Therefore, in addition to existing pricing systems, such as flat fare, distance-based fare, and zonal pricing, this study proposes a sustainable approach to regional rail system pricing using rent prices and a transportation affordability index. The proposed model aims to reduce commuters' overall travel distance in order to reduce air pollution and maintenance costs for public transportation vehicles. Rent-based pricing encourages people to rent houses in regions that shorten their travel distances and fill a gap in the literature on regional rail system pricing by dealing with the decentralization of the cities. A two-step clustering and non-linear optimization modeling approach are proposed based on face-to-face surveys with regional rail system passengers. For various clusters of stations, rent per income rates and rental-based ticket prices were obtained. Furthermore, a sensitivity analysis is conducted to evaluate different conditions of the affordability index and rent prices in the studied regions. Compared to the current pricing system, ticket revenues increased by 3.88% and 1.68% in rent-based pricing.
The whole (or holistic) building design approach is important for sustainability and fire safety. It is, however, challenging to design a building holistically due to it requiring a designer to take into account various design factors and their effects on multiple performances. It is very difficult to do such a design without a proper design tool. This study proposes a performance-based, multi-characteristic optimization tool for a wall-insulation system. The wall-insulation system of a building has multiple performance objectives, such as energy-saving, fire safety, soundproofing, sustainability, and cost. The tool quantifies the performance values of the five objectives and identifies the best combination of sheathing layers and insulation materials based on the quantified performance value. This tool also addresses an issue of the current insulation system design approach in the building code, by proposing a performance-based design approach for a thermal barrier design. The tool is expected to assist architects or building designers in comparing various wall-insulation systems.
Cotton (Gossypium hirsutum , L.) management decisions to abet early growth, fruit set, boll maturation, and harvest preparation are often facilitated by prediction of the date when critical developmental stages are reached. In the U.S., Growing Degree Days calculated with a base 60 ° F (DD60) are commonly used to predict cotton development. Observations suggest development of modern cultivars differs from previously established guidelines. The objectives were to: 1) re‐evaluate DD60s required for an early‐, mid‐ and late‐maturing cultivar to reach key growth stages across the US Cotton Belt; and 2) determine if predictions of growth stages are strengthened by optimizing base temperature or including an upper threshold by growth stage. During 2018 and 2019, 22 field trials were established in 10 states. Plant growth stages were monitored weekly and air temperature was computed from interpolated surface observations weighted by a physical, geographic model. Observed DD60s to reach growth stages varied slightly by cultivar and region (≤85 DD60s and ≤130 DD60s, respectively). Required DD60s to reach growth stages exceeded most published ranges. Optimization of base temperature and inclusion of an upper threshold by growth stage did not substantially decrease errors in predicting date of growth stage occurrence. The DD55 and DD55 with an upper threshold of 86 ° F calculations resulted in slightly lower errors in predicting date of growth stage occurrence than the DD60 calculation. Although guidelines should be updated, it is unlikely slight modification in base temperature or upper thresholds will drastically increase the predictive ability over the DD60 calculation. This article is protected by copyright. All rights reserved
Interferometric methods form the basis of highly sensitive measurement techniques from astronomy to bioimaging. Interferometry typically requires high stability between the measured and reference beams. The presence of rapid phase fluctuations washes out interference fringes, making phase profile recovery impossible. This challenge can be addressed by shortening the measurement time. However, such an approach reduces photon-counting rates, precluding applications in low-intensity imaging. We introduce a phase imaging technique which is immune to time-dependent phase fluctuations. Our technique, relying on intensity correlation instead of direct intensity measurements, allows one to obtain high interference visibility for arbitrarily long acquisition times. We prove the optimality of our method using the Cramér-Rao bound in the extreme case when no more than two photons are detected within the time window of phase stability. Our technique will broaden prospects in phase measurements, including emerging applications such as in infrared and x-ray imaging and quantum and matter-wave interferometry.
In recent years, tactical personnel, especially within the military, have integrated sports science–related practices into their training. This effort has been less pronounced with first responders (police, firefighters, emergency services), despite the structured academy training typically completed by recruits, challenging job tasks and long-term health, fitness, and wellness concerns. One example of how sports science practices could be applied for first responders is through high-performance programs. High-performance programs are commonplace within elite sport and can help set roadmaps for success. Numerous factors contribute to an effective program, much of which relates to the resources provided to personnel. This can include a multidisciplinary team (e.g., strength and conditioning coaches, athletic trainers/medical staff, psychologists, nutritionists, researchers) and appropriate resources (e.g., gyms, facilities, testing and training equipment). This review will discuss whether high-performance programs, or at least components of these programs, could be adopted in first-responder populations. The authors will discuss literature to demonstrate how and why high-performance programs could be implemented for first responders and whether these programs are aspirational, attainable, or objectionable. Finally, the authors will provide actionable high-performance program-related information for the strength and conditioning coach and tactical scientist working with first responders.
The mining industry continues to have considerable adverse effects on ecosystems, which necessitates the development of robust and effective strategies for the remediation of abandoned mine sites. One such approach involves the integration of mineral‐solubilizing microorganisms into existing external soil spray seeding technologies. These microorganisms have the capacity to reduce mineral particle sizes, stimulate plant growth, and facilitate the release of essential soil nutrients. Despite the potential benefits of mineral‐solubilizing microbial inoculants, their impacts on overall soil multifunctionality and microbial communities, associations with microbial diversity, soil multifunctionality, and plant growth remain largely unknown. To bridge these knowledge gaps, we conducted a 1‐year greenhouse experiment, which involved a comprehensive assessment of various parameters including soil nutrients, enzyme activities, functional gene copies, and microbial communities. Our findings unveiled that the application of mineral‐solubilizing microbial inoculants led to a significant augmentation of soil multifunctionality. Additionally, the application of microbial inoculants increased the relative abundances of Bacilli (class), Bacillales (order), Bacillaceae (family), and Bacillus (genus). While no significant relationship emerged between microbial alpha diversity and soil multifunctionality, our investigation found positive correlations between the Bacillus groups, keystone ecological cluster, and soil multifunctionality. Furthermore, our results suggested that the indirect impact of microbial inoculants on plant growth was primarily channeled indirectly through their influence on Bacilli, keystone ecological cluster, and soil multifunctionality, as opposed to changes in the overall bacterial or fungal diversity. Overall, our study underscores the significance of mineral‐solubilizing microbial inoculants for the rejuvenation of abandoned mine sites, while providing valuable insights for future research aimed at optimizing the efficacy of external soil spray seeding techniques.
Animal diseases in production and subsistence environments have the potential to negatively affect consumers, producers, and economies as a whole. A growing global demand for animal sourced food requires safe and efficient production systems. Understanding the burden of animal disease and the distribution of burden throughout a value chain informs policy that promotes safe consumption and efficient markets, as well as providing more effective pathways for investment. This paper surveys existing knowledge on the burden of animal disease across economic categories of production, prevention and treatment, animal welfare, and trade and regulation. Our scoping review covers 192 papers across peerreviewed journals and reports published by organizations. We find there exists a gap in knowledge in evaluating what the global burdens of animal diseases are and how these burdens are distributed in value chains. We also point to a need for creating an analytical framework based on established methods that guides future evaluation of animal disease burden, which will provide improved access to information on animal health impacts.
To detect quickly and accurately “Yuluxiang” pear fruits in non-structural environments, a lightweight YOLO-GEW detection model is proposed to address issues such as similar fruit color to leaves, fruit bagging, and complex environments. This model improves upon YOLOv8s by using GhostNet as its backbone for extracting features of the “Yuluxiang” pears. Additionally, an EMA attention mechanism was added before fusing each feature in the neck section to make the model focus more on the target information of “Yuluxiang” pear fruits, thereby improving target recognition ability and localization accuracy. Furthermore, the CIoU Loss was replaced with the WIoUv3 Loss as the loss function, which enhances the capability of bounding box fitting and improves model performance without increasing its size. Experimental results demonstrated that the enhanced YOLO-GEW achieves an F1 score of 84.47% and an AP of 88.83%, while only occupying 65.50% of the size of YOLOv8s. Compared to lightweight algorithms such as YOLOv8s, YOLOv7-Tiny, YOLOv6s, YOLOv5s, YOLOv4-Tiny, and YOLOv3-Tiny; there are improvements in AP by 2.32%, 1.51%, 2.95%, 2.06%, 2.92%, and 5.38% respectively. This improved model can efficiently detect “Yuluxiang” pears in non-structural environments in real-time and provides a theoretical basis for recognition systems used by picking robots.
Urbanization alters abiotic conditions, vegetation, and wildlife populations in ways that affect tick abundance and tick-borne disease prevalence. Likely due to such changes, tick abundance has increased in many US urban areas. Despite growing public health importance of tick-borne diseases, little is known about how ticks are influenced by urbanization in North America, especially in the central United States where several pathogens occur at or near their highest incidences. To identify factors influencing tick abundance across a gradient of urbanization intensity, we used CO2 traps and flagging to sample ticks at 16 parks across Oklahoma City, Oklahoma, USA over 2 yr, conducted vegetation surveys, and used trail cameras to estimate a deer abundance index. Our results indicate there is a risk of encountering ticks across the entire urbanization gradient from exurban areas to the urban core, although some species (Dermacentor variabilis (Say)) appear less-common in heavily-urbanized areas. Vegetation variables were also associated with tick abundance. For example, Amblyomma maculatum Koch decreased with increasing woody plant and leaf litter cover, and there was a weak positive relationship between D. variabilis abundance and cover of understory eastern redcedar (Juniperus virginiana L.), indicating this native encroaching tree may increase tick populations in urban areas of the Great Plains. The deer abundance index was positively correlated with A. maculatum and D. variabilis abundance but unrelated to A. americanum (L.) abundance. Public health officials and land managers can use such information about parks/greenspaces and their surroundings to focus public education and land management efforts designed to reduce tick-borne disease prevalence.
Some of the most prevalent arthropod-borne pathogens impacting humans in the United States are transmitted by Ixodes ticks. However, little is known regarding the Rickettsia species that inhabit Ixodes scapularis in the United States. The aim of this study was to screen adult I. scapularis collected in central Oklahoma over an 8-yr period for the presence of tick-borne rickettsial pathogens or potential pathogens. During 2014–2021, 112 adult specimens of I. scapularis were collected from central Oklahoma. Amplicons for Rickettsia spp. were amplified from 53 (47.3%) of the samples. Of the positive ticks, 42 (79.2%) amplicon-positive Rickettsia samples were 100% identical to Rickettsia buchneri, 10 (18.9%) were 100% identical to R. tillamookensis strain Tillamook 23, and 1 (1.9%) specimen showed high identity for Rickettsia amblyommatis. This study highlights the importance of considering Rickettsia-specific assays when assessing Ixodes species ticks for potential pathogens.
Simple dilution of semen is the oldest method to process semen for artificial insemination with either fresh or cooled semen. This was developed prior to the optimisation of centrifugation techniques for semen processing through a combination of trial and error and research. Simple dilution is a faster method to process semen, is easy to use and works in many circumstances. For on‐farm semen use a 1:1 (v/v) semen to extender ratio is used. A variety of other techniques have been developed, such as cushion centrifugation, density gradient centrifugation and sperm filtration. Cushion centrifugation is used to concentrate the sperm and allows higher centrifugation speeds than centrifugation alone. This allows for improved recovery rates of sperm. Density gradient centrifugation has been used to select for morphologically normal sperm but suffers from low recovery rates. Processing sperm with this technique can result in improved motility and improved DNA integrity of sperm. Sperm filtration is another method to concentrate sperm without the use of centrifugation; however, it has lower recovery rates compared to cushion centrifugation. This review will discuss these techniques in the application of processing equine semen for either fresh or cooled‐shipped use.
Jennie Duberstein In 2023, the American Ornithological Society (AOS) ­introduced a Conservation Practitioner Award, which recognizes individuals or groups of biologists at any stage of their career for outstanding work in government agencies (from municipal, state, provincial, federal, or international levels) or nongovernmental organizations to ­further the conservation of birds. This award acknowledges the ­planning, on-the-ground, or day-to-day work of ­dedicated professionals addressing avian conservation issues at a local or regional scale. Jennie Duberstein is the winner of the inaugural 2023 AOS Conservation Practitioner Award. Jennie Duberstein is the Coordinator of the Sonoran Joint Venture, one of 25 Migratory Bird Joint Ventures (JVs) across North America and one of just two that span the U.S. and Mexico. As the Sonoran JV coordinator, Dr. Duberstein is responsible for partnership-building for birds and habitat conservation across the southwestern U.S. and northwestern Mexico. She has directed environmental education programs, developed community-based conservation projects in the U.S.–Mexico border region, developed and taught courses and workshops on bird identification, ecotourism, and bird monitoring, and studied species including Double-crested Cormorant and wading birds in Sonora and Yellow-billed Cuckoos in Arizona. Dr. Duberstein is a ­conservation social scientist who has been a leader in advancing equity, diversity, and inclusion in bird conservation. She is also very engaged in education and outreach and has been a long-time camp leader for fledgling young birders, directing field courses, summer camps, and conferences, and generally helping to connect young birders with opportunities and each other.
Strain gauges are often used to measure vertical wheel loads in a railroad track. This approach is based on the concept of differential-shear-strain (DSS) measurement: The difference in vertical shear force between two points along a beam equals the magnitude of the resultant of applied vertical forces in between. With a slight modification to the strain-gauge positions and installation of an additional set of strain gauges, this concept can be extended to measure the vertical rail–tie interface reaction forces, thus assessing the tie support conditions. Although the application of DSS measurements for vertical-wheel-load quantification is widely prevalent in the railroad community, the validity of this approach for tie reaction measurement has been relatively unexplored. Conceptually, the approach is similar to the vertical-wheel-load measurement system, with the only difference being the placement of the strain gauges along the rail. Nevertheless, several questions have been raised about how different track and loading configurations can affect the accuracy of such a measurement system. To address some of these concerns and establish this approach as a viable method for tie support condition assessment, a field-validation effort was undertaken. Under the scope of this research effort, the strain-gauge-based DSS measurement system for rail–tie interface reaction-force measurement was evaluated in the field under static as well as dynamic loading. The study showed that the strain-gauge-based measurement approach is as accurate as other conventional methods of tie reaction-force measurement.
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6,860 members
Dillon Scofield
  • Department of Physics
Bruce Dunn
  • Department of Horticulture and Landscape Architecture
Chaoqun Huang
  • Department of Physiological Sciences
101 Whitehurst, 74078, Stillwater, OK, United States
Head of institution
V. Burns Hargis