Open Research Oklahoma (Oklahoma State Univ.)
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4-H Home Demonstration: Ninth year (advanced)
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
Accumulation of maternal and prenatal stress on immune function, stress response, and microbiome
No full textExposure to maternal cortisol during gestation can induce fetal programming, affecting progeny well-being. Despite advancements in the swine industry, stress among pregnant gilts and sows remains prevalent, with research highlighting its effects on offspring immune function and stress responses. However, the influence of stress timing and its long-term effects, particularly during progeny adulthood and pregnancy, remains poorly understood in pigs compared to humans.This dissertation explores how maternal stress, particularly its timing, affects progeny immune and stress responses. The first chapter describes the optimization of a psychological stress model to induce chronic stress through oral administration of synthetic cortisol, effectively elevating maternal cortisol levels in early, mid, and late gestation sows. Although initial findings revealed alterations in progeny immune and stress responses, sample limitations warranted further investigations. Subsequent chapters examined the effects of prenatal stress on hypothalamic gene expression and progeny responses to weaning stress and Adrenocorticotropic hormone (ACTH) challenges. Piglets from mid-gestation hydrocortisone acetate-treated sows (M-HCA) exhibited reduced interleukin-1a gene expression, potentially explaining altered immune responses, while late-gestation HCA-born offspring (L-HCA) showed reduced expression of stress-axis genes. Finally, the dissertation also assessed the generational effects of prenatal stress. Piglets born to prenatally stressed sows displayed distinct immune changes, particularly when their mothers experienced no pregnancy stress. Up- and down-regulation of immune-related genes were observed, depending on stress timing, with some effects persisting across generations, especially under additional stress during pregnancy. These findings emphasize the need for further research to develop interventions that mitigate prenatal stress impacts. Ultimately, this work highlights the importance of understanding maternal stress and its long-term implications on progeny, as it can significantly impact the health and well-being of breeding and marking animals, thereby influence the sustainability and productivity of the swine industry
Culling the laying flock
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
Effects of light, oxygen diffusion, and 4-hydroxy-2-nonenal on redox stability of beef and porcine myoglobin
No full textRetail light conditions influence consumers’ perception of meat color. Previous studies have shown that lipid and myoglobin oxidation are interrelated. 4-hydroxy-2-nonenal (HNE) is an ɑ-, β-unsaturated aldehyde derived from the oxidation of n–6 polyunsaturated fatty acids. HNE-induced bovine and porcine oxymyoglobin (OxyMb) oxidation is influenced by pH, temperature, and atmospheric oxygen partial pressure. However, limited knowledge is available on the effects of HNE on myoglobin redox stability under light/dark and open/closed systems. Therefore, the objective was to examine the effects of light and dark storage conditions (experiment 1) as well as to compare open and closed systems (experiment 2) on HNE-induced bovine and porcine OxyMb oxidation at 4°C. Bovine and porcine OxyMb (0.650 mM; pH 5.6) was mixed with HNE (4.5 mM), whereas controls received an equal volume of ethanol equivalent to delivering HNE. Following mixing, the samples were incubated at 4°C under a continuous fluorescent light source (1,510 lux) or dark conditions (experiment 1). Metmyoglobin (MetMb) formation was measured spectrophotometrically on days 0, 2, 4, 6, and 8 of incubation (experiment 1). In experiment 2, FireflySci Type 46 semi-micro spectrophotometer cuvette cells with SEPTA closed screw caps were used for open (allowing exposure to atmospheric oxygen) and closed (no diffusion of oxygen from outside) systems. MetMb formation was calculated spectrometrically on days 0, 1, 2, 3, and 4 of incubation. The experiments were replicated three times. The presence of light and HNE increased (P porcine). HNE-induced beef OxyMb oxidation was greater (P < 0.05) in an open system than in a closed system. Bovine myoglobin samples with and without HNE had greater metmyoglobin than porcine myoglobin samples with and without HNE when kept in an open system. These findings indicated the potential impact of retail display conditions on species-specific lipid oxidation-induced meat discoloration
Estimation of the equivalent inertia of grid-forming and grid-following inverter-based resources
No full textAs inverter-based resources (IBRs) become increasingly prevalent in power systems, the dynamic behavior of these systems is evolving due to shifts in system inertia characteristics. With the gradual replacement of synchronous generators by IBRs, the constant inertia traditionally supplied by generators is now being replaced by control-emulated inertia from IBRs. Depending on their control strategies, IBRs may provide time-varying inertial support after disturbances, even when operating with a fixed inertia parameter. This thesis introduces the concept of “equivalent inertia” to quantify the collective inertial response of IBR controls by comparing it to the inertia of a fictitious synchronous generator with an inertial response identical to the IBR. An inertia estimation method is then proposed, based on a swing equation-derived function that utilizes bus measurement data. A key advantage of this method is its applicability to both synchronous generators and IBRs without relying on device-specific mathematical models. Additionally, an accurate estimation indicator is proposed to indicate the estimation accuracy. The proposed method is first validated using synchronous generators and subsequently applied to estimate the inertial support of grid-following and grid-forming IBRs. Finally, these estimations are verified through frequency response simulations conducted on the IEEE 14-bus and NPCC 140-bus systems
Influence of blood flow occlusion on muscle oxygenation profiles during intermittent maximal-effort contractions
No full textLimb blood flow occlusion has a profound and quickly reversible effect on motor unit excitation and fatigue development during intermittent, maximal-effort contractions but its impact on microvascular oxygenation and intra-contraction oxygenation profiles remains unknown. The purpose of this study was to determine the impact of complete circulatory occlusion and contraction-induced vascular compression on muscle oxygenation characteristics during intermittent, maximal-effort contractions. Sixteen participants (8M/8F; 22±3 yrs.) performed intermittent maximal-effort contractions (forearm flexion) for 5-min under control conditions (CON) and with complete limb blood flow occlusion (OCC) followed by immediate reperfusion. OCC was initiated at the start of the test and persisted until maximal-effort torque was 0.05). During CON, contraction significantly decreased oxy-[heme], total-[heme], and StO2 at all timepoints (all, p0.05). Complete circulatory occlusion did not increase deoxy-[heme] during intermittent maximal-effort contractions suggesting no significant reserve in oxygen extraction. Muscle contraction increased deoxy-[heme] only during higher intensities above End-Test Torque, suggesting that End-Test Torque represents the highest intensity at which oxygen delivery is matched to oxygen demand
Soil testing, the right first step toward proper care of your lawn and garden
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
Traceability in the United States food supply
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
Improving mammography screening percentages in overdue women: A tribal medical track quality improvement project
No full textBackground: In Cherokee County, mammography screening percentages are below the overall state and national averages. This is problematic, as adequate and timely mammograms can detect breast cancer at an earlier stage. This quality improvement (QI) project, conducted during a four-week clinical rotation, aimed to increase screening among overdue patients at a Cherokee Nation family medicine clinic and to assess the feasibility of conducting QI studies during short rotations.Methods: During scheduled in-clinic appointments with eligible patients, the medical student (and first author) assigned to the patient’s physician used motivational interviewing (MI) to encourage women to schedule mammograms. Patients’ electronic health records were followed until a completed mammogram appointment was viewed or until December 21, 2023, whichever came first.Results: Only two patients seen during the project timeframe were overdue for screening and one completed screening by the project cutoff date. The other patient indicated she preferred a more “natural” approach and thus never planned to get screened.Conclusions: Targeted motivational interviewing during scheduled in-clinic appointments may increase the likelihood of women obtaining mammogram screening. The project demonstrated the feasibility of conducting QI projects during short rotations, but also identified challenges of reaching targeted patients who may or may not visit the clinic during the rotation
Estimating species richness in an ephemeral system
No full textClimate change-induced alterations in ecosystems can have profound effects on species diversity and ecological dynamics. Cimarron County, Oklahoma has experienced severe droughts since 2011, prompting an investigation into the limited knowledge surrounding terrestrial mammals present within the region. Camera traps are a minimally invasive way to sample terrestrial mammals across a large area. We attached trail cameras to trees or t-posts ~45cm off the ground at 160 opportunistic sites across the county. Cameras were deployed for ~28 days from May-August 2022 and 2024. We conducted a literature review to compile a community species list of 27 animals that had a predicted overlapping range with Cimarron County. Only species with a body mass ≥0.6kg were considered, to ensure accurate detection and identification on camera trap images. We analyzed ~300,000 images from a larger study of black bears in Cimarron County, Oklahoma, and categorized the county into four habitat types: mesa country, cropland, rangeland, and river bottom. Given certain aspects of the land and species behavior, it’s plausible that not every predicted species would appear on camera while occurring in the county. To account for imperfect detection, we collected data on diet preference, activity patterns, and sociality for each of the 27 species from our literature review to use as covariates. We also created a binary covariate of whether the species would be common (1) or rare (0) in the specified habitat type, and ran a single-species occupancy model with each of the covariates placed on detection. We ran the model four separate times to assess species richness in each of the four habitat types. 21 of the 27 species from our species list were detected. Estimated richness (Ѱ) in each habitat type was Ѱ=0.63 for mesa country, Ѱ=0.71 for cropland, Ѱ=0.55 for rangeland, and Ѱ=0.48 for river bottom. Our results can be used to further understand species richness, guiding managers to implement strategies that help mitigate effects of climate change, prioritize conservation efforts, and enhance community species richness and diversity.Natural Resource Ecology and Managemen