3D Printed Embedded Force Sensors

Additive Manufacturing and 3D printing has opened the door to an endless amount of opportunities, including recent advances in conductive and resistive circuit printing. Taking advantage of these new technologies, we have designed a 3D printed insole with embedded plantar pressure sensor arrays. The customizable aspect of 3D printing allowed us to uniquely design a multitude of sensors. With the use of a dual extrusion printer we were able to produce a model that printed both the resistive circuit and complete insole simultaneously. These distinctive technologies have given us the capability to capture valuable pressure data from the sole of the foot. Analog signals sent from the pressure sensor arrays are received and processed through an attached multiplexer designed specifically for this application. The signal is then digitized and transmitted over the SPI transfer protocol to a processor and wirelessly communicated, via Bluetooth Low Energy, to a mobile android device to allow the user to easily record and interpret the array\u27s pressure data in real-time. The android device houses a pressure mapping view to show the gradient of force throughout the insole. With the capabilities of this insole we have provided an avenue for physicians and physical therapists to gather quantifiable insight into their patient\u27s progression throughout the rehabilitation process. With more intelligent and personalized data the applications of this technology are countless.https://scholarscompass.vcu.edu/capstone/1147/thumbnail.jp

Prospectus, April 4, 2019

PARKLAND STUDENTS GIVE BACK ON SPRING BREAK, Strengthening the Interaction Between Local and International Students: Opinion Piece, Mel Brooks\u27 Young Frankenstein Opening Night, Station Theater\u27s Marisol Will Rock You!, Student Government Candidates and Voting Schedule, Minder, Newton Selected as Parkland Athletes of Month, Parkland Golf: Evan MacLean Wins Purgatory Invite,https://spark.parkland.edu/prospectus_2019/1009/thumbnail.jp

Harbour seals consume more juvenile and adult salmon in estuaries than elsewhere in the Strait of Georgia

Recent studies of harbour seal diets (2012-2014) have been used to estimate the amounts of salmon consumed by seals in the Strait of Georgia. However, these diet data have primarily come from estuary habitats, and may not be representative of all seals. We analysed 1,317 scat samples collected at an estuary (Cowichan Bay) and 7 non-estuary sites from Apr–Nov 2016 and Apr–May 2017 to compare salmon consumption inside and outside of estuaries. Using high-throughput DNA techniques, we determined seals consumed a wide range of prey (n = 238 species)—with gadids (primarily hake) and forage fish (primarily herring) dominating diets in both habitats (typically \u3e75% of diet when combined). Salmonids were consumed throughout the year. Juvenile salmonids (based on life-histories and size of recovered bones) collectively made up 1.4% (CI = 0.8–2.1%) of the spring diet at non-estuaries and 2.5% (CI = 1.4–3.9%) in Cowichan Bay in 2016/17. Primary juvenile salmon consumed were chinook, and to a lesser extent coho and chum. The 1.1% difference between sites is considerable when translated into number of smolts consumed, and indicates smolt predation was 50% higher at our estuary site. Salmon consumption spiked in the fall (driven by returning adult chum salmon), and was much higher in Cowichan Bay (35%, CI = 29–40%) than at non-estuary sites (9.1%, CI = 7.3–11.0%). Furthermore, the bulk of salmon consumed at non-estuary locations was driven by one site (Belle Chain Islets) which appeared to be heavily influenced by Fraser River runs. Our findings highlight that estuaries may not be useful as proxies for non-estuary sites when assessing predation on species of conservation concern (including salmonids) and that models estimating harbour seal related salmon mortality should consider differences in consumption rates inside and outside of estuaries in the Salish Sea

Elemental Abundances of Kepler Objects of Interest in APOGEE. I. Two Distinct Orbital Period Regimes Inferred from Host Star Iron Abundances

The Apache Point Observatory Galactic Evolution Experiment (APOGEE) has observed $\sim$600 transiting exoplanets and exoplanet candidates from \textit{Kepler} (Kepler Objects of Interest, KOIs), most with $\geq$18 epochs. The combined multi-epoch spectra are of high signal-to-noise (typically $\geq$100) and yield precise stellar parameters and chemical abundances. We first confirm the ability of the APOGEE abundance pipeline, ASPCAP, to derive reliable [Fe/H] and effective temperatures for FGK dwarf stars -- the primary \textit{Kepler} host stellar type -- by comparing the ASPCAP-derived stellar parameters to those from independent high-resolution spectroscopic characterizations for 221 dwarf stars in the literature. With a sample of 282 close-in ($P<100$ days) KOIs observed in the APOGEE KOI goal program, we find a correlation between orbital period and host star [Fe/H] characterized by a critical period, $P_\mathrm{crit}$= $8.3^{+0.1}_{-4.1}$ days, below which small exoplanets orbit statistically more metal-enriched host stars. This effect may trace a metallicity dependence of the protoplanetary disk inner-radius at the time of planet formation or may be a result of rocky planet ingestion driven by inward planetary migration. We also consider that this may trace a metallicity dependence of the dust sublimation radius, but find no statistically significant correlation with host $T_\mathrm{eff}$ and orbital period to support such a claim.Comment: 18 Pages, Accepted to A

Kepler-730: A hot Jupiter system with a close-in, transiting, Earth-sized planet

Kepler-730 is a planetary system hosting a statistically validated hot Jupiter in a 6.49-day orbit and an additional transiting candidate in a 2.85-day orbit. We use spectroscopic radial velocities from the APOGEE-2N instrument, Robo-AO contrast curves, and Gaia distance estimates to statistically validate the planetary nature of the additional Earth-sized candidate. We perform astrophysical false positive probability calculations for the candidate using the available Kepler data and bolster the statistical validation by using radial velocity data to exclude a family of possible binary star solutions. Using a radius estimate for the primary star derived from stellar models, we compute radii of $1.100^{+0.047}_{-0.050}\ R_{Jup}$ and $0.140\pm0.012\ R_{Jup}$ ($1.57\pm0.13\ R_{\oplus}$) for Kepler-730b and Kepler-730c, respectively. Kepler-730 is only the second compact system hosting a hot Jupiter with an inner, transiting planet.Comment: 13 pages, 2 figures, 3 tables, published in ApJ

TOI-150: A transiting hot Jupiter in the TESS southern CVZ

We report the detection of a hot Jupiter ($M_{p}=1.75_{-0.17}^{+0.14}\ M_{J}$,$R_{p}=1.38\pm0.04\ R_{J}$) orbiting a middle-aged star ($\log g=4.152^{+0.030}_{-0.043}$) in the Transiting Exoplanet Survey Satellite (TESS) southern continuous viewing zone ($\beta=-79.59^{\circ}$). We confirm the planetary nature of the candidate TOI-150.01 using radial velocity observations from the APOGEE-2 South spectrograph and the Carnegie Planet Finder Spectrograph, ground-based photometric observations from the robotic Three-hundred MilliMeter Telescope at Las Campanas Observatory, and Gaia distance estimates. Large-scale spectroscopic surveys, such as APOGEE/APOGEE-2, now have sufficient radial velocity precision to directly confirm the signature of giant exoplanets, making such data sets valuable tools in the TESS era. Continual monitoring of TOI-150 by TESS can reveal additional planets and subsequent observations can provide insights into planetary system architectures involving a hot Jupiter around a star about halfway through its main-sequence life.Comment: 13 pages, 3 figures, 2 tables, accepted to ApJ

Characterization of low-mass companions to Kepler\textit{Kepler} objects of interest observed with APOGEE-N

We report the characterization of 28 low-mass ($0.02\mathrm{~M_\odot}\le\mathrm{~M_{2}}\le0.25\mathrm{~M_\odot}$) companions to $\textit{Kepler}$ objects of interest (KOIs), eight of which were previously designated confirmed planets. These objects were detected as transiting companions to Sun-like stars (G and F dwarfs) by the $\textit{Kepler}$ mission and are confirmed as single-lined spectroscopic binaries in the current work using the northern multiplexed Apache Point Observatory Galactic Evolution Experiment near-infrared spectrograph (APOGEE-N) as part of the third and fourth Sloan Digital Sky Surveys. We have observed hundreds of KOIs using APOGEE-N and collected a total of 43,175 spectra with a median of 19 visits and a median baseline of $\sim1.9$ years per target. We jointly model the $\textit{Kepler}$ photometry and APOGEE-N radial velocities to derive fundamental parameters for this subset of 28 transiting companions. The radii for most of these low-mass companions are over-inflated (by $\sim10\%$) when compared to theoretical models. Tidally locked M dwarfs on short period orbits show the largest amount of inflation, but inflation is also evident for companions that are well separated from the host star. We demonstrate that APOGEE-N data provides reliable radial velocities when compared to precise high-resolution spectrographs that enable detailed characterization of individual systems and the inference of orbital elements for faint ($H>12$) KOIs. The data from the entire APOGEE-KOI program is public and presents an opportunity to characterize an extensive subset of the binary population observed by $\textit{Kepler}$.Comment: 98 pages (include 56 for the figure sets), 10 tables, 7 figures, 2 figure sets, accepted for publication in ApJ

Kepler-503b: An Object at the Hydrogen Burning Mass Limit Orbiting a Subgiant Star

Using spectroscopic radial velocities with the APOGEE instrument and Gaia distance estimates, we demonstrate that Kepler-503b, currently considered a validated Kepler planet, is in fact a brown-dwarf/low-mass star in a nearly circular 7.2-day orbit around a subgiant star. Using a mass estimate for the primary star derived from stellar models, we derive a companion mass and radius of $0.075\pm0.003 \ M_{\odot}$ ($78.6\pm3.1 \ M_{Jup}$) and $0.099^{+0.006}_{-0.004}\ R_{\odot}$ ($0.96^{+0.06}_{-0.04}\ R_{Jup}$), respectively. Assuming the system is coeval, the evolutionary state of the primary indicates the age is $\sim6.7$ Gyr. Kepler-503b sits right at the hydrogen burning mass limit, straddling the boundary between brown dwarfs and very low-mass stars. More precise radial velocities and secondary eclipse spectroscopy with James Webb Space Telescope will provide improved measurements of the physical parameters and age of this important system to better constrain and understand the physics of these objects and their spectra. This system emphasizes the value of radial velocity observations to distinguish a genuine planet from astrophysical false positives, and is the first result from the SDSS-IV monitoring of Kepler planet candidates with the multi-object APOGEE instrument.Comment: Accepted for publication in ApJL, 12 pages, 3 figures, 2 table

THE DATA REDUCTION PIPELINE FOR THE APACHE POINT OBSERVATORY GALACTIC EVOLUTION EXPERIMENT

The Apache Point Observatory Galactic Evolution Experiment (APOGEE), part of the Sloan Digital Sky Survey III, explores the stellar populations of the Milky Way using the Sloan 2.5-m telescope linked to a high resolution (R ~ 22,500), near-infrared (1.51–1.70 µm) spectrograph with 300 optical fibers. For over 150,000 predominantly red giant branch stars that APOGEE targeted across the Galactic bulge, disks and halo, the collected high signal-to-noise ratio (>100 per half-resolution element) spectra provide accurate (~0.1 km s-1) RVs, stellar atmospheric parameters, and precise (lesssim0.1 dex) chemical abundances for about 15 chemical species. Here we describe the basic APOGEE data reduction software that reduces multiple 3D raw data cubes into calibrated, well-sampled, combined 1D spectra, as implemented for the SDSS-III/APOGEE data releases (DR10, DR11 and DR12). The processing of the near-IR spectral data of APOGEE presents some challenges for reduction, including automated sky subtraction and telluric correction over a 3°-diameter field and the combination of spectrally dithered spectra. We also discuss areas for future improvement