REGULATORY EFFECTS OF ACUTE AND CHRONIC ENDURANCE EXERCISE ON NITRIC OXIDE AND REACTIVE OXYGEN SPECIES IN HUMAN CIRCULATING ANGIOGENIC CELLS

This dissertation research comprised three studies examining the effects of acute and chronic endurance exercise on circulating angiogenic cells (CACs). Because the balance between nitric oxide (NO) and reactive oxygen species (ROS) is a critical aspect of the physiological function/dysfunction of CACs, each study determined the effects of exercise on NO-ROS balance within a variety of CAC types. Study #1 demonstrated that regular endurance exercise is associated with greater basal intracellular NO levels in cultured CACs, and that one mechanism underlying this association was increased NADPH oxidase enzyme activity in the sedentary state. Study #2 suggested an association between a sedentary lifestyle and increased nitro-oxidative stress in freshly-isolated CD34+ progenitor cells. Study #3 demonstrated that prior exercise attenuates high-fat meal induced-increases in mitochondrial-derived intracellular ROS in CD31+ CACs. Overall, it is concluded that acute and chronic endurance exercise enhance intracellular NO and ROS dynamics in CACs

Revisiting the vortex-core tunnelling spectroscopy in YBa2_2Cu3_3O7−δ_{7-\delta}

The observation by scanning tunnelling spectroscopy (STS) of Abrikosov vortex cores in the high-temperature superconductor YBa$_2$Cu$_3$O$_{7-\delta}$ (Y123) has revealed a robust pair of electron-hole symmetric states at finite subgap energy. Their interpretation remains an open question because theory predicts a different signature in the vortex cores, characterised by a strong zero-bias conductance peak. We present STS data on very homogeneous Y123 at 0.4 K revealing that the subgap features do not belong to vortices: they are actually observed everywhere along the surface with high spatial and energy reproducibility, even in the absence of magnetic field. Detailed analysis and modelling show that these states remain unpaired in the superconducting phase and belong to an incoherent channel which contributes to the tunnelling signal in parallel with the superconducting density of states.Comment: Final version with supplementary materia

Effects of Prior Acute Exercise on Circulating Cytokine Concentration Responses to a High-fat Meal

High-fat meal consumption alters the circulating cytokine profile and contributes to cardiometabolic diseases. A prior bout of exercise can ameliorate the triglyceride response to a high-fat meal, but the interactive effects of exercise and high-fat meals on cytokines that mediate cardiometabolic risk are not fully understood. We investigated the effects of prior exercise on the responses of circulating tumor necrosis factor-a (TNF-a), interleukin-6 (IL-6), IL-8, leptin, retinol-binding protein 4 (RBP4), vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFlt-1) to a high-fat meal. Ten healthy men were studied before and 4 h after ingestion of a high-fat meal either with or without ~50 min of endurance exercise at 70% of VO2 max on the preceding day. In response to the high-fat meal, lower leptin and higher VEGF, bFGF, IL-6, and IL-8 concentrations were evident (P \u3c 0.05 for all). There was no effect of the high-fat meal on PlGF, TNF-a, or RBP4 concentrations. We found lower leptin concentrations with prior exercise (P \u3c 0.05) and interactive effects of prior exercise and the high-fat meal on sFlt-1 (P \u3c 0.05). The high-fat meal increased IL-6 by 59% without prior exercise and 218% with prior exercise (P \u3c 0.05). In conclusion, a prior bout of endurance exercise does not affect all high-fat meal–induced changes in circulating cytokines, but does affect fasting or postprandial concentrations of IL-6, leptin, and sFlt-1. These data may reflect a salutary effect of prior exercise on metabolic responses to a high-fat meal

Metabolic response during high-intensity interval exercise and resting vascular and mitochondrial function in CrossFit participants

High-intensity functional training (HIFT) can play a major role in preventing cardiometabolic disease. The majority of HIFT interventions incorporate CrossFit (CF) training. We measured aerobic capacity, metabolic response during high-intensity interval exercise (HIIE), resting mitochondrial oxidative capacity, and resting vascular function in adults who participated in CF training (> one year) vs. a sedentary group completing one year (SED). Twenty-one participants were recruited (CF n = 13 vs. SED n = 8). CF participants had a 33.0% greater relative VO2 peak (p.200). CF participants had greater mitochondrial oxidative capacity (p=.014). There were no differences in large artery function, but CF participants had greater baseline arterial diameter (p=.004) and faster reperfusion following arterial occlusion (p<.05). These data support HIFT programs’ effectiveness in improving fitness, weight status, and metabolic, mitochondrial, and vascular function

Size of the protein-protein energy funnel in crowded environment

Association of proteins to a significant extent is determined by their geometric complementarity. Large-scale recognition factors, which directly relate to the funnel-like intermolecular energy landscape, provide important insights into the basic rules of protein recognition. Previously, we showed that simple energy functions and coarse-grained models reveal major characteristics of the energy landscape. As new computational approaches increasingly address structural modeling of a whole cell at the molecular level, it becomes important to account for the crowded environment inside the cell. The crowded environment drastically changes protein recognition properties, and thus significantly alters the underlying energy landscape. In this study, we addressed the effect of crowding on the protein binding funnel, focusing on the size of the funnel. As crowders occupy the funnel volume, they make it less accessible to the ligands. Thus, the funnel size, which can be defined by ligand occupancy, is generally reduced with the increase of the crowders concentration. This study quantifies this reduction for different concentration of crowders and correlates this dependence with the structural details of the interacting proteins. The results provide a better understanding of the rules of protein association in the crowded environment

Proposing the Affect-Trust Infusion Model (ATIM) to Explain and Predict the Influence of High- and Low-Affect Infusion on Web Vendor Trust

Trust is just as essential to online business as it is to offline transactions but can be more difficult to achieve-especially for newer websites with unknown web vendors. Research on web-based trust development explains that web vendor trust can be created by both cognitive and affective (e.g., emotion-based) influences. But under what circumstances will emotion or cognition be more dominate in trust establishment? Theory-based answers to these questions can help online web vendors design better websites that account for unleveraged factors that will increase trust in the web vendor. To this end, we use the Affect Infusion Model and trust transference to propose the Affect-Trust Infusion Model (ATIM) that explains and predicts how and when cognition, through perceived website performance (PwP), and positive emotion (PEmo) each influence web vendor trust. ATIM explains the underlying causal mechanisms that determine the degree of affect infusion and the subsequent processing strategy that a user adopts when interacting with a new website. Under high-affect infusion, PEmo acts as a mediator between PwP and vendor trust; under low-affect infusion, PwP primarily impacts trust and PEmo is dis-intermediated. We review two distinct, rigorously validated experiments that empirically support ATIM. To further extend the contributions of ATIM, we demonstrate how use of specific contextual features-rooted in theory and that drive one\u27s choice of affect infusion and cognitive processing-can be leveraged into a methodology that we propose to further enhance user-centered design (UCD). We further detail several exciting research opportunities that can leverage ATIM

Stories in Song : Voice Faculty Recital

The talented members of the KSU voice faculty present a special recital with the works of Britten, Schubert, and Schumann. Featured Faculty artists include: Todd Wedge, Heather Witt, Jana Young, and Dr.s Nathan Munson and Eric Jenkins.https://digitalcommons.kennesaw.edu/musicprograms/2307/thumbnail.jp

Faculty Recital: Twentieth-Century Songs of the British Isles

The talented members of the KSU voice faculty present an evening of 20th-century art songs of the British Isles featuring works by Ralph Vaughan Williams, Arnold Cooke, and Cecil Armstrong Gibbs. This performance includes soprano Jana Young, tenors Todd Wedge and Nathan Munson, clarinetist John Warren, pianist Eric Jenkins, and commentary by Dr. Edward Eanes, KSU professor of music history.https://digitalcommons.kennesaw.edu/musicprograms/2165/thumbnail.jp

Docking-based long timescale simulation of cell-size protein systems at atomic resolution

Computational methodologies are increasingly addressing modeling of the whole cell at the molecular level. Proteins and their interactions are the key component of cellular processes. Techniques for modeling protein interactions, thus far, have included protein docking and molecular simulation. The latter approaches account for the dynamics of the interactions but are relatively slow, if carried out at all-atom resolution, or are significantly coarse grained. Protein docking algorithms are far more efficient in sampling spatial coordinates. However, they do not account for the kinetics of the association (i.e., they do not involve the time coordinate). Our proof-of-concept study bridges the two modeling approaches, developing an approach that can reach unprecedented simulation timescales at all-atom resolution. The global intermolecular energy landscape of a large system of proteins was mapped by the pairwise fast Fourier transform docking and sampled in space and time by Monte Carlo simulations. The simulation protocol was parametrized on existing data and validated on a number of observations from experiments and molecular dynamics simulations. The simulation protocol performed consistently across very different systems of proteins at different protein concentrations. It recapitulated data on the previously observed protein diffusion rates and aggregation. The speed of calculation allows reaching second-long trajectories of protein systems that approach the size of the cells, at atomic resolution