Open Research Oklahoma (Oklahoma State Univ.)
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Preventive effects of red ginseng on an aging hallmark - senescence
No full textBy 2030, 1 in 6 people in the world will be aged 60 years or older, increasing the importance of interventional therapies for age-associated diseases. Research investigating cultural dietary differences recognized that the use of herbal medicine supplementation such as processed Panax ginseng, referred to as red ginseng (RG), increases lifespan in Asian countries by facilitating healthy aging. However, the mechanism for how RG prevents, delays, or reverses aging-related diseases is unknown. Thus, this study assessed how RG facilitates healthy aging by identifying cellular and molecular mechanisms of hepatic senescence pathways in an aged mouse model.Lew Wentz FoundationNutritional Science
Oklahoma agriculture’s role in reducing greenhouse gas emissions
No full textThe Oklahoma Cooperative Extension Service periodically issues revisions to its publications. The most current edition is made available. For access to an earlier edition, if available for this title, please contact the Oklahoma State University Library Archives by email at [email protected] or by phone at 405-744-6311
Adhesive pads in anurans: Their origin, shape, and performance
No full textUnveiling the origins of morphological diversity in functional traits can be difficult, particularly when diverse structures purportedly have the same function. Doing so thus requires a focus on how performance maps onto morphology. Here, I addressed several topics regarding the evolution of adhesive pads in frogs. First, I estimated the number of times adhesive pads independently originated in anurans, using pad presence-absence data from 1297 species and multiple methods to determine the upper and lower bounds of independent origins. I found that adhesive pads most likely evolved once at the base of Neobatrachia, a major clade containing 95% of all anuran species. Moreover, I found that adhesive pads have been lost and regained multiple times. Next, I characterized pad shape for 785 species, then tested for a correlation between adhesive-pad shape and the underlying bone structure, namely whether the terminal phalanges are mediolaterally expanded, using a subset of 292 species. I then used model fitting to address the order of evolution for adhesive-pad shape and its underlying bone structure. Adhesive-pad shape correlated with the underlying bone structure, though the order in which these morphologies evolved was unclear. Finally, I collected adhesive performance data for seven species to test for differences in adhesive performance across pad shapes. There were no differences in performance for one shape metric, though the other correlated with adhesive performance on some substrates and not others. Overall, my thesis provides insight into how morphological diversity develops and the consequences of that diversity in a relatively poorly understood system
Estimating live fuel moisture content in Oklahoma plants
No full textLive fuel moisture content (LFM) is an important variable in fire danger rating systems. LFM collection is time and resource intensive and plant water relations vary within and between species. Consequently, the best approach for estimating LFM is unknown. Few studies have investigated LFM in the state of Oklahoma, and current estimates of LFM have not been validated. The objectives of this study were to evaluate the use of environmental and remote sensing proxies for estimating LFM in Oklahoma plants. I found that LFM can be accurately estimated using either hyperspectral leaf-level reflectance or environmental proxies. My analysis of several remote sensing vegetation indices identified the Water Index and VIgreen as the best suited indices for approximating LFM. Using functional group, photoperiod, vapor pressure deficit, and rainfall I was able to estimate LFM in Oklahoma plant communities. In addition to these findings, I identified a need to reevaluate current methods for estimating LFM. By advancing our understanding of LFM and how best to predict it, my results can be used in fire danger rating systems to protect lives and preserve natural resources
Design and operations of multi-hour stratospheric solar hot-air balloons
No full textSolar balloons, also known as heliotropes, are solar-powered lighter-than-air vehicles. Dueto its many benefits, they have potential use in applications requiring high-altitude balloons. Solar balloons are made from low-cost lightweight materials that absorb solar radiation for buoyant lift and can carry an average two-pound payload up to over 20 km (70,000 feet). Recent developments in zero-pressure solar balloons have demonstrated longer flight times (12-hour flights), more accurate flight path and altitude predictions, rapid deployment, and robust construction. One downside of solar balloons is the lack of control during flight. Since solar balloons float in the stratosphere, it is hard to know in real time how the envelope is reacting to the environment. Non-ideal circumstances at that high of an altitude occur such as if the stratosphere is too turbulent and the balloon envelope is falling apart, or the winds at altitude are changing the predicted path of the heliotrope. To mitigate these types of circumstances potential changes to the design of the balloon envelope and a way to control the balloon’s altitude would be beneficial. Changing the balloon envelope design can provide more robust operations to carry larger payloads aloft and mitigate failures due to circumferential stresses. Tetrahedral shaped balloons ”tetroons’ are one example of this. In addition, a vent system within the balloon envelope can change altitude, and by way provide a method of limited trajectory control, by venting buoyant lifting gas. This effort compares the results of various envelope designs and flight results.The discussion of multiple flight campaigns is provided in this effort. These flight campaigns vary from month-long campaigns with NASA Jet Propulsion Laboratory and Sandia National Labs studying the effects of infrasonic events from earthquakes at the stratospheric level as a proof of concept for ballooning on Venus, to providing test launches for future campaigns to understand the feasibility of launching a heliotrope pre-dawn or testing multiple envelope designs to provide more robust flight options for larger payloads
Strategies to extend forage production window in bermudagrass pastures
No full textIn Oklahoma, bermudagrass-based cattle producers rely on summer bermudagrass [Cynodon dactylon (L.) Pers.] production excess to feed cattle from late fall to early spring. However, this excess forage may not be produced in dry years, and if good summer rainfall allows for forage surplus, harvesting hay is costly. Stockpiling bermudagrass is an alternative strategy to provide winter feed. Nevertheless, the low forage quality of stockpiled bermudagrass necessitates supplementation, meaning extra costs. On the other hand, winter wheat (Triticum aestivum L.) is a high-quality forage commonly cultivated in the area. Thus, interseeding winter wheat in dormant bermudagrass pastures may provide high-quality forage for the spring. Thus, our objective was to compare the total forage yield and quality of three different forage production systems: (i) in-season bermudagrass (BER), (ii) in-season + stockpiled bermudagrass (BER+STOCK), and (iii) interseeded winter wheat into bermudagrass (BER+WHEAT). Data were collected near Perkins, OK, in 2021 and 2022. The experiment was set in a randomized complete block design with four replications. The main plots were six bermudagrass varieties, and the subplots were the three different forage production systems. In-season bermudagrass forage was collected every six weeks (three harvests) during the summer, stockpiled bermudagrass forage was collected in the winter, and interseeded wheat forage was collected in late spring. Samples were dry, forage yield calculated, and nutritive value indicators analyzed. The BER+WHEAT system had the highest total forage production, followed by BER+STOCK and BER. In addition, almost half of the total forage produced in the BER+WHEAT was during late spring. The BER+WHEAT system increased total forage production while maintaining similar quality to in-season bermudagrass. Although the BER+STOCK system increased forage total season forage production compared to BER, its nutritive value was low, necessitating supplementation
Optimal and learning-based control of powered knee exoskeletons for lifting tasks
No full textWearable robots, sometimes known as exoskeletons, are incredible devices for improving human strength, reducing fatigue, and restoring impaired mobility. The control of powered exoskeletons, on the other hand, is still a challenge. This necessitates the development of a technique to simulate exoskeleton-wearer interaction. This study presents (1) a two-dimensional (2D) human skeletal model with a powered knee exoskeleton for predicting the optimal lifting motion and assistive torque, (2) a powered knee exoskeleton’s performance comparison between optimal and biomechanical assistive torque control strategies in lifting task, and (3) a hybrid model that utilizes a model-based optimization method to generate training data and an artificial neural network (ANN) based learning method to offer real-time exoskeleton support in lifting activities. The electromechanical dynamics of the exoskeleton DC motor are modeled in the lifting optimization formulation. For the optimal control method, an inverse dynamics optimization formulation is utilized for lifting motion prediction with knee exoskeletons. The design variables are human joint angle profiles and exoskeleton motor current profiles. The normalized human joint torque squared is minimized subject to physical and lifting task constraints. Then, the nonlinear programming (NLP) optimization problem is solved by the gradient-based optimizer SNOPT. The optimal and biomechanical exoskeleton torques are implemented through a two-phase control strategy in real time to provide optimal and biomechanical assistance in human lifting. For the learning-based approach, the learning-based control model is trained using the general regression neural network (GRNN). Once GRNN is trained, the learning-based control model can provide exoskeleton assistive torque in real-time for lifting tasks based on the subject data and box input data. Experimental validations of the optimal and biomechanical control with 6 Nm and 16 Nm maximum assistive torques, and learning-based control with 16 Nm are presented. The 16 Nm maximum optimal, biomechanical and learning-based assistances of the exoskeletons help to reduce activations of the knee extensor and flexor muscles compared to lifting without the exoskeletons. It is observed from the comparison between optimal and biomechanical assistive torques that both control methods have a significant impact on reducing muscle activations for the specific muscle groups. Finally, the learning-based control method can generate assistive torque profiles in real-time and faster than the model-based optimal control approach
Speedfest Black Team senior design
No full textNote: There is no true "written" report to accompany this senior design project. The Chief Engineer led a team of 21 other seniors, and they presented a large portion of the critical design review (submitted below as the project 'report'). The following summarizes the project and its outcome.Speedfest is an engineering competition in which college students design, build, and fly high-performance remote controlled aircraft. This year's mission was to design an aircraft which used electric and rocket propulsion systems. The OSU Black Team and OSU Orange team optimized the aircraft, per the missions, to glide, perform a pylon race, and hit a maximum speed. Oklahoma State Black Team won the competition, with a final tally of nine flags in the pylon race (based on a glide time of approximately a minute) and a maximum speed of 223 miles per hour
Public interest in cardiac arrest in the United States following Damar Hamlin’s injury on Monday night football
No full textObjectives: During a National Football League (NFL) game on Monday, January 2, 2023, a 24-year old athlete, Damar Hamlin, experienced cardiac arrest after a tackle on the field. Experts are suggesting this event was caused by commotio cordis, a condition where blunt force trauma disrupts the electrical activity of the heart. Due to rapid response by team medical staff, including cardiopulmonary resuscitation and the use of an external defibrillator, Hamlin survived this episode and has had positive clinical outcomes. Thus, our primary objective was to quantify the degree of which this episode triggered public interest in cardiac arrest, commotio cordis, and cardiopulmonary resuscitation.Study Design: We performed a temporal analysis of search query volume of the Google search engine via Google Trends (trends.google.com).Methods: Google Trends was used to extract daily search interest related to topics of “cardiac arrest,” and “cardiopulmonary resuscitation” and injury of “commotio cordis” within the United States for a 90 day time frame from October 12, 2022 through January 8, 2023. Search interest from Google Trends is reported as relative search interest (RSI) on a scale from 0-100—where 100 is the peak interest within the searched timeframe. Dates that resulted in RSI < 1 were imputed as 0.5. We constructed an autoregressive integrated moving algorithm (ARIMA) to project search interest for each of these topics if the injury to Damar Hamlin had not occurred. From this model, we compare the forecasted values to the actual values to determine the increase in RSI immediately following the injury.Results: RSI for ‘cardiac arrest’, ‘cardiopulmonary resuscitation’, and ‘commotio cordis’ each peaked (RSI=100) on Januray 4, 2023—the day following the injury to Damar Hamlin (the game was scheduled Monday night). The forecasted RSI for ‘cardiac arrest’ on this day was 0.99 (0.04-1.94)—a difference in RSI of 99.01, which was 10,023.46% increase above the expected value. The forecasted value for ‘cardiopulmonary resuscitation’ on this day was 3.99 (2.03-5.95)—an increase for the actual value of 2,407.65%. The term ‘commotio cordis’ had relatively little prior RSI to this specific injury resulting in a forecasted value for January 4, 2023 of 0.11 (-0.30-0.53). The peak of 100 for the RSI of ‘commotio cordis’ was an 87,268.42% increase.Conclusion: Through Damar Hamlin’s unfortunate cardiac arrest, which occurred during a televised NFL game, followed by immediate mass media attention, public interest in cardiac arrest, commotio cordis, and cardiopulmonary resuscitation increased as evidenced by our results. Increased interest in these topics could advance interest in cardiac arrest prevention and increase effectiveness of bystander interventions, such as cardiopulmonary resuscitation
Exploring the meanings of change in student-athlete activism through the perceptions and experiences of Black and non-Black student-athletes attending PWIs
No full textThe purpose of this study was to seek the perspectives of both Black and non-Black student-athletes on their lived experiences at PWIs and the meanings of “change” that many Black student-athletes called for in the summer of 2020 because of their lived experiences and the social justice movements that occurred that summer. Eight student-athletes, including six Black student-athletes and two non-Black student-athletes from four different NCAA Division I and II universities, shared their stories through interviews. These athletes were at least freshmen in the year 2019-20, and they represented four sports: baseball, football, soccer, and softball. Five of the athletes were male and three were female.My study started with a research puzzle which is part of narrative inquiry methodology (Clandinin & Connelly, 2000). However, to put the pieces of this research puzzle together, I used a general qualitative research methodology that included methods such as interviews, observations, and document analysis (Patton, 2015). I also participated in online observations and used tweets and other social media posts from Instagram and Facebook to support my findings. This study evolved from the social activism and racial justice movements that occurred in the summer of 2020 when many Black student-athletes called for changes at their respective PWIs, and many used social media to call for these changes.Through data analysis, five themes and five meanings of change emerged. Overall, all my participants believed that changes were needed to improve the experiences and daily lives of Black student-athletes attending PWIs. The New Plantation Model and Critical Race Theory lenses most resonated with the findings of my study. This study contributes to limited research on the meanings of change in student-athlete activism, female student-athletes and White student-athletes’ perceptions and experiences, and overall research on student-athletes’ experiences