Can the Forward-Step-Down Test Be Used Reliably in the Clinical Setting to Assess Movement Changes Resulting from Maximal Exertion? A Pilot Study

Introduction: Visual assessment of lower extremity mechanics is used frequently in clinical practice, and objective scoring of the visual assessment is beneficial to improve objectivity of patient evaluation. In addition, lower extremity mechanics change with fatigue and these changes may increase the risk of lower extremity injury. The Forward-Step-Down Test (FSDT) is one such objective tool, but its ability to detect changes in movement quality in response to exertion are not known. Methods: This study utilized a repeated-measures design, where the participants were scored on the FSDT before performing the Bruce protocol for an exertion stimulus. The participants were re-scored on the FSDT at one, five, and ten minutes after completing the Bruce protocol. Results: Wilcoxon signed-rank tests showed a significant change in FSDT score between baseline and five minutes post-exertion (a\u3c .017). Friedman’s ANOVA was non-significant across all four assessments. In addition, despite testing healthy young adults, 50% of participants scored as “poor” movement quality on the initial test. This number increased to 75% at significant five-minute post-exertion mark. Discussion: Median scores on the FSDT were significantly different at five minutes post-exertion. However, this statistically significant change is of questionable clinical relevance because the median score changed by 0.5. This small change from 3.5 to 4.0 may not represent a change in overall movement quality from “moderate” to “poor.” Results do indicate that the participants in this study overall had poorer than expected movement quality throughout the testing. These results suggest larger data collection and analysis may be warranted for this population and the general population prior to partaking in exercise. Conclusion: The FSDT detects changes in lower extremity mechanics five minutes following a single exertion stimulus. Participants’ scores returned to baseline by ten minutes post-exertion. The FSDT may be a viable tool to assess changes in lower extremity movement quality following a single bout of exertion, and may help determine when participants have recovered back to baseline movement quality

Shock Synthesis of Organic Molecules by Meteoroids in the Atmosphere of Titan

Thermochemical modeling and shock-tube experiments show that shocks applied to N$_2$/CH$_4$ gas mixtures can synthesize organic molecules. Sufficiently large, hypersonic meteoroids entering the atmosphere of Saturn's moon Titan should therefore drive organic chemistry. To do so meteoroids must be sufficiently large compared to the atmospheric mean free path at a given altitude to generate shocks, and deposit enough energy per path length to produce temperatures high enough to excite and dissociate the relevant molecules. The Cassini spacecraft imaged multiple meteoroid impacts on Saturn's rings, allowing for the first time an empirical estimate to be made of the flux and size-frequency distributions of meteoroids in the millimeter-to-meter size range. We combine these results with an atmospheric entry model and thermochemical and experimental shock production efficiencies for N$_2$/CH$_4$ atmospheres and calculate the shock production rates for HCN, C$_2$H$_2$, and C$_2$H$_4$ as well as the resulting H$_2$ generation. We find that meteoroids may be producing these molecules at as much as $\sim$1% the production rate of photochemistry driven by UV photons, and may be depositing more energy than magnetospheric ions and 90-100 nm UV photons. Moreover, these meteoroids produce these organic molecules hundreds of kilometers lower in Titan's atmosphere than the relevant UV photons and magnetospheric ions penetrate, with peak production occurring between 200 and 500 km altitudes, i.e., at the observed haze layer. Meteoroid-driven shock generation of molecules may therefore be crucial to understanding Titan's atmospheric chemistry.Comment: 12 pages, 6 figure

Investigation of Academic Self-Concept of Undergraduates in STEM Courses

Academic self-concept is an important component of undergraduate student success. Academic self-concept refers to an individual's perception about their academic aptitude in a particular academic field. The purpose of this science education research study was to examine the effects of online and traditional (face-to-face) courses on academic self-concept. Undergraduate students enrolled in online and traditional science, technology, engineering, and mathematics (STEM) courses were administered the academic self-concept scale (ASCS). The ASCS measures students' perceptions of their capacity to attain academic success. Research findings indicate that online students were more likely to report a higher academic self-concept than traditional students enrolled in STEM courses. Future research studies will reveal the factors that underpin academic self-concept for students enrolled in STEM courses. Additional research on the mediators that influence positive academic self-concept are necessary to further inform online and traditional pedagogical strategies

PRN OPINION PAPER: Application of precision medicine across pharmacy specialty areas

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/149551/1/jac51107_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/149551/2/jac51107.pd

The Magellan-TESS Survey I: Survey Description and Mid-Survey Results

One of the most significant revelations from Kepler is that roughly one-third of Sun-like stars host planets which orbit their stars within 100 days and are between the size of Earth and Neptune. How do these super-Earth and sub-Neptune planets form, what are they made of, and do they represent a continuous population or naturally divide into separate groups? Measuring their masses and thus bulk densities can help address these questions of their origin and composition. To that end, we began the Magellan-TESS Survey (MTS), which uses Magellan II/PFS to obtain radial velocity (RV) masses of 30 transiting exoplanets discovered by TESS and develops an analysis framework that connects observed planet distributions to underlying populations. In the past, RV measurements of small planets have been challenging to obtain due to the faintness and low RV semi-amplitudes of most Kepler systems, and challenging to interpret due to the potential biases in the existing ensemble of small planet masses from non-algorithmic decisions for target selection and observation plans. The MTS attempts to minimize these biases by focusing on bright TESS targets and employing a quantitative selection function and multi-year observing strategy. In this paper, we (1) describe the motivation and survey strategy behind the MTS, (2) present our first catalog of planet mass and density constraints for 25 TESS Objects of Interest (TOIs; 20 in our population analysis sample, five that are members of the same systems), and (3) employ a hierarchical Bayesian model to produce preliminary constraints on the mass-radius (M-R) relation. We find qualitative agreement with prior mass-radius relations but some quantitative differences (abridged). The the results of this work can inform more detailed studies of individual systems and offer a framework that can be applied to future RV surveys with the goal of population inferences.Comment: 101 pages (39 of main text and references, the rest an appendix of figures and tables). Submitted to AAS Journal

The Multiplanet System TOI-421: A Warm Neptune and a Super Puffy Mini-Neptune Transiting a G9 V Star in a Visual Binary

We report the discovery of a warm Neptune and a hot sub-Neptune transiting TOI-421 (BD-14 1137, TIC 94986319), a bright (V = 9.9) G9 dwarf star in a visual binary system observed by the Transiting Exoplanet Survey Satellite (TESS) space mission in Sectors 5 and 6. We performed ground-based follow-up observations—comprised of Las Cumbres Observatory Global Telescope transit photometry, NIRC2 adaptive optics imaging, and FIbre-fed Echellé Spectrograph, CORALIE, High Accuracy Radial velocity Planet Searcher, High Resolution Échelle Spectrometer, and Planet Finder Spectrograph high-precision Doppler measurements—and confirmed the planetary nature of the 16 day transiting candidate announced by the TESS team. We discovered an additional radial velocity signal with a period of five days induced by the presence of a second planet in the system, which we also found to transit its host star. We found that the inner mini-Neptune, TOI-421 b, has an orbital period of P_b = 5.19672 ± 0.00049 days, a mass of M_b = 7.17 ± 0.66 M⊕, and a radius of R_b = 2.68^(+0.19)_(-0.18) R⊕, whereas the outer warm Neptune, TOI-421 c, has a period of Pc = 16.06819 ± 0.00035 days, a mass of M_c = 16.42^(+1.06)_(-1.04) M⊕, a radius of R_c = 5.09^(+0.16)_(-0.15) R⊕ and a density of ρ_c = 0.685^(+0.080)_(-0.072) g cm⁻³. With its characteristics, the outer planet (ρ_c = 0.685^(+0.080)_(-0.072) g cm⁻³) is placed in the intriguing class of the super-puffy mini-Neptunes. TOI-421 b and TOI-421 c are found to be well-suited for atmospheric characterization. Our atmospheric simulations predict significant Lyα transit absorption, due to strong hydrogen escape in both planets, as well as the presence of detectable CH4 in the atmosphere of TOI-421 c if equilibrium chemistry is assumed

Revisiting the HD 21749 planetary system with stellar activity modelling

HD 21749 is a bright (V = 8.1 mag) K dwarf at 16 pc known to host an inner terrestrial planet HD 21749c as well as an outer sub-Neptune HD 21749b, both delivered by Transiting Exoplanet Survey Satellite (TESS). Follow-up spectroscopic observations measured the mass of HD 21749b to be 22.7 ± 2.2 M with a density of 7.0^{+1.6}_{-1.3} g cm-3, making it one of the densest sub-Neptunes. However, the mass measurement was suspected to be influenced by stellar rotation. Here, we present new high-cadence PFS RV data to disentangle the stellar activity signal from the planetary signal. We find that HD 21749 has a similar rotational time-scale as the planet's orbital period, and the amplitude of the planetary orbital RV signal is estimated to be similar to that of the stellar activity signal. We perform Gaussian process regression on the photometry and RVs from HARPS and PFS to model the stellar activity signal. Our new models reveal that HD 21749b has a radius of 2.86 ± 0.20 R, an orbital period of 35.6133 ± 0.0005 d with a mass of Mb = 20.0 ± 2.7 M and a density of 4.8^{+2.0}_{-1.4} g cm-3 on an eccentric orbit with e = 0.16 ± 0.06, which is consistent with the most recent values published for this system. HD 21749c has an orbital period of 7.7902 ± 0.0006 d, a radius of 1.13 ± 0.10 R, and a 3σ mass upper limit of 3.5 M. Our Monte Carlo simulations confirm that without properly taking stellar activity signals into account, the mass measurement of HD 21749b is likely to arrive at a significantly underestimated error bar

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead