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Sickle Cell Disease Increases Glycolytic Muscle Fiber Proportions while Impairing Muscular Strength in Mice
No full textThe Effect of Mental Training on Psychological Hardiness and Selected Personality Traits among Adolescent Male Volleyball Players
No full textInternational Journal of Exercise Science 18(4): 1186-1198, 2025. https://doi.org/10.70252/MQUH7716 This study was to examine the effect of a mental training program, including a combination of autogenic training and imagery, on a number of mental skills and on the development of personality traits - psychological hardiness as well as conscientiousness, openness to experience, and neuroticism - in Adolescent male volleyball players. 60 adolescent male volleyball players (aged 15–17) participated in a two-group, pretest-posttest design. The experimental group (n = 30) completed 8-week mental skills training program, including imagery, self-talk, attention control, and relaxation, while the control group (n = 30) followed regular training. Psychological hardiness and selected personality traits were measured pre- and post-intervention using validated scales, and data were analyzed with mixed-design ANOVA and effect sizes. result show significant improvements in psychological hardiness (commitment, control) and personality traits (conscientiousness, openness to experience) in the experimental group (p \u3c 0.01), with modest decreases in neuroticism. Large effect sizes (Cohen’s d = 0.57–1.19; partial η² = 0.07–0.37) highlight the practical impact of the intervention compared to the control group, which showed minimal changes. Structured mental skills training significantly enhanced psychological hardiness, conscientiousness, and openness, modestly reduced neuroticism, and demonstrated practical impact, supporting its integration into adolescent male volleyball players’ holistic development programs
DPICS, PCIT, assessment, child
No full textThe current study focuses on experiences of microaggressions and the sense of belongingness among minoritized students in school psychology graduate programs. This study followed previous research that uncovered racially toxic environments in clinical psychology programs and discussed ideas to ameliorate recruitment and retention efforts (Galen et al., 2023). Participants (n = 95) in this study consisted of graduate students in school psychology programs at the master’s, specialist (e.g., Ed.S., C.A.S.), and doctoral level in the U.S., who completed an online survey about their perceptions of recruitment efforts, sense of belonging and experiences of microaggression. The findings revealed that racially minoritized graduate students reported more negative perceptions of recruitment efforts, higher levels of experiencing microaggressions, and a decreased sense of belonging compared to White/Caucasian graduate students. Subtle differences in various aspects of student and program experiences were discussed based on the findings. Continued efforts in research and program improvements will hopefully help school psychology training programs create an environment where all students can feel safe, welcomed, and appreciated
UNDERGRADUATE STUDENTS’ PERCEPTIONS OF UNIVERSITY LIBRARIES’ SERVICES, RESOURCES, AND PHYSICAL SPACES: A DESCRIPTIVE ANALYSIS
Get PDFUnderstanding undergraduate students\u27 perceptions regarding university libraries’ services, resources, and physical space allows library leadership to improve student support. The purpose of this needs assessment using cross-sectional survey data of undergraduate students (N = 1733) was to examine how students use the libraries, how they perceive their ability to use resources, services, and physical spaces, and the relationship between use and perception to better understand satisfaction levels with everything academic libraries offer. Interviews with library leadership (N = 3) offer insight into how data received from the needs assessment were utilized to improve academic libraries and highlight the importance of stakeholder values in academic libraries’ support services. Findings indicate that the academic libraries in this study need to create and develop a supportive physical space that supports undergraduate students and improves access to services and resources provided. Implications for this study included increased usage and academic support for undergraduates if new spaces and services were developed
DERIVING THE EFFICIENCY OF ELECTRON ACCELERATION WITHIN CURRENT SHEETS IN THE MAY 8TH, 2021 SOLAR FLARE USING A CENTROID ANALYSIS METHOD ON STIX X-RAY DATA
Get PDFSolar flares are powerful explosions that take place on the Sun, equivalent to a billion atomic bombs, and eject billions of tons of material into space. Flares that reach Earth can disrupt power grids and damage satellite communication systems, presenting challenges for our national security. Studying solar flares is crucial to better understand and prepare for these events.
During a solar flare, electrons are accelerated into the surrounding plasma. The interaction between electrons and heavier particles within the plasma causes the emission of powerful X-rays. Studying X-rays from solar flares can, therefore, provide insight into the accelerated electrons that produce them, allowing for a deeper understanding of solar flare processes.
The Spectrometer Telescope for Imaging X-rays (STIX) instrument onboard the Solar Orbiter mission observes the X-ray emission from solar flares. Using an indirect imaging technique, where we invert the spatial Fourier transform of the source, the X-ray data recorded by STIX can be used to reconstruct an X-ray image of the solar flare. Alternatively, we can get the Fourier transform of the electron flux by performing a spectral inversion on the Fourier transform in count space, and then the inverse Fourier transform provides images of the electron flux.
Electron flux images show the location and energy of electrons within a solar flare. Each image is proportional to the product of the density of accelerated electrons at a specified energy and the density of the plasma into which they are injected. Evaluating these densities separately could provide insight into the processes of a solar flare, but the electron maps contain information only on their product. To overcome this problem, a centroid analysis on the electron maps was performed to evaluate the target density separately.
Specifically, a centroid analysis method performed on the electron maps for the May 8th, 2021 solar flare produced an average target density of 5.8 × 1011 cm−3. Using this, together with the observed electron spectrum, the average density of accelerated electrons was shown to be 1.2 × 105 cm−3. Then, using a simple 1-D acceleration model, the ratio between the accelerated electron density and the target density was used to find an electric field of 7 × 10−5 V cm−1 and an average accelerated electron energy of 42 keV.
The energy output of the May 8th, 2021 solar flare was approximately 1030 erg. This energy value was then used to derive a magnetic field of B = 120 G. The electric and magnetic fields are then used to find the average thickness of a current sheet d = 3600 cm. From this length value and the dissipation timescale (τ = 60 s), the conductivity of the plasma was found to be σ = 4 × 1014 s−1, with a magnetic diffusivity of η = 2 × 105 cm2 s−1. Thus, the solar flare had an increased diffusivity and decreased conductivity compared to coronal plasma (η = 300 cm2 s−1 and σ = 2×1017 s−1). The energy stored between the approaching fields is on the order of 1024 erg. It follows that the observed energy of the flare requires approximately 300,000 current sheets
Enhancing Mental Toughness and Strength and Conditioning Performance in Collegiate Athletes Through Pressure Training
Get PDFInternational Journal of Exercise Science 18(4): 456-469, 2025. This study is the first to investigate the role of mental toughness (MT) in predicting strength and conditioning (S&C) performance outcomes and the impact of pressure training (PT) on MT development among NCAA athletes. A women’s Division I field hockey team (n = 15) participated in five 1-hour sessions focused on psychological skills training to enhance MT, followed by two S&C sessions under PT conditions. Using the Mental Toughness Index, MT was assessed after the workshops/before PT and following PT. Regression analysis revealed that pre-PT MT scores predicted S&C performance outcomes during PT sessions (F(1, 16) = 4.67, p = .0499, 95% CI [0.154, 0.803]), with a positive correlation between MT scores and performance (R2 = 0.26, β = 0.07, 95% CI [0.00, 0.15]). A paired samples t-test revealed a significant increase in MT scores post-PT (t(12) = -3.34, p = .006, d = 0.93, 95% CI [-3.31, -0.69]), suggesting PT effectively enhances MT. PT sessions incorporated relevant-to-the-team demands and consequences, incidentally leading to increased athlete engagement and performance intensity. Overall, the findings demonstrate the relevance of PT as an innovative and practical tool for S&C coaches, offering initial evidence of its capability to enhance athlete development and optimize performance under high-stake conditions with strong ecological validity due to its application in real-world training environments. Future research should explore the longitudinal application of PT across larger samples, diverse sports, and its long-term effects on performance outcomes
Sport participation positively associated with balance confidence and well-being in transtibial amputees
Get PDFInternational Journal of Exercise Science 17(5): 1663-1678, 2024. Transtibial amputation (TTA) is the removal of the lower leg often resulting in pain, mental health issues, and a more sedentary lifestyle that lacks physical activity (PA). Low balance confidence and other factors related to the physical and psychosocial adaptation to amputation could contribute to why people with TTA actively avoid PA. Studies have investigated lower extremity amputations and barriers to PA in general, but none have focused solely on transtibial amputation and its relationship with PA participation and avoidance habits. To address this issue, 21 participants with TTA (14 male, 6 female, and 1 non-binary) shared their experiences through an online survey. Relationships between variables were examined with Spearman and Pearson correlations. Results revealed a positive relationship, with a moderate effect size between balance confidence and the sport index scale and multiple other correlations between the physical and psychosocial adaptation to TTA and PA participation and avoidance. Those who participate in sport following TTA seem to show a positive association with social adjustment and balance confidence. In addition, adaptations such as adjusting to new limitations and activity restrictions, as well as satisfaction with the function of the prosthesis, are also related to PA participation and avoidance. This study supports the premise that participating in PA, specifically sport, has physical and psychosocial benefits that cannot be undervalued. Insights drawn from this study lend support to evidence-based practices of rehabilitation programs for people with TTA that focus on balance confidence training. If those with TTA are interested in sports, balance confidence training via sport-specific training could further facilitate a positive adaptation following TTA
The Relationship Between Traditional Performance Measures Countermovement Jump Testing in Youth Female Soccer Athletes
Get PDFJump testing using electronic force plates has gained interest in sport and rehabilitation settings for evaluating performance and recovery across all levels, from youth to professional. While these devices produce extensive data on jump metrics, little information exists on how they relate to traditional sport performance measures used in athletic or therapy settings for youth athletes. PURPOSE: Examine the relationship between countermovement jump (CMJ) testing measures assessed via the VALD ForceDecks Lite® force plate system and common sport performance tests associated with lower extremity strength, power, agility, and injury risk in elite youth soccer athletes. METHODS: All procedures for this investigation were approved by the institutional review board. Seventy-four female elite soccer athletes (Age: 101yr) were recruited from the surrounding area and provided informed consent before participation. All athletes were then subjected to a battery of traditional sport assessments performed in a randomized order: Pro-agility 20-yard shuttle test time, Y-balance test, knee flexion (hamstring) /extension (quadricep) strength testing via dynamometry, single leg hop distance, and single leg triple hop distance. All athletes also underwent CMJ testing on the ForceDecks Lite system, assessing force, power, rate of force development, limb asymmetry, and velocity for overall jump performance, as well as for the eccentric, concentric, and landing phases. Pearson correlation analysis was used to evaluate the relationship between force plate measures and traditional performance tests. Significance was set at PRESULTS: Several CMJ metrics were observed to be correlated with one or more of the traditional test measures (P 97 N) was observed to be correlated with all traditional test measures: hamstring (r=0.506) and quadricep (r=0.458) strength (P 151 W) and peak jump power (Avg. 1643 275 W) were observed to be correlated with hamstring (r=0.475, 0.441) and quadricep strength (r=0.450, 0.453), pro agility test (r=-0.346, -0.410), single leg (r=0.246, 0.253), and triple hop distance (r=0.252, 0.259) (P1834 N/s) was found to be correlated with hamstring (r=0.329) and quadricep strength (r=0.334), and the pro agility test (r=-0.271) (P0.19 m/s) was observed to be correlated with the pro agility test (r=-0.570) as well (PCONCLUSION: In youth female soccer athletes, several traditional performance metrics commonly performed in sport and clinic settings correlate with CMJ force plate testing; particularly metrics associated with the concentric component of the CMJ. These findings may aid coaches, athletic trainers, physical therapists, and clinicians to better understand how force plate testing may directly relate to performance parameters that they may be more familiar with. Given the identified associations and the rapid/mobile nature of on-site force plate testing, tests such as the CMJ may have specific advantages when frequent testing is desired for athlete monitoring