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AJUR Volume 16 Issue 1 (June 2019)

DOI for AJUR‘s Volume 15, Issue 4 is

Links to individual manuscripts, abstracts, and keywords are provided below.


p.5. Should high-top or low-top cleats be used when playing baseball?
Margo P. Wohlfeil, Cole R. Neary, Mitchell M. Klocke, Johnny G Mills, Rich C. Calvert, & David S. Senchina
ABSTRACT: There is a shortage of knowledge about how baseball cleat design may impact athletes. The purpose of this experiment was to determine if the height of the baseball cleat affected performance, perception of the cleat, and ankle range-of-motion. Thirteen subjects participated in the study, and each subject performed three drills (base-running, 5:10:5 “pro agility,” and hitting) in both high-top and low-top baseball cleats. Performance time was measured for the first two drills. Perception of comfort, heaviness, shoe climate (heat), stability, and traction were measured for all three drills using 10-cm visual analog scales (VAS). Ankle range-of-motion (dorsiflexion, plantarflexion, eversion, and inversion) was measured using goniometry in both cleats, plus socks-only as baseline control. Shoe height did not significantly affect completion time in either the base-running drill (6.1±0.1 sec. in high-top vs. 6.1±0.1 sec. in low-top) or pro-agility drill (4.8±0.1 sec. in high-top vs. 4.6±0.1 sec. in low-top). There were significant differences in perception of heat (6.4 in high-top vs. 4.6 in low-top; p<.001), stability (6.9 in high-top vs. 5.1 in low-top; p=.001), and heaviness (6.0 in high-top vs. 4.1 in low-top; p<.001), but not in perception of comfort (6.1±2.0 in high-top vs. 6.6±1.5 in low top) or traction (7.3±2.0 in high-top vs. 7.4±1.5 in low-top). There were significant differences between high-top and low-top cleats in plantarflexion (42.5° in high-top vs. 47.5° in low-top; p=.033), eversion (7.9° in high-top vs. 11.3° in low-top; p=.003), and inversion (12.8° in high-top vs. 16.6° in low-top; p=.044), but not dorsiflexion (8.2° in high-top vs. 10.9°). For baseball players concerned about excessive ankle movements during play, these results suggest that using a high-top baseball cleat might reduce ankle range-of-motion without impairing performance or feeling burdensome.
KEYWORDS: Baseball; Cleats; High-Top; Low-Top; Perception; Performance; Range-of-Motion; Shoes

p.15 Transcription of nanos-1 in Zebrafish Embryos is not Affected by Bisphenol A: Evaluated Using Quantitative Real-Time PCR
Bridget Babich, George Roba, Siti Sarah Safura*, Kevin Callahan, & Edward Freeman
ABSTRACT: The presence of primordial germ cells (PGCs) is crucial for proper gonad formation in zebrafish (Danio rerio). The many aspects of PGC migration that allow these cells to reach the proper location at the gonadal ridge include receptors, ligands, germ plasm components, and internal maintenance of PGCs. Any one of these factors could be affected by endocrine-disrupting chemicals (EDCs), which have been shown to alter the directed migration of these cells during early embryonic development. Based on recent research wherein the EDC bisphenol A (BPA) inhibited normal PGC migration, we have used the same dose of BPA to determine the impact of BPA on a gene central to proper germ cell migration. Zebrafish embryos were exposed to BPA, and the levels of the target gene nanos-1 were analyzed using quantitative real-time PCR (q-PCR). The target gene nanos-1 is a critically important germplasm component that allows for survival and proper migration of PGCs. The q-PCR results showed that BPA did not affect the transcription level of nanos-1 in zebrafish embryos.
KEYWORDS: Zebrafish; Zebrafish Embryos; nanos-1; Primordial Germ Cells; PGC Migration; Gonad Development; Endocrine-Disrupting Chemicals; Bisphenol A; Sex Determination

p.23 Investigation of Atmospheric Aerosol Size Distributions from Ground-Based Solar Spectrometer Measurements Synthesized with Satellite Data
Dane T. Kuhr Adam T. Whitten
ABSTRACT: Data collected by a ground-based solar spectrometer at Collegeville, MN, was used to generate Aerosol Optical Depths (AODs) throughout the 2017 calendar year. The AOD data was then visualized at 13 selected wavelengths throughout the year and analyzed in comparison to satellite imagery, upper air charts and backwards trajectories of air masses moving towards Central Minnesota in order to determine key dates of interest that correspond to times before (20170615), during (20170729), and at the conclusion of (20170914) forest fires that burned in British Columbia (BC) during the summer of 2017. The data from these specific days were analyzed further by inputting the maximum and minimum AODs for each day into a Parameter Based Particle Swarm Optimization (PBPSO) algorithm in order to generate bimodal lognormal particle size distributions. The bimodal distributions were chosen because they carry more information about the aerosol loads across the entire spectrum of particle radii. The resulting distributions show an increase in number density and decrease in median radius in the Aitken mode during the BC forest fires and a relatively constant (within uncertainty) number density of accumulation mode particles at daily maximum AODs. Comparing the resulting bimodal lognormal distribution for daily minimum AODs (where evaporation and other diurnal effects are at a minimum) shows an increased number density of Aitken mode particles by two orders of magnitude from pre- to post-forest fires. This measured increase in the number density of smaller radii particles due to forest fires illustrates the PBPSO’s capability of distinguishing variations in atmospheric aerosol particle number size distributions in the Aitken mode based on data collected by the Kipp-Zonen PGS-100 solar spectrometer.
KEYWORDS: Atmospheric Aerosol; Particle Swarm Optimization; Aerosol Optical Depth; Solar Spectrometer; Size Distributions; Forest Fire; Satellite Imagery; Upper Air Charts; Backward Trajectory

p.33 Diol Mediated Tautomerization of Glycine: a DFT Study
Francis Suh, Vanessa Rivera, & Ruben D. Parra
ABSTRACT: The tautomerization of glycine via a triple proton transfer was investigated both in the gas phase and in aqueous solution using the B3LYP/6-31+G(d,p) level of theory. Fully optimized complexes of the neutral and zwitterion forms of glycine with 1,3-propanediol were used for the reactant and product forms, respectively. The hydroxyl groups in the diol are conveniently oriented for glycine tautomerization through a concerted triple proton transfer facilitated by a network of three hydrogen bonds: N-H…O-H…O-H…O=C. The activation energy for the zwitterion à neutral process increases in solution. Also, the diol-glycine complex favors the neutral over the zwitterion form in a vacuum, but the opposite is true in solution. For comparative purposes, the tautomerization of glycine via a three-proton transfer mediated by two molecules of water was also examined. The results are qualitatively similar, albeit with activation energies that are smaller to those found in the corresponding diol-mediated tautomerization.
KEYWORDS: Glycine; zwitterion, diol-mediated tautomerization; water-mediated tautomerization

p.41 Psychological Constructs as Predictors of Strength Gains in a Strength Training Course
Kathrine Hadley & Joanna Morrissey
ABSTRACT: Strength training has many benefits, both affective and physical health-related. However, little research has been done on the psychological constructs that play an important role in exercise adherence, maintenance, and outcomes regarding strength training specifically. The purpose of this study was to examine self-efficacy (SE), perceived competence (PC), and outcome expectancy (OE), several of the key psychological constructs, as predictors of strength gains in a strength training course. It was hypothesized that the changes in participants’ measures of SE, PC, and OE from baseline to post-training would predict participants’ actual strength gains, but not the levels of SE, PC, and OE at baseline and post-training independently. Participants (n=20; 50% 20-21 years old, 40% 22-24 years old, 10% 25 years or older; 60% female, 40% male; 45% Caucasian, 30% Hispanic/Latino, 20% multiracial, 5% Asian/Pacific Islander) in a 15-week strength training technique (STT) course completed a battery of psychological questionnaires assessing SE, PC, and OE in addition to fitness tests consisting of a vertical jump test, an estimated one repetition maximum bench press and a back squat at baseline, mid- and post-training. One-way repeated measures ANOVA was used to examine differences in SE, PC, and OE at baseline, mid-, and post-training. Spearman correlation and multiple regression analyses were used to determine the predictive specificity of baseline, mid-, post-training levels, and changes in SE, PC, and OE on strength gains. ANOVA results show a significant time effect, as there was a significant increase in all three variables over time, suggesting that course participation increased students’ SE, OE, and PC about strength training. Baseline scores, post-training scores, and changes in SE, PC, and OE were not significant predictors of changes in strength or power scores. These results suggest that while an instructor-led STT course may increase SE, OE, and PC for individuals with varying strength training experience and positively influence college students’ well-being, these psychological constructs may not predict strength gains. Future research should examine possible predictive factors for strength training outcomes in larger, more heterogeneous populations.
KEYWORDS: StrengthTraining; Self-Efficacy; Perceived Competence; Outcome Expectancy; Psychological Constructs; Kinesiology; Strength and Conditioning; Resistance Training

p.49 Modeling Networks of Evolving Populations
Sean Elliott
ABSTRACT: The goal of this research is to devise a method of differential equation based modeling of evolution that can scale up to capture complex dynamics by enabling the inclusion of many—potentially thousands—of biological characteristics. Towards that goal, a mathematical model for evolution based on the well-established Fisher-Eigen process is built with a unique and efficient structure. The Fisher-Eigen partial differential equation (PDE) describes the evolution of a probability density function representing the distribution of a population over a phenotype space. This equation depends on the choice of a fitness function representing the likelihood of reproductive success at each point in the phenotype space. The Fisher-Eigen model has been studied analytically for simple fitness functions, but in general no analytic solution is known. Furthermore, with traditional numerical methods, the equation becomes exponentially complex to simulate as the dimensionality of the problem expands to include more phenotypes. For this research, a network model is synthesized and a set of ordinary differential equations (ODEs) is extracted based on the Fisher-Eigen PDE to describe the dynamic behavior of the system. It is demonstrated that, when juxtaposed with full numerical PDE simulations, this ODE model finds well-matched transient and precise equilibrium solutions. This prototype method makes modeling of high-dimensional data possible, allowing researchers to examine and even predict complex dynamic behavior based on a snapshot of a population.
KEYWORDS: Evolutionary Modeling; Mathematical Biology; Network Dynamics; Ordinary Differential Equations; Partial Differential Equations; Fisher-Eigen model; Phenotype; Fitness Function

p 65 Assessing the Use of Cooking Demonstrations on Healthy Eating Barriers in City Bus Riders
Julianne Evans & Diana Cuy Castellanos
ABSTRACT: People living in food-insecure households may experience access-related barriers to preparing and consuming fresh produce, such as high cost and limited local availability. Nutrition interventions that incorporate improved access play a decisive role in overcoming these barriers. The urban bus hub fresh produce market was developed to address food insecurity in Dayton, Ohio. Over four months, dietetic students from a four-year, private, mid-western university provided cooking demonstrations and recipe distribution nutrition interventions at the market. We used a quasi-experimental study design to determine the effectiveness of the cooking demonstration and recipe distribution intervention on access-related barriers at the urban bus hub fresh produce market. A ten-item quantitative questionnaire, on a Likert-type scale from 1-10, with 10 as a more favorable response, and four open-ended questions were administered once to each consented participant (N=33) to examine the recipe effectives and explore the access-related barriers. T-tests were used to examine barriers from the questionnaire and determine differences between participants who made the recipe and participants who did not make the recipe. Results of the t-test indicate no significant difference between those who made the recipe and those who did not make the recipe (p>0.05). Mean scores for affordability, acceptability, accommodation, availability, and accessibility on the then ten-item questionnaire were 7.83, 8.44, 9.19, 9.38, and 8.44, respectively. Thematic analysis results were used to examine the barriers from the open-ended questions further and revealed that affordability and time barriers were present in the priority population. Lack of money, job loss, and unemployment were identified as contributing to affordability barriers and transportation and time to shop, prepare, or cook produce, and to find mealtimes were identified as contributing to time barriers. Nutrition professionals should continue developing appropriate interventions for affordability and time barriers in convenient locations for participants to encourage fruit and vegetable consumption and to establish evidence-based practices.
KEYWORDS: Cooking demonstrations; food insecurity; produce consumption barriers; nutrition intervention; food stand; recipe distribution; bus hub