Voluntary Wheel Running Improves Recovery from Muscle Disuse in Mice

The reloading of atrophied muscles from weightlessness or disuse results in injury and prolonged recovery. Satellite cells, or muscle stem cells, have a key role in facilitating injury-induced muscle repair but have not been shown to be required in muscle remodeling following atrophy. However, it has been less clear if low-impact exercise, such as voluntary wheel running, could provide a sufficient stimulus to enhance muscle recovery from atrophy through satellite cell activation. This study aimed to determine if voluntary wheel running improved recovery from muscle disuse following hindlimb suspension unloading (HSU), and if the recovery was associated with exercise-induced satellite cell activity. Young adult male and female C57BL/6 background mice (n=6/group) were subjected to either 14 days of normal weight bearing, 14 days of HSU, 14 days of HSU + 14 days of re-ambulation, 14 days of voluntary wheel running, or 14 days of HSU + 14 days of voluntary wheel running. Mice were given 5-bromo-2\u27-deoxyuridine (BrdU) in their drinking water during the final 14 days of the experiment to measure satellite cell proliferation in gastrocnemius muscle fibers. HSU significantly reduced in vivo maximal force and decreased the rate of fatigue in the plantarflexor muscles. Voluntary wheel running during reloading after HSU significantly improved resistance to fatigue, which was associated with significant increases in both muscle fiber cross sectional area (CSA) and an increased percentage of oxidative type IIA muscle fibers in the gastrocnemius muscle as compared to the mice recovering without exercise. BrdU positive nuclei that had proliferated and were located inside the muscle sarcolemma were identified by immunohistochemical labeling and quantified in tissue cross sections. Following HSU, wheel running mice had a significantly greater percentage of BrdU positive nuclei that were inside gastrocnemius muscle fibers. Western blot analysis showed HSU mice with wheel running had a higher MyoD to Pax7 ratio as compared to mice that did not exercise after HSU. Mice in the wheel running group had significantly improved fatigue resistance, a significantly increased oxidative fiber phenotype, and significantly increased fiber CSA as compared to non-exercised animals after HSU. These results indicate that voluntary wheel running increased satellite cell activity during the recovery phase following HSU and this was associated with improved recovery from muscle disuse. While satellite cells did not exhibit increased activity in passive recovery (non-wheel running), manipulating their activation through low-impact exercise appeared to enhance morphological recovery and improve muscle function

Effective elements of conducting: A study of high school orchestra directors

The purpose of this study was to evaluate how effectively current high school orchestra directors demonstrate the elements of conducting. To do this, I first selected what elements of conducting would be evaluated and then defined what is effective for each. From this, I created a conductor evaluation form consisting of a 1-Not Effective to 5-Effective rating scale to score how effectively each element is demonstrated. The results would later address the primary research questions: What elements of conducting do high school orchestra directors demonstrate most effectively? What elements of conducting do high school orchestra directors demonstrate least effectively? Current high school orchestra directors from all parts of Virginia and portions of Maryland and Washington, D.C. were contacted to take part in this study. Twenty conductors from diverse regions of Virginia and Maryland agreed to participate. The participation of the conductors involved signing a consent form and then allowing me to digitally video record them conducting in their normal high school orchestra rehearsal setting. After all participants were recorded, I reviewed the video recordings to evaluate each element of conducting for each participant. Scores were then compiled to gain an understanding of which elements were demonstrated most and least effectively. The results indicate that high school orchestra directors demonstrate most effectively the technical elements of conducting: beat pattern, tempo, breath, and conducting area. The results, even more strongly, indicate that high school orchestra directors demonstrate least effectively the expressive elements of conducting: efficient joints, style in both non-dominant and dominant hands, and dynamics in both non-dominant and dominant hands. This qualitative study is limited and intended to inform those involved in the academic conducting community about the current state of conducting demonstrated by high school orchestra directors. It simply evaluates the physical elements of conducting and is not designed to provide a total conductor effectiveness rating nor evaluate the musical effectiveness, teacher effectiveness, or effectiveness of student understanding or learning

Short-term Response of Holcus lanatus L. (Common Velvetgrass) to Chemical and Manual Control at Yosemite National Park, USA

One of the highest priority invasive species at both Yosemite and Sequoia and Kings Canyon national parks is Holcus lanatus L. (common velvetgrass), a perennial bunchgrass that invades mid-elevation montane meadows. Despite velvetgrass being a high priority species, there is little information available on control techniques. The goal of this project was to evaluate the short-term response of a single application of common chemical and manual velvetgrass control techniques. The study was conducted at three montane sites in Yosemite National Park. Glyphosate spotspray treatments were applied at 0.5, 1.0, 1.5, and 2.0% concentrations, and compared with hand pulling to evaluate effects on cover of common velvetgrass, cover of other plant species, and community species richness. Posttreatment year 1 cover of common velvetgrass was 12.1% 6 1.6 in control plots, 6.3% 6 1.5 averaged over the four chemical treatments (all chemical treatments performed similarly), and 13.6% 6 1.7 for handpulled plots. This represents an approximately 50% reduction in common velvetgrass cover in chemically- treated plots recoded posttreatment year 1 and no statistically significant reduction in hand pulled plots compared with controls. However, there was no treatment effect in posttreatment year 2, and all herbicide application rates performed similarly. In addition, there were no significant treatment effects on nontarget species or species richness. These results suggest that for this level of infestation and habitat type, (1) one year of hand pulling is not an effective control method and (2) glyphosate provides some level of control in the short-term without impact to nontarget plant species, but the effect is temporary as a single year of glyphosate treatment is ineffective over a twoyear period

Polarization dOTF: on-sky focal plane wavefront sensing

The differential Optical Transfer Function (dOTF) is a focal plane wavefront sensing method that uses a diversity in the pupil plane to generate two different focal plane images. The difference of their Fourier transforms recovers the complex amplitude of the pupil down to the spatial scale of the diversity. We produce two simultaneous PSF images with diversity using a polarizing filter at the edge of the telescope pupil, and a polarization camera to simultaneously record the two images. Here we present the first on-sky demonstration of polarization dOTF at the 1.0m South African Astronomical Observatory telescope in Sutherland, and our attempt to validate it with simultaneous Shack-Hartmann wavefront sensor images.Comment: 11 pages, 9 figures, Proc. SPIE Vol. 991

Topographic determinants of foot and mouth disease transmission in the UK 2001 epidemic

Background A key challenge for modelling infectious disease dynamics is to understand the spatial spread of infection in real landscapes. This ideally requires a parallel record of spatial epidemic spread and a detailed map of susceptible host density along with relevant transport links and geographical features. Results Here we analyse the most detailed such data to date arising from the UK 2001 foot and mouth epidemic. We show that Euclidean distance between infectious and susceptible premises is a better predictor of transmission risk than shortest and quickest routes via road, except where major geographical features intervene. Conclusion Thus, a simple spatial transmission kernel based on Euclidean distance suffices in most regions, probably reflecting the multiplicity of transmission routes during the epidemic

Reduction of blade-vortex interaction noise using higher harmonic pitch control

An acoustics test using an aeroelastically scaled rotor was conducted to examine the effectiveness of higher harmonic blade pitch control for the reduction of impulsive blade-vortex interaction (BVI) noise. A four-bladed, 110 in. diameter, articulated rotor model was tested in a heavy gas (Freon-12) medium in Langley's Transonic Dynamics Tunnel. Noise and vibration measurements were made for a range of matched flight conditions, where prescribed (open-loop) higher harmonic pitch was superimposed on the normal (baseline) collective and cyclic trim pitch. For the inflow-microphone noise measurements, advantage was taken of the reverberance in the hard walled tunnel by using a sound power determination approach. Initial findings from on-line data processing for three of the test microphones are reported for a 4/rev (4P) collective pitch control for a range of input amplitudes and phases. By comparing these results to corresponding baseline (no control) conditions, significant noise reductions (4 to 5 dB) were found for low-speed descent conditions, where helicopter BVI noise is most intense. For other rotor flight conditions, the overall noise was found to increase. All cases show increased vibration levels

Reducing “Treble” with Performance Focused Music Programs in Medical School: A Student Driven Needs Assessment to Clarify Participation Barriers Amongst Undergraduate Medical Students

Introduction: The beneficial impact of performing arts involvement within undergraduate medical education, such as music, has been studied, but support for the arts varies significantly by institution. Research has suggested that medical student involvement in the arts can help develop their identities as physicians and may reduce stress and burnout, an increasingly difficult problem within the medical student community. Methods: We used a mixed-method cross-sectional study design, using a questionnaire and semi-structured interview designed amongst a team of music professionals and healthcare providers with music backgrounds. Out of 511 enrolled medical students, 93 students participated in the study for a response rate of 18.2%. Questions were piloted among eight medical students, with modifications made in response to feedback. Participants were recruited to participate in an online survey via social media. Results: Within our sample, the most popular background instrument was piano (58.5%) and voice (50.0%). Of those who responded, most preferred to perform alone (85.7%) or in small groups (51.4%). 78.8% of respondents agreed that music was essential to their wellbeing. Only 62.5% of the respondents with musical backgrounds still play music or sing. Of those who no longer play music, 90.5% of respondents reported time constraint as the limiting factor, followed by lack of access to instruments (42.9%). Conclusion: This study suggests there are diverse music backgrounds and interests amongst the medical student population. Although most participants believed music was a form of stress relief, undergraduate medical training demands impose time restrictions on student engagement. Investments in music programs that enable adequate involvement and meet student demand have the potential to improve medical student engagement with the arts, alleviate stress, and may even lead to stronger/more empathetic physicians. Periodic needs assessments may be a powerful tool to better align programming to address student desires and reduce barriers

Ice Nucleation in Sulfuric Acid and Ammonium Sulfate Particles

Cirrus clouds are composed of ice particles and are expected to form in the upper troposphere when highly dilute sulfate aerosols cool and become supersaturated with respect to ice. In the laboratory we have used Fourier transform infrared spectroscopy to monitor ice nucleation from sulfate particles for relevant compositions of sulfuric acid/water and ammonium sulfate/water aerosols. Measured freezing temperatures are presented as a function of aerosol composition, and results are compared to existing aerosol data. We find that sulfuric acid solution aerosol exhibits greater supercooling than ammonium sulfate solution aerosol of similar weight percent. Ice saturation ratios based on these measurements are also reported. We find that ammonium sulfate solution aerosol exhibits a relatively constant ice saturation of S∼1.48 for ice nucleation from 232 to 222 K, while sulfuric acid solution aerosol shows an increase in ice saturation from S∼1.53 to S∼1.6 as temperature decreases from 220 K to 200 K. These high-saturation ratios imply selective nucleation of ice from sulfate aerosols