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SEASONAL VARIATION IN ROTIFER OCCUPANCY WITHIN FRULLANIA EBORACENSIS LOBULES: ILLUMINATING A SYMBIOTIC RELATIONSHIP BETWEEN TWO OVERLOOKED SPECIES
No full textBdelloid rotifers are well documented as inhabitants within lobules of the widely distributed epiphytic liverwort, Frullania eboracensis. This research provides a detailed description of rotifer occupancy within lobules of F. eboracensis and tests the hypothesis that rotifer excrement might be a source of nutrients for F. eboracensis. My goals were to 1) investigate how rotifers are distributed among F. eboracensis, 2) how rotifer abundance is impacted by seasonality, and 3) use quantum dot (QD) labeled Escherichia coli as a food source for rotifers and track the QDs from bacteria to rotifer to F. eboracensis. Frullania eboracensis samples were collected in fall 2014 to fall 2016. QD experiments were conducted in fall 2023. The results showed rotifers had a much higher probability of occupancy for the first 5-6 lobules, slowly declining thereafter. Rotifer abundance was stable across the 1.5-year period, but there was a slight increase in density during the late fall and early winter. QD fluorescence was observed within the stomach cavity and intestine of rotifers and F. eboracensis showed evidence of rotifer-derived QD uptake from rotifer feces. The findings in this study support the hypothesis that F. eboracensis utilizes nutrients from rotifer feces and is the first study to document transfer of QDs from bacteria to animal to liverwort
Strategic planning in higher education: perceptions of faculty and administrators at public institutions.
Get PDFOver the past several decades, strategic planning has become ubiquitous in higher education. Yet, there are varying perceptions of its overall value. Perceptions of value are critically important as they can influence the effectiveness and breadth of participation in the strategic planning process, and such participation is widely held to be critical for success. We investigated these issues using an on-line survey distributed to faculty, chairs, and deans at public colleges and universities in the United States. We found that, compared to both faculty and chairs, deans had a more positive assessment of whether the benefits of the process were greater than the costs and were significantly more familiar with strategic plans. On the other hand, faculty indicated strategic plans had less effect on how they do their jobs, while chairs held a negative view as to whether the process led to meaningful evaluation and change. Interestingly, there were no significant differences between responses from baccalaureate, master’s, and doctoral institutions. Although shared governance in the strategic planning process is widely endorsed, our work suggests that new approaches may be necessary to achieve the goal of an effective strategic planning process
The Mongolian Remodeling and the structure of Anoplocephalid cestode diversity
Get PDFEcological disruption plays an important role in structuring diversity of flora, fauna, and their parasites. At the end of the Eocene, climatic change across Asia resulted in a faunal turnover (the Mongolian Remodeling) as rodents diversified and larger mammals declined. Throughout the Oligocene, the landscape in Asia was characterized by episodic climatic and landscape changes resulting in pulses of rodent diversification. The role of historical ecological disruption in Central Asia in structuring the diversity of parasites of small rodents has not been thoroughly investigated. The hyper-diverse Paranoplocephala species complex (family: Anoplocephalidae) infect rodents throughout the Holarctic and present an opportunity to investigate the consequences of ecological disruption on the diversity of parasites. Here, I use whole mitogenome sequencing to produce a well-resolved phylogeny showing relationships within the Paranoplocephala species complex. I test the hypotheses that the Mongolian Remodeling initiated diversification and subsequent recurrent episodes of climatic change increased the tempo of diversification within this parasite assemblage. Using mitochondrial genome sequencing, I built the most robust phylogenetic tree of seven known species and eight previously unknown lineages. A clock calibration estimate put the temporal origin of the Paranoplocephala species complex approximately 42 MYA and lineage through time tests showed more diversification occurred in deeper time. Results indicated multiple trans-Beringian dispersal events and numerous host-colonization events, consistent with ecological disruption playing an important role in structuring parasite diversity
NEUROMUSCULAR ELECTRICAL STIMULATION IN COMPARISON TO HEAT THERAPY AS A MODALITY AFTER EXERCISE-INDUCED MUSCLE FATIGUE
Get PDFIncreasing blood flow to exercised areas expedites metabolite removal, aiding quicker recovery and preventing injury during return to exercise. However, the effectiveness of different recovery modalities remains unclear. The purpose of the study is to evaluate the efficacy of neuromuscular electrical stimulation (NMES) and heat therapy (HT) as recovery modalities after inducing fatigue with maximal exercise in active individuals. The study involved 56 participants who performed a fatiguing exercise before the intervention. They then either rested (control group) or received one of three treatments: HT, NMES, or NMES+HT for 15 minutes. Afterward, they performed another bout of fatiguing exercise. Outcomes included ground reaction force (GRFz) and ratings of perceived exertion (RPE) immediately after fatiguing exercise. An ANCOVA was used to control for pre-test values as a covariate. No statistically significant effect x time or intervention were observed after controlling for peak total GRFz (pre) at p=0.16. RPE scores also did not reveal any statistical significance (p\u3e0.05). Results showed that pre-test GRFz values (mean ± SD) were 2248.7 ± 788.19 for the control group, 2526.52 ± 703.65 for HT, 2368.86 ± 837.72 for NMES, and 2196.39 ± 560.62 for NMES+HT. Post-test values were 2051.76 ± 783.67 for the control group, 2434.29 ± 839.67 for HT, 2400.82 ± 737.62 for NMES, and 2269.94 ± 699.23 for NMES+HT. Despite the lack of statistical significance, NMES and/or HT showed potential for enhancing recovery compared to the control group, particularly in peak GRFz, indicating a potential increase in recovery efficacy for improved performance and injury prevention
Transcranial Direct Current Stimulation of the Dorsolateral Prefrontal Cortex Does Not Improve Handgrip Time-to-Failure or Alter Central or Peripheral Hemodynamics
Get PDFAge-related deviations to the neuromuscular system negatively impact motor function and performance. Transcranial direct current stimulation (tDCS) has been linked to improvements in the neuromuscular system. The purpose of this study was to determine if tDCS delivered to the dorsolateral prefrontal cortex (DLPFC) would improve handgrip time-to-failure in adults 60 years old and older. Twenty-five participants completed five maximal voluntary contractions, followed by 20-minutes of a-tDCS or SHAM conditions. Next, participants completed a handgrip time-to-failure task by maximally squeezing an electronic handgrip dynamometer until they could no longer maintain 50% of their maximal voluntary contraction. Pairwise t-test revealed a non-significant difference between tDCS and SHAM conditions on handgrip time-to- failure t(24 ) = 0.254, p = 0.401. Separate 2 x 5 ANOVA’s revealed no main effect of condition on changes in baseline HbO, HbR, and HbT for DLPFC and muscle hemodynamics (all p \u3e 0.05). A linear mixed-effects model revealed no significant main effect of condition on recovery MVC (p \u3e 0.05). This study provides evidence tDCS does not improve HGTTF in older adults, adding contrastingevidence regarding the effects of an acute session of tDCS. Further research is needed to confirm the ergogenic effects of acute tDCS
A SYSTEM FOR AUTOMATIC AND FAST GYMNASTICS POSE ESTIMATION AND KEY FRAME IDENTIFICATION
Get PDFIn artistic gymnastics, performance analysis tools that provide immediate feedback to athletes and coaches are key to optimizing performance. Therefore, we developed a system that provides direct video feedback and automatically identifies key frames relevant to achieve high performance. This system estimates the gymnast’s two-dimensional (2D) and three-dimensional pose from a single-view video and uses a long short-term memory (LSTM) network to identify key frames, in which contact with the ground or an apparatus starts or ends. We compared three 2D pose estimation algorithms and found that MoveNet yielded the highest accuracy, being able to detect 84% of the joints accurately. The LSTM network detected the key frames with a 97% F1 score. In conclusion, our system provides direct video feedback to gymnasts and coaches relevant performance parameters
EFFECTS OF FATIGUE AND DIFFERENT CRIMP SIZES ON MUSCLE SYNERGIES DURING DEAD HANGS: A PILOT STUDY ON CLIMBERS
Get PDFThe aim of this pilot study was to investigate the impact of different hold sizes on the motor control of upper body muscles during intermittent dead hangs. Four elite-level climbers (3 females, 1 male, 25.5 ± 6.8 years, 166.0 ± 7.8 cm height, 59.0 ± 8.8 kg weight, and 21.0 ± 1.4 IRCRA scale climbing grade ability) performed body-weight intermittent isometric dead hangs (7:3 s work-to-relief ratio) until failure, using a half-crimp position, onto edges of 10- and 30-mm. Muscle activations of upper limb muscles were recorded with surface electromyography electrodes and then used to calculate muscle synergies and forces were measured on an instrumented hang board. Results showed that two synergies were mainly used during the intermittent test: Synergy 1 with a higher contribution of the hand muscles, and Synergy 2 with higher contributions of the arm and trunk muscles. A cross-correlation analysis showed high correlations of both synergies between each crimp size (Synergy 1 and 2 at 10 and 30 mm had r = 0.98 and r = 0.89, respectively). A detailed correlation analysis throughout the whole time series indicated close to fatigue, Synergy 1 decreases activation while Synergy 2 increases, especially in the second half of the dead hang cycle. Our findings provide a nuanced understanding of upper body muscle involvement in intermittent dead hangs, informing future research on motor control and fatigue in climbing-related activities
EFFECTS OF SHORT VS. LONG WARM-UP PROTOCOLS ON BIOMECHANICS AND PERFORMANCE IN A 50- M SWIMMING TRIAL
Get PDFThe purpose of this study was to compare the effect of two warm-up, protocols differing in volume, on biomechanical and performance parameters in a simulated 50m freestyle swimming trial. Twelve well-trained male swimmers of regional and national levels performed, in random order, two 50-m time trials on separate days, after a 600m, 12 min warm-up (Short Warm-Up, SWU) or a 1200m, 24 min warm-up (Long Warm-Up, LWU) protocols in random order. The results show that only the SWU warm-up protocol significantly improved swimming performance, although there is no difference between protocols in most kinematic parameters
NEUROMUSCULAR FUNCTION DURING MAXIMUM INTENSITY SIDESTEP-CUTTING MANOEUVRE: EXPLORING THE INFLUENCE OF ANTICIPATION AND PRIOR ACL INJURY
Get PDFThis study focuses on understanding the consequences of Anterior Cruciate Ligament (ACL) injuries and their rehabilitation effectiveness by comparing muscle forces in planned and unplanned movements between healthy and reconstructed ACL limbs. 3D motion and ground reaction force data were collected from high-performance athletes who underwent reconstructive surgery and performed a sidestep cut. Results showed lower limbs with a reconstructed ACL had lower contributions of the vasti to anterior accelerations. Furthermore, athletes performing unanticipated manoeuvres had a greater gastrocnemii contribution to posterior accelerations, indicating a higher mechanical ACL load. These findings highlight the importance of optimizing ACL rehabilitation, as muscle function may not be fully restored, potentially contributing to the recurrence of ACL injurie
Disrupting Niceness in Literacy Teacher Education: Non-linear Trajectories Toward Culturally Relevant Pedagogy
Get PDFMany teacher educators seek to implement culturally relevant pedagogy (CRP) in their courses. However, enactment is often mediated by our socialization into whiteness and niceness. This study investigates how our self-study community of practice (SSCoP) of eight White female literacy teacher educators at different institutions collaborated to narrow the gap between our aspirations for implementing CRP and enacted practice. Through analysis of collaborative journal entries, we interpret tensions between what niceness and whiteness demand of us and what enactment of CRP requires: (a) between centering equity in our courses and addressing equity on the margins, (b) between enactment of critical pedagogy and maintaining status as “nice” educators, and (c) between the expectation of expertise and the necessity of a learning stance. We argue that teacher educators might use SSCoP spaces to navigate the complex interplay between their identities and the sociopolitical context of teacher education to more fully enact CRP