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1. Pulmonary artery stenting in cancer patients: A single-center experience

Author

Jay F. Gupta, Ronak Patel, Neal Patel, David Wynne, and Mohammad Ghasemi-Rad

Subjects
Pulmonary artery stenosis, Malignancy, Stent, Angiogram, Medical physics. Medical radiology. Nuclear medicine, R895-920
Abstract

Endovascular stenting of the pulmonary artery treats arterial stenosis from pulmonary hypertension, congenital heart defects, or post-transplant stricture. Patients with malignant extrinsic pulmonary arterial compression, secondary to large mediastinal or pulmonary masses, often present with dyspnea, hypoxemia, and right ventricular failure. Conventional therapies like surgery, chemotherapy, and radiation are often slow and fail to promptly resolve acute symptoms.Balloon angioplasty and stenting have been explored as a rapid treatment to alleviate symptoms of external pulmonary artery compression. Despite its potential, the adoption of this procedure is limited due to risks like stent misplacement, migration, cardiac arrhythmias, and arterial rupture.This paper presents 3 cases of pulmonary angiography and stenting performed for malignant extrinsic pulmonary artery compression. These cases aim to demonstrate the feasibility of pulmonary artery stenting, encouraging its consideration as a palliative option for symptomatic patients with this condition.

Published
2024
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2. TOI-4201: An Early M Dwarf Hosting a Massive Transiting Jupiter Stretching Theories of Core Accretion

Author

Megan Delamer, Shubham Kanodia, Caleb I. Cañas, Simon Müller, Ravit Helled, Andrea S. J. Lin, Jessica E. Libby-Roberts, Arvind F. Gupta, Suvrath Mahadevan, Johanna Teske, R. Paul Butler, Samuel W. Yee, Jeffrey D. Crane, Stephen Shectman, David Osip, Yuri Beletsky, Andrew Monson, Leslie Hebb, Luke C. Powers, John P. Wisniewski, Jaime A. Alvarado-Montes, Chad F. Bender, Jiayin Dong, Te Han, Joe P. Ninan, Paul Robertson, Arpita Roy, Christian Schwab, Guđmundur Stefánsson, and Jason T. Wright

Subjects
Exoplanet detection methods, Exoplanet astronomy, Exoplanet formation, Exoplanets, Radial velocity, Transit photometry, Astrophysics, QB460-466
Abstract

We confirm TOI-4201 b as a transiting Jovian-mass planet orbiting an early M dwarf discovered by the Transiting Exoplanet Survey Satellite. Using ground-based photometry and precise radial velocities from NEID and the Planet Finder Spectrograph, we measure a planet mass of ${2.59}_{-0.06}^{+0.07}$ M _J , making this one of the most massive planets transiting an M dwarf. The planet is ∼0.4% of the mass of its 0.63 M _⊙ host and may have a heavy-element mass comparable to the total dust mass contained in a typical class II disk. TOI-4201 b stretches our understanding of core accretion during the protoplanetary phase and the disk mass budget, necessitating giant planet formation to take place either much earlier in the disk lifetime or perhaps through alternative mechanisms like gravitational instability.

Published
2024
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4. Gaspery: Optimized Scheduling of Radial Velocity Follow-up Observations for Active Host Stars

Author

Christopher Lam, Megan Bedell, Lily L. Zhao, Arvind F. Gupta, and Sarah A. Ballard

Subjects
Exoplanets, Radial velocity, Stellar activity, Astronomy, QB1-991
Abstract

Radial velocity (RV) follow-up is a critical complement of transiting exoplanet surveys like the Transiting Exoplanet Survey Satellite, both for validating discoveries of exoplanets and measuring their masses. Stellar activity introduces challenges to interpreting these measurements because the noise from the host star, which is often correlated in time, can result in high RV uncertainty. A robust understanding of stellar activity and how its timescales interact with the observing cadence can optimize limited RV resources. For this reason, in the era of oversubscribed, high-precision RV measurements, folding stellar activity timescales into the scheduling of observation campaigns is ideal. We present gaspery , an open-source code implementation to enable the optimization of RV observing strategies. Gaspery employs a generalized formulation of the Fisher information for RV time series, which also incorporates information about stellar correlated noise. We show that the information contained in an observing strategy can be significantly affected by beat frequencies between the orbital period of the planet, the stellar rotation period, and the observation epochs. We investigate how the follow-up observing strategy will affect the resulting RV uncertainty, as a function of stellar properties such as the spot decay timescale and rotation period. We then describe two example use cases for gaspery : (1) calculating the minimum number of observations to reach an uncertainty tolerance in a correlated noise regime and (2) finding an optimal strategy given a fixed observing budget. Finally, we outline a prescription for selecting an observing strategy that is generalizable to different targets.

Published
2024
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5. TOI-2015 b: A Warm Neptune with Transit Timing Variations Orbiting an Active Mid-type M Dwarf

Author

Sinclaire E. Jones, Guđmundur Stefánsson, Kento Masuda, Jessica E. Libby-Roberts, Cristilyn N. Gardner, Rae Holcomb, Corey Beard, Paul Robertson, Caleb I. Cañas, Suvrath Mahadevan, Shubham Kanodia, Andrea S. J. Lin, Henry A. Kobulnicky, Brock A. Parker, Chad F. Bender, William D. Cochran, Scott A. Diddams, Rachel B. Fernandes, Arvind F. Gupta, Samuel Halverson, Suzanne L. Hawley, Fred R. Hearty, Leslie Hebb, Adam Kowalski, Jack Lubin, Andrew Monson, Joe P. Ninan, Lawrence Ramsey, Arpita Roy, Christian Schwab, Ryan C. Terrien, and John Wisniewski

Subjects
Exoplanets, M dwarf stars, Transits, Radial velocity, Transit timing variation method, Astronomy, QB1-991
Abstract

We report the discovery of a close-in ( P _orb = 3.349 days) warm Neptune with clear transit timing variations (TTVs) orbiting the nearby ( d = 47.3 pc) active M4 star, TOI-2015. We characterize the planet's properties using Transiting Exoplanet Survey Satellite (TESS) photometry, precise near-infrared radial velocities (RVs) with the Habitable-zone Planet Finder Spectrograph, ground-based photometry, and high-contrast imaging. A joint photometry and RV fit yields a radius ${R}_{p}={3.37}_{-0.20}^{+0.15}\ {R}_{\oplus }$ , mass ${m}_{p}={16.4}_{-4.1}^{+4.1}\ {M}_{\oplus }$ , and density ${\rho }_{p}\,={2.32}_{-0.37}^{+0.38}\ {\rm{g}}\ {\mathrm{cm}}^{-3}$ for TOI-2015 b, suggesting a likely volatile-rich planet. The young, active host star has a rotation period of P _rot = 8.7 ± 0.9 days and associated rotation-based age estimate of 1.1 ± 0.1 Gyr. Though no other transiting planets are seen in the TESS data, the system shows clear TTVs of super-period ${P}_{\sup }\approx 430\ \mathrm{days}$ and amplitude ∼100 minutes. After considering multiple likely period-ratio models, we show an outer planet candidate near a 2:1 resonance can explain the observed TTVs while offering a dynamically stable solution. However, other possible two-planet solutions—including 3:2 and 4:3 resonances—cannot be conclusively excluded without further observations. Assuming a 2:1 resonance in the joint TTV-RV modeling suggests a mass of ${m}_{b}={13.3}_{-4.5}^{+4.7}\ {M}_{\oplus }$ for TOI-2015 b and ${m}_{c}={6.8}_{-2.3}^{+3.5}\ {M}_{\oplus }$ for the outer candidate. Additional transit and RV observations will be beneficial to explicitly identify the resonance and further characterize the properties of the system.

Published
2024
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6. Fishing for Planets: A Comparative Analysis of EPRV Survey Performance in the Presence of Correlated Noise

Author

Arvind F. Gupta and Megan Bedell

Subjects
Exoplanet detection methods, Radial velocity, Surveys, Fisher's Information, Stellar activity, Astronomy, QB1-991
Abstract

With dedicated exoplanet surveys underway for multiple extreme-precision radial velocity (EPRV) instruments, the near-future prospects of RV exoplanet science are promising. These surveys’ generous time allocations are expected to facilitate the discovery of Earth analogs around bright, nearby Sun-like stars. But survey success will depend critically on the choice of observing strategy, which will determine the survey’s ability to mitigate known sources of noise and extract low-amplitude exoplanet signals. Here we present an analysis of the Fisher information content of simulated EPRV surveys, accounting for the most recent advances in our understanding of stellar variability on both short and long timescales (i.e., oscillations and granulation within individual nights, and activity-induced variations across multiple nights). In this analysis, we capture the correlated nature of stellar variability by parameterizing these signals with Gaussian process kernels. We describe the underlying simulation framework and the physical interpretation of the Fisher information content, and we evaluate the efficacy of EPRV survey strategies that have been presented in the literature. We explore and compare strategies for scheduling observations over various timescales, and we make recommendations to optimize survey performance for the detection of Earth-like exoplanets.

Published
2024
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7. Confirming the Warm and Dense Sub-Saturn TIC 139270665 b with the Automated Planet Finder and Unistellar Citizen Science Network

Author

Daniel O’Conner Peluso, Paul A. Dalba, Duncan Wright, Thomas M. Esposito, Lauren A. Sgro, Ian C. Weaver, Franck Marchis, Diana Dragomir, Steven Villanueva Jr., Benjamin Fulton, Howard Isaacson, Arvind F. Gupta, Thomas Lee Jacobs, Daryll M. LaCourse, Robert Gagliano, Martti H. Kristiansen, Mark Omohundro, Hans M. Schwengeler, Ivan A. Terentev, Andrew Vanderburg, Ananya Balakrishnan, Divya Bhamidipati, Marco Hovland, Serina Jain, Nathan Jay, Hanna Johnson, Aditya Kapur, Jonah Morgan, Josephine Oesterer, Richard Purev, Dean Ramos, Christopher Seo, Vibha Sriramkumar, Naina Srivastava, Astha Verma, Olivia Woo, Steven Adkinson, Keiichi Fukui, Patrice Girard, Tateki Goto, Bruno Guillet, Des Janke, Andre Katterfeld, Rachel Knight, David Koster, Ryuichi Kukita, Eric Lawson, Liouba Leroux, Niniane Leroux, Chelsey Logan, Margaret A. Loose, Nicola Meneghelli, Eric Oulevey, Bruce Parker, Stephen Price, Michael Primm, Justus Randolph, Robert Savonnet, Masao Shimizu, Petri Tikkanen, Stefan Will, Neil Yoblonsky, and Wai-Chun Yue

Subjects
Exoplanet astronomy, Amateur astronomy, Radial velocity, Transit photometry, Extrasolar gaseous giant planets, Extrasolar gaseous planets, Astronomy, QB1-991
Abstract

We report the discovery and confirmation of the Transiting Exoplanet Survey Satellite (TESS) single-transit, warm and dense sub-Saturn, TIC 139270665 b. This planet is unusually dense for its size: with a bulk density of 2.13 g cm ^−3 (0.645 R _J , 0.463 M _J ), it is the densest warm sub-Saturn of the TESS family. It orbits a metal-rich G2 star. We also found evidence of a second planet, TIC 139270665 c, with a longer period of ${1010}_{-220}^{+780}$ days and minimum mass ${M}_{P}\sin i$ of ${4.89}_{-0.37}^{+0.66}$ M _J . First clues of TIC 139270665 b’s existence were found by citizen scientists inspecting TESS photometric data from sector 47 in 2022 January. Radial velocity measurements from the Automated Planet Finder combined with TESS photometry and spectral energy distributions via EXOFASTv2 system modeling suggested a ${23.624}_{-0.031}^{+0.030}$ day orbital period for TIC 139270665 b and also showed evidence for the second planet. Based on this estimated period, we mobilized the Unistellar citizen science network for photometric follow-up, capitalizing on their global distribution to capture a second transit of TIC 139270665 b. This citizen science effort also served as a test bed for an education initiative that integrates young students into modern astrophysics data collection. The Unistellar photometry did not definitively detect a second transit, but did enable us to further constrain the planet’s period. As a transiting, warm, and dense sub-Saturn, TIC 139270665 b represents an interesting laboratory for further study to enhance our models of planetary formation and evolution.

Published
2024
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8. A High-Eccentricity Warm Jupiter Orbiting TOI-4127

Author

Arvind F. Gupta, Jonathan M. Jackson, Guillaume Hébrard, Andrea S. J. Lin, Keivan G. Stassun, Jiayin Dong, Steven Villanueva Jr, Diana Dragomir, Suvrath Mahadevan, Jason T. Wright, Jose M. Almenara, Cullen H. Blake, Isabelle Boisse, Pía Cortés-Zuleta, Paul A. Dalba, Rodrigo F. Díaz, Eric B. Ford, Thierry Forveille, Robert Gagliano, Samuel Halverson, Neda Heidari, Shubham Kanodia, Flavien Kiefer, David W. Latham, Michael W. McElwain, Ismael Mireles, Claire Moutou, Joshua Pepper, George R. Ricker, Paul Robertson, Arpita Roy, Martin Schlecker, Christian Schwab, S. Seager, Avi Shporer, Guđmundur Stefánsson, Ryan C. Terrien, Eric B. Ting, Joshua N. Winn, and Allison Ann Youngblood

Subjects
Astronomy, Astrophysics
Abstract

We report the discovery of TOI-4127 b, which is a transiting, Jupiter-sized exoplanet on a long period (P=56.39879 +0.00010-0.00010days) and a high-eccentricity orbit around a late F-type dwarf star. This warm Jupiter was first detected and identified as a promising candidate from a search for single-transit signals in TESS Sector 20 data and was later characterized as a planet following two subsequent transits (TESS Sectors 26 and 53) and follow-up ground-based RV observations with the NEID and SOPHIE spectrographs. We jointly fit the transit and RV data to constrain the physical (Rp=1.096+0.039-0.032RJ, Mp=2.30+0.11-0.11MJ) and orbital parameters of the exoplanet. Given its high orbital eccentricity (𝓮=0.7471+0.0078-0.0086), TOI-4127 b is a compelling candidate for studies of warm Jupiter populations and of hot Jupiter formation pathways. We show that the present periastron separation of TOI-4127 b is too large for high-eccentricity tidal migration to circularize its orbit, and that TOI-4127 b is unlikely to be a hot Jupiter progenitor unless it is undergoing angular momentum exchange with an undetected outer companion. Although we find no evidence for an external companion, the available observational data are insufficient to rule out the presence of a perturber that can excite eccentricity oscillations and facilitate tidal migration.

Published
2023
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9. TOI-1670 c, a 40 day Orbital Period Warm Jupiter in a Compact System, Is Well Aligned

Author

Jack Lubin, Xian-Yu Wang, Malena Rice, Jiayin Dong, Songhu Wang, Brandon T. Radzom, Paul Robertson, Gudmundur Stefansson, Jaime A. Alvarado-Montes, Corey Beard, Chad F. Bender, Arvind F. Gupta, Samuel Halverson, Shubham Kanodia, Dan Li, Andrea S. J. Lin, Sarah E. Logsdon, Emily Lubar, Suvrath Mahadevan, Joe P. Ninan, Jayadev Rajagopal, Arpita Roy, Christian Schwab, and Jason T. Wright

Subjects
Exoplanet dynamics, Astrophysics, QB460-466
Abstract

We report the measurement of the sky-projected obliquity angle λ of the warm Jovian exoplanet TOI-1670 c via the Rossiter–McLaughlin effect. We observed the transit window during UT 2023 April 20 for 7 continuous hours with NEID on the 3.5 m WIYN Telescope at Kitt Peak National Observatory. TOI-1670 hosts a sub-Neptune ( P ∼ 11 days; planet b) interior to the warm Jovian ( P ∼ 40 days; planet c), which presents an opportunity to investigate the dynamics of a warm Jupiter with an inner companion. Additionally, TOI-1670 c is now among the longest-period planets to date to have its sky-projected obliquity angle measured. We find planet c is well aligned to the host star, with λ = − 0.°3 ± 2.°2. TOI-1670 c joins a growing census of aligned warm Jupiters around single stars and aligned planets in multiplanet systems.

Published
2023
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10. NEID Reveals That the Young Warm Neptune TOI-2076 b Has a Low Obliquity

Author

Robert C. Frazier, Gudmundur Stefánsson, Suvrath Mahadevan, Samuel W. Yee, Caleb I. Cañas, Joshua N. Winn, Jacob Luhn, Fei Dai, Lauren Doyle, Heather Cegla, Shubham Kanodia, Paul Robertson, John Wisniewski, Chad F. Bender, Jiayin Dong, Arvind F. Gupta, Samuel Halverson, Suzanne Hawley, Leslie Hebb, Rae Holcomb, Adam Kowalski, Jessica Libby-Roberts, Andrea S. J. Lin, Michael W. McElwain, Joe P. Ninan, Cristobal Petrovich, Arpita Roy, Christian Schwab, Ryan C. Terrien, and Jason T. Wright

Subjects
Exoplanet dynamics, Exoplanet astronomy, Radial velocity, Transit photometry, Exoplanets, Mini Neptunes, Astrophysics, QB460-466
Abstract

TOI-2076 b is a sub-Neptune-sized planet ( R = 2.39 ± 0.10 R _⊕ ) that transits a young (204 ± 50 MYr) bright ( V = 9.2) K-dwarf hosting a system of three transiting planets. Using spectroscopic observations obtained with the NEID spectrograph on the WIYN 3.5 m Telescope, we model the Rossiter–McLaughlin effect of TOI-2076 b, and derive a sky-projected obliquity of $\lambda =-{3}_{-15}^{+16^\circ }$ . Using the size of the star ( R = 0.775 ± 0.015 R _⊙ ), and the stellar rotation period ( P _rot = 7.27 ± 0.23 days), we estimate an obliquity of $\psi ={18}_{-9}^{+10^\circ }$ ( ψ < 34° at 95% confidence), demonstrating that TOI-2076 b is in a well-aligned orbit. Simultaneous diffuser-assisted photometry from the 3.5 m telescope at Apache Point Observatory rules out flares during the transit. TOI-2076 b joins a small but growing sample of young planets in compact multi-planet systems with well-aligned orbits, and is the fourth planet with an age ≲300 Myr in a multi-transiting system with an obliquity measurement. The low obliquity of TOI-2076 b and the presence of transit timing variations in the system suggest the TOI-2076 system likely formed via convergent disk migration in an initially well-aligned disk.

Published
2023
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11. Detection of p-mode Oscillations in HD 35833 with NEID and TESS

Author

Arvind F Gupta, Jacob Luhn, Jason T Wright, Suvrath Mahadevan, Eric B Ford, Gudmundur Stefansson, Chad F Bender, Cullen H Blake, Samuel Halverson, Fred Hearty, Shubham Kanodia, Sarah E Logsdon, Michael W McElwain, Joe P Ninan, Paul Roberston, Arpita Roy, Christian Schwab, and Ryan C Terrien

Subjects
Astronomy
Abstract

We report the results of observations of p-mode oscillations in the G0 subgiant star HD 35833 in both radial velocities and photometry with NEID and TESS, respectively. We achieve separate, robust detections of the oscillation signal with both instruments (radial velocity amplitude ARV = 1.11 ± 0.09 m s−1, photometric amplitude Aphot = 6.42 ± 0.60 ppm, frequency of maximum power nmax = 595.71  17.28 μHz, and mode spacing Δν = 36.65 ± 0.96 μHz) as well as a nondetection in a TESS sector concurrent with the NEID observations. These data shed light on our ability to mitigate the correlated noise impact of oscillations with radial velocities alone and on the robustness of commonly used asteroseismic scaling relations. The NEID data are used to validate models for the attenuation of oscillation signals for exposure times t max < n-1 , and we compare our results to predictions from theoretical scaling relations and find that the observed amplitudes are weaker than expected by >4σ, hinting at gaps in the underlying physical models.

Published
2022
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12. GJ 3929: High-precision Photometric and Doppler Characterization of an Exo-Venus and Its Hot, Mini-Neptune-mass Companion

Author

Corey Beard, Paul Robertson, Shubham Kanodia, Jack Lubin, Caleb I Cañas, Arvind F Gupta, Rae Holcomb, Sinclaire Jones, Jessica E Libby-Roberts, Andrea S J Lin, Suvrath Mahadevan, Guđmundur Stefánsson, Chad F Bender, Cullen H Blake, William D Cochran, Michael Endl, Mark Everett, Eric B Ford, Connor Fredrick, Samuel Halverson, Leslie Hebb, Dan Li, Sarah E Logsdon, Jacob Luhn, Michael W McElwain, Andrew J Metcalf, Joe P Ninan, Jayadev Rajagopal, Arpita Roy, Maria Schutte, Christian Schwab, Ryan C Terrien, John Wisniewski, and Jason T Wright

Subjects
Astronomy
Abstract

We detail the follow-up and characterization of a transiting exo-Venus identified by TESS, GJ 3929b (TOI-2013b), and its nontransiting companion planet, GJ 3929c (TOI-2013c). GJ 3929b is an Earth-sized exoplanet in its star’s Venus zone (Pb = 2.616272 ± 0.000005 days; Sb = 17.3+0.8-0.7 S⊕) orbiting a nearby M dwarf. GJ 3929c is most likely a nontransiting sub-Neptune. Using the new, ultraprecise NEID spectrometer on the WIYN 3.5 m Telescope at Kitt Peak National Observatory, we are able to modify the mass constraints of planet b reported in previous works and consequently improve the significance of the mass measurement to almost 4σ confidence (Mb = 1.75 ± 0.45 M⊕). We further adjust the orbital period of planet c from its alias at 14.30 ± 0.03 days to the likely true period of 15.04 ± 0.03 days, and we adjust its minimum mass to m sin i = 5.71 ± 0.92 M⊕. Using the diffuser-assisted ARCTIC imager on the ARC 3.5 m telescope at Apache Point Observatory, in addition to publicly available TESS and LCOGT photometry, we are able to constrain the radius of planet b to Rp = 1.09 ± 0.04 R⊕. GJ 3929b is a top candidate for transmission spectroscopy in its size regime (TSM = 14 ± 4), and future atmospheric studies of GJ 3929b stand to shed light on the nature of small planets orbiting M dwarfs.

Published
2022
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13. The NEID Port Adapter on-Sky Performance

Author

Sarah E. Logsdon, Marsha J. Wolf, Dan Li, Jayadev Rajagopal, Mark Everett, Qian Gong, Eli Golub, Jesus Higuera, Emily Hunting, Kurt P. Jaehnig, Ming Liang, Wilson Liu, William R. McBride, Michael W. McElwain, Jeffrey W. Percival, Susan Ridgway, Heidi Schweiker, Michael P. Smith, Erik Timmermann, Fernando Santoro, Christian Schwab, Chad F. Bender, Cullen H. Blake, Arvind F. Gupta, Samuel Halverson, Fred Hearty, Shubham Kanodia, Suvrath Mahadevan, Andrew J. Monson, Joe Ninan, Lawrence Ramsey, Paul Robertson, Arpita Roy, Ryan C. Terrien, and Jason T. Wright

Subjects
Astronomy, Instrumentation and Photography
Abstract

Here we detail the on-sky performance of the NEID Port Adapter one year into full science operation at the WIYN 3.5m Telescope at Kitt Peak National Observatory. NEID is an optical (380-930 nm), fiber-fed, precision Doppler radial velocity system developed as part of the NASA-NSF Exoplanet Observational Research (NN-EXPLORE) partnership. The NEID Port Adapter mounts directly to a bent-Cassegrain port on the WIYN Telescope and is responsible for precisely and stably placing target light on the science fibers. Precision acquisition and guiding is a critical component of such extreme precision spectrographs. In this work, we describe key on-sky performance results compared to initial design requirements and error budgets. While the current Port Adapter performance is more than sufficient for the NEID system to achieve and indeed exceed its formal instrumental radial velocity precision requirements, we continue to characterize and further optimize its performance and efficiency. This enables us to obtain better NEID datasets and in some cases, improve the performance of key terms in the error budget needed for future extreme precision spectrographs with the goal of observing ExoEarths, requiring ∼ 10 cm/s radial velocity measurements.

Published
2022
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14. Real-Time Exposure Control and Instrument Operation With the NEID Spectrograph GUI

Author

Arvind F Gupta, Chad F Bender, Joe P Ninan, Sarah E Logsdon, Shubham Kanodia, Eli Golub, Jesus Higuera, Jessica Klusmeyer, Samuel Halverson, Suvrath Mahadevan, Michael W McElwain, Christian Schwab, Gudmundur Stefansson, Paul Robertson, Arpita Roy, Ryan Terrien, and Jason Wright

Subjects
Instrumentation and Photography
Abstract

The NEID spectrograph on the WIYN 3.5-m telescope at Kitt Peak has completed its first full year of science operations and is reliably delivering sub-m/s precision radial velocity measurements. The NEID instrument control system uses the TIMS package (Bender et al. 2016), which is a client-server software system built around the twisted python software stack. During science observations, interaction with the NEID spectrograph is handled through a pair of graphical user interfaces (GUIs), written in PyQT, which wrap the underlying instrument control software and provide straightforward and reliable access to the instrument. Here, we detail the design of these interfaces and present an overview of their use for NEID operations. Observers can use the NEID GUIs to set the exposure time, signal-to-noise ratio (SNR) threshold, and other relevant parameters for observations, configure the calibration bench and observing mode, track or edit observation metadata, and monitor the current state of the instrument. These GUIs facilitate automatic spectrograph configuration and target ingestion from the nightly observing queue, which improves operational efficiency and consistency across epochs. By interfacing with the NEID exposure meter, the GUIs also allow observers to monitor the progress of individual exposures and trigger the shutter on user-defined SNR thresholds. In addition, inset plots of the instantaneous and cumulative exposure meter counts as each observation progresses allow for rapid diagnosis of changing observing conditions as well as guiding failure and other emergent issues.

Published
2022
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15. TOI-3757 b: A Low-density Gas Giant Orbiting a Solar-metallicity M Dwarf

Author

Shubham Kanodia, Jessica Libby-Roberts, Caleb I. Cañas, Joe P. Ninan, Suvrath Mahadevan, Gudmundur Stefansson, Andrea S. J. Lin, Sinclaire Jones, Andrew Monson, Brock A. Parker, Henry A. Kobulnicky, Tera N. Swaby, Luke Powers, Corey Beard, Chad F. Bender, Cullen H. Blake, William D. Cochran, Jiayin Dong, Scott A. Diddams, Connor Fredrick, Arvind F. Gupta, Samuel Halverson, Fred Hearty, Sarah E. Logsdon, Andrew J. Metcalf, Michael W. McElwain, Caroline V. Morley, Jayadev Rajagopal, Lawrence W. Ramsey, Paul Robertson, Arpita Roy, Christian Schwab, Ryan C. Terrien, John P. Wisniewski, and Jason T. Wright

Subjects
Astronomy, Astrophysics
Abstract

We present the discovery of a new Jovian-sized planet, TOI-3757 b, the lowest-density transiting planet known to orbit an M dwarf (M0V). This planet was discovered around a solar-metallicity M dwarf, using Transiting Exoplanet Survey Satellite photometry and confirmed with precise radial velocities from the Habitable-zone Planet Finder (HPF) and NEID. With a planetary radius of 12.0 (+0.4 -0.5) R⊕ and mass of 85.3 (+8.8 -8.7)M⊕, not only does this object add to the small sample of gas giants (∼10) around M dwarfs, but also its low density (ρ=0.27 +0.05-0.04g) provides an opportunity to test theories of planet formation. We present two hypotheses to explain its low density; first, we posit that the low metallicity of its stellar host (∼0.3 dex lower than the median metallicity of M dwarfs hosting gas giants) could have played a role in the delayed formation of a solid core massive enough to initiate runaway accretion. Second, using the eccentricity estimate of 0.14 ± 0.06, we determine it is also plausible for tidal heating to at least partially be responsible for inflating the radius of TOI-3757b b. The low density and large scale height of TOI-3757 b makes it an excellent target for transmission spectroscopy studies of atmospheric escape and composition (transmission spectroscopy measurement of ∼ 190). We use HPF to perform transmission spectroscopy of TOI-3757 b using the helium 10830 Å line. Doing this, we place an upper limit of 6.9% (with 90% confidence) on the maximum depth of the absorption from the metastable transition of He at ∼10830 Å, which can help constraint the atmospheric mass-loss rate in this energy-limited regime.

Published
2022
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16. TOI-5344 b: A Saturn-like Planet Orbiting a Super-solar Metallicity M0 Dwarf

Author

Te Han, Paul Robertson, Shubham Kanodia, Caleb Cañas, Andrea S. J. Lin, Gumundur Stefánsson, Jessica E. Libby-Roberts, Alexander Larsen, Henry A. Kobulnicky, Suvrath Mahadevan, Chad F. Bender, William D. Cochran, Michael Endl, Mark E. Everett, Arvind F. Gupta, Samuel Halverson, Fred Hearty, Andrew Monson, Joe P. Ninan, Arpita Roy, Christian Schwab, and Ryan C. Terrien

Subjects
Exoplanet systems, Extrasolar gaseous giant planets, M dwarf stars, Astronomy, QB1-991
Abstract

We confirm the planetary nature of TOI-5344 b as a transiting giant exoplanet around an M0-dwarf star. TOI-5344 b was discovered with the Transiting Exoplanet Survey Satellite photometry and confirmed with ground-based photometry (the Red Buttes Observatory 0.6 m telescope), radial velocity (the Habitable-zone Planet Finder), and speckle imaging (the NN-Explore Exoplanet Stellar Speckle Imager). TOI-5344 b is a Saturn-like giant planet ( ρ = 0.80 ${}_{-0.15}^{+0.17}$ g cm ^−3 ) with a planetary radius of 9.7 ± 0.5 R _⊕ (0.87 ± 0.04 R _Jup ) and a planetary mass of ${135}_{-18}^{+17}\ {M}_{\oplus }$ (0.42 ${}_{-0.06}^{+0.05}\ {M}_{\mathrm{Jup}}$ ). It has an orbital period of ${3.792622}_{-0.000010}^{+0.000010}$ days and an orbital eccentricity of ${0.06}_{-0.04}^{+0.07}$ . We measure a high metallicity for TOI-5344 of [Fe/H] = 0.48 ± 0.12, where the high metallicity is consistent with expectations from formation through core accretion. We compare the metallicity of the M-dwarf hosts of giant exoplanets to that of M-dwarf hosts of nongiants (≲8 R _⊕ ). While the two populations appear to show different metallicity distributions, quantitative tests are prohibited by various sample caveats.

Published
2023
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17. Giant Outer Transiting Exoplanet Mass (GOT ’EM) Survey. III. Recovery and Confirmation of a Temperate, Mildly Eccentric, Single-transit Jupiter Orbiting TOI-2010

Author

Christopher R. Mann, Paul A. Dalba, David Lafrenière, Benjamin J. Fulton, Guillaume Hébrard, Isabelle Boisse, Shweta Dalal, Magali Deleuil, Xavier Delfosse, Olivier Demangeon, Thierry Forveille, Neda Heidari, Flavien Kiefer, Eder Martioli, Claire Moutou, Michael Endl, William D. Cochran, Phillip MacQueen, Franck Marchis, Diana Dragomir, Arvind F. Gupta, Dax L. Feliz, Belinda A. Nicholson, Carl Ziegler, Steven Villanueva Jr., Jason Rowe, Geert Jan Talens, Daniel Thorngren, Daryll LaCourse, Tom Jacobs, Andrew W. Howard, Allyson Bieryla, David W. Latham, Markus Rabus, Tara Fetherolf, Coel Hellier, Steve B. Howell, Peter Plavchan, Michael Reefe, Deven Combs, Michael Bowen, Justin Wittrock, George R. Ricker, S. Seager, Joshua N. Winn, Jon M. Jenkins, Thomas Barclay, David Watanabe, Karen A. Collins, Jason D. Eastman, and Eric B. Ting

Subjects
Exoplanet astronomy, Exoplanet systems, Exoplanet dynamics, Exoplanet detection methods, Astronomy, QB1-991
Abstract

Large-scale exoplanet surveys like the Transiting Exoplanet Survey Satellite (TESS) mission are powerful tools for discovering large numbers of exoplanet candidates. Single-transit events are commonplace within the resulting candidate list due to the unavoidable limitation of the observing baseline. These single-transit planets often remain unverified due to their unknown orbital periods and consequent difficulty in scheduling follow-up observations. In some cases, radial velocity (RV) follow up can constrain the period enough to enable a future targeted transit detection. We present the confirmation of one such planet: TOI-2010 b. Nearly three years of RV coverage determined the period to a level where a broad window search could be undertaken with the Near-Earth Object Surveillance Satellite, detecting an additional transit. An additional detection in a much later TESS sector solidified our final parameter estimation. We find TOI-2010 b to be a Jovian planet ( M _P = 1.29 M _Jup , R _P = 1.05 R _Jup ) on a mildly eccentric orbit ( e = 0.21) with a period of P = 141.83403 days. Assuming a simple model with no albedo and perfect heat redistribution, the equilibrium temperature ranges from about 360 to 450 K from apastron to periastron. Its wide orbit and bright host star ( V = 9.85) make TOI-2010 b a valuable test bed for future low-insolation atmospheric analysis.

Published
2023
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18. Stable Fiber-illumination for Extremely Precise Radial Velocities with NEID

Author

Shubham Kanodia, Andrea S. J. Lin, Emily Lubar, Samuel Halverson, Suvrath Mahadevan, Chad F. Bender, Sarah E. Logsdon, Lawrence W. Ramsey, Joe P. Ninan, Gumundur Stefánsson, Andrew Monson, Christian Schwab, Arpita Roy, Leonardo A. Paredes, Eli Golub, Jesus Higuera, Jessica Klusmeyer, William McBride, Cullen Blake, Scott A. Diddams, Fabien Grisé, Arvind F. Gupta, Fred Hearty, Michael W. McElwain, Jayadev Rajagopal, Paul Robertson, and Ryan C. Terrien

Subjects
Exoplanets, Radial velocity, Astronomical instrumentation, Spectrometers, Astronomy, QB1-991
Abstract

NEID is a high-resolution red–optical precision radial velocity (RV) spectrograph recently commissioned at the WIYN 3.5 m telescope at Kitt Peak National Observatory, Arizona, USA. NEID has an extremely stable environmental control system, and spans a wavelength range of 380–930 nm with two observing modes: a High Resolution mode at R ∼ 112,000 for maximum RV precision, and a High Efficiency mode at R ∼ 72,000 for faint targets. In this paper we present a detailed description of the components of NEID’s optical fiber feed, which include the instrument, exposure meter, calibration system, and telescope fibers. Many parts of the optical fiber feed can lead to uncalibratable RV errors, which cannot be corrected for using a stable wavelength reference source. We show how these errors directly cascade down to performance requirements on the fiber feed and the scrambling system. We detail the design, assembly, and testing of each component. Designed and built from the bottom-up with a single-visit instrument precision requirement of 27 cm s ^−1 , close attention is paid to the error contribution from each NEID subsystem. Finally, we include the lab and on-sky tests performed during instrument commissioning to test the illumination stability, and discuss the path to achieving the instrumental stability required to search for a true Earth twin around a solar-type star.

Published
2023
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19. TOI-3785 b: A Low-density Neptune Orbiting an M2-dwarf Star

Author

Luke C. Powers, Jessica Libby-Roberts, Andrea S. J. Lin, Caleb I. Cañas, Shubham Kanodia, Suvrath Mahadevan, Joe P. Ninan, Guđmundur Stefánsson, Arvind F. Gupta, Sinclaire Jones, Henry A. Kobulnicky, Andrew Monson, Brock A. Parker, Tera N. Swaby, Chad F. Bender, William D. Cochran, Leslie Hebb, Andrew J. Metcalf, Paul Robertson, Christian Schwab, John Wisniewski, and Jason T. Wright

Subjects
Exoplanet astronomy, Radial velocity, Transits, M dwarf stars, Astronomy, QB1-991
Abstract

Using both ground-based transit photometry and high-precision radial velocity spectroscopy, we confirm the planetary nature of TOI-3785 b. This transiting Neptune orbits an M2-Dwarf star with a period of ∼4.67 days, a planetary radius of 5.14 ± 0.16 R _⊕ , a mass of ${14.95}_{-3.92}^{+4.10}$ M _⊕ , and a density of $\rho ={0.61}_{-0.17}^{+0.18}$ g cm ^−3 . TOI-3785 b belongs to a rare population of Neptunes (4 R _⊕ < R _p < 7 R _⊕ ) orbiting cooler, smaller M-dwarf host stars, of which only ∼10 have been confirmed. By increasing the number of confirmed planets, TOI-3785 b offers an opportunity to compare similar planets across varying planetary and stellar parameter spaces. Moreover, with a high-transmission spectroscopy metric of ∼150 combined with a relatively cool equilibrium temperature of T _eq = 582 ± 16 K and an inactive host star, TOI-3785 b is one of the more promising low-density M-dwarf Neptune targets for atmospheric follow up. Future investigation into atmospheric mass-loss rates of TOI-3785 b may yield new insights into the atmospheric evolution of these low-mass gas planets around M dwarfs.

Published
2023
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20. TOI-3984 A b and TOI-5293 A b: Two Temperate Gas Giants Transiting Mid-M Dwarfs in Wide Binary Systems

Author

Caleb I. Cañas, Shubham Kanodia, Jessica Libby-Roberts, Andrea S. J. Lin, Maria Schutte, Luke Powers, Sinclaire Jones, Andrew Monson, Songhu Wang, Guđmundur Stefánsson, William D. Cochran, Paul Robertson, Suvrath Mahadevan, Adam F. Kowalski, John Wisniewski, Brock A. Parker, Alexander Larsen, Franklin A. L. Chapman, Henry A. Kobulnicky, Arvind F. Gupta, Mark E. Everett, Bryan Edward Penprase, Gregory Zeimann, Corey Beard, Chad F. Bender, Knicole D. Colón, Scott A. Diddams, Connor Fredrick, Samuel Halverson, Joe P. Ninan, Lawrence W. Ramsey, Arpita Roy, and Christian Schwab

Subjects
Exoplanet systems, Extrasolar gaseous giant planets, Astronomy, QB1-991
Abstract

We confirm the planetary nature of two gas giants discovered by TESS to transit M dwarfs with stellar companions at wide separations. TOI-3984 A ( J = 11.93) is an M4 dwarf hosting a short-period (4.353326 ± 0.000005 days) gas giant ( M _p = 0.14 ± 0.03 M _J and R _p = 0.71 ± 0.02 R _J ) with a wide-separation white dwarf companion. TOI-5293 A ( J = 12.47) is an M3 dwarf hosting a short-period (2.930289 ± 0.000004 days) gas giant ( M _p = 0.54 ± 0.07 M _J and R _p = 1.06 ± 0.04 R _J ) with a wide-separation M dwarf companion. We characterize both systems using a combination of ground- and space-based photometry, speckle imaging, and high-precision radial velocities from the Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b ( T _eq = 563 ± 15 K and $\mathrm{TSM}={138}_{-27}^{+29}$ ) and TOI-5293 A b ( ${T}_{\mathrm{eq}}={675}_{-30}^{+42}$ K and TSM = 92 ± 14) are two of the coolest gas giants among the population of hot Jupiter–sized gas planets orbiting M dwarfs and are favorable targets for atmospheric characterization of temperate gas giants and 3D obliquity measurements to probe system architecture and migration scenarios.

Published
2023
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21. An In-depth Look at TOI-3884b: A Super-Neptune Transiting an M4Dwarf with Persistent Starspot Crossings

Author

Jessica E. Libby-Roberts, Maria Schutte, Leslie Hebb, Shubham Kanodia, Caleb I. Cañas, Guðmundur Stefánsson, Andrea S. J. Lin, Suvrath Mahadevan, Winter Parts(they/them), Luke Powers, John Wisniewski, Chad F. Bender, William D. Cochran, Scott A. Diddams, Mark E. Everett, Arvind F. Gupta, Samuel Halverson, Henry A. Kobulnicky, Adam F. Kowalski, Alexander Larsen, Andrew Monson, Joe P. Ninan, Brock A. Parker, Lawrence W. Ramsey, Paul Robertson, Christian Schwab, Tera N. Swaby, and Ryan C. Terrien

Subjects
Exoplanet astronomy, Exoplanets, Exoplanet detection methods, Starspots, Astronomy, QB1-991
Abstract

We perform an in-depth analysis of the recently validated TOI-3884 system, an M4-dwarf star with a transiting super-Neptune. Using high-precision light curves obtained with the 3.5 m Apache Point Observatory and radial velocity observations with the Habitable-zone Planet Finder, we derive a planetary mass of ${32.6}_{-7.4}^{+7.3}\,{M}_{\oplus }$ and radius of 6.4 ± 0.2 R _⊕ . We detect a distinct starspot crossing event occurring just after ingress and spanning half the transit for every transit. We determine this spot feature to be wavelength dependent with the amplitude and duration evolving slightly over time. Best-fit starspot models show that TOI-3884b possesses a misaligned ( λ = 75° ± 10°) orbit that crosses a giant pole spot. This system presents a rare opportunity for studies into the nature of both a misaligned super-Neptune and spot evolution on an active mid-M dwarf.

Published
2023
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22. TOI-5375 B: A Very Low Mass Star at the Hydrogen-burning Limit Orbiting an Early M-type Star

Author

Mika Lambert, Chad F. Bender, Shubham Kanodia, Caleb I. Cañas, Andrew Monson, Gudmundur Stefánsson, William D. Cochran, Mark E. Everett, Arvind F. Gupta, Fred Hearty, Henry A. Kobulnicky, Jessica E. Libby-Roberts, Andrea S. J. Lin, Suvrath Mahadevan, Joe P. Ninan, Brock A. Parker, Paul Robertson, Christian Schwab, and Ryan C. Terrien

Subjects
Binary stars, Low mass stars, Astronomy, QB1-991
Abstract

The Transiting Exoplanet Survey Satellite (TESS) mission detected a companion orbiting TIC 71268730, categorized it as a planet candidate, and designated the system TOI-5375. Our follow-up analysis using radial-velocity data from the Habitable-zone Planet Finder, photometric data from Red Buttes Observatory, and speckle imaging with NN-EXPLORE Exoplanet Stellar Speckle Imager determined that the companion is a very low mass star near the hydrogen-burning mass limit with a mass of 0.080 ± 0.002 M _☉ (83.81 ± 2.10 M _J ), a radius of ${0.1114}_{-0.0050}^{+0.0048}{R}_{\odot }$ (1.0841 ${}_{0.0487}^{0.0467}{R}_{J}$ ), and brightness temperature of 2600 ± 70 K. This object orbits with a period of 1.721553 ± 0.000001 days around an early M dwarf star (0.62 ± 0.016 M _☉ ). TESS photometry shows regular variations in the host star’s TESS light curve, which we interpreted as an activity-induced variation of ∼2%, and used this variability to measure the host star’s stellar rotation period of ${1.9716}_{-0.0083}^{+0.0080}$ days. The TOI-5375 system provides tight constraints on stellar models of low-mass stars at the hydrogen-burning limit and adds to the population in this important region.

Published
2023
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23. Impact of Correlated Noise on the Mass Precision of Earth-analog Planets in Radial Velocity Surveys

Author

Jacob K. Luhn, Eric B. Ford, Zhao Guo, Christian Gilbertson, Patrick Newman, Peter Plavchan, Jennifer A. Burt, Johanna Teske, and Arvind F. Gupta

Subjects
Exoplanet detection methods, Time series analysis, Stellar oscillations, Stellar granulation, Stellar activity, Radial velocity, Astronomy, QB1-991
Abstract

Characterizing the masses and orbits of near-Earth-mass planets is crucial for interpreting observations from future direct imaging missions (e.g., HabEx, LUVOIR). Therefore, the Exoplanet Science Strategy report recommended further research so future extremely precise radial velocity surveys could contribute to the discovery and/or characterization of near-Earth-mass planets in the habitable zones of nearby stars prior to the launch of these future imaging missions. Newman et al. (2023) simulated such 10 yr surveys under various telescope architectures, demonstrating they can precisely measure the masses of potentially habitable Earth-mass planets in the absence of stellar variability. Here, we investigate the effect of stellar variability on the signal-to-noise ratio (S/N) of the planet mass measurements in these simulations. We find that correlated noise due to active regions has the largest effect on the observed mass S/N, reducing the S/N by a factor of ∼5.5 relative to the no-variability scenario; granulation reduces by a factor of ∼3, while p-mode oscillations has little impact on the proposed survey strategies. We show that in the presence of correlated noise, 5 cm s ^−1 instrumental precision offers little improvement over 10 cm s ^−1 precision, highlighting the need to mitigate astrophysical variability. With our noise models, extending the survey to 15 yr doubles the number of Earth-analogs with mass S/N > 10, and reaching this threshold for any Earth-analog orbiting a star >0.76 M _⊙ in a 10 yr survey would require an increase in the number of observations per star from that in Newman et al. (2023).

Published
2023
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24. TOI-5205b: A Short-period Jovian Planet Transiting a Mid-M Dwarf

Author

Shubham Kanodia, Suvrath Mahadevan, Jessica Libby-Roberts, Gudmundur Stefansson, Caleb I. Cañas, Anjali A. A. Piette, Alan Boss, Johanna Teske, John Chambers, Greg Zeimann, Andrew Monson, Paul Robertson, Joe P. Ninan, Andrea S. J. Lin, Chad F. Bender, William D. Cochran, Scott A. Diddams, Arvind F. Gupta, Samuel Halverson, Suzanne Hawley, Henry A. Kobulnicky, Andrew J. Metcalf, Brock A. Parker, Luke Powers, Lawrence W. Ramsey, Arpita Roy, Christian Schwab, Tera N. Swaby, Ryan C. Terrien, and John Wisniewski

Subjects
Radial velocity, M dwarf stars, Extrasolar gaseous giant planets, Transits, Astronomy, QB1-991
Abstract

We present the discovery of TOI-5205b, a transiting Jovian planet orbiting a solar metallicity M4V star, which was discovered using Transiting Exoplanet Survey Satellite photometry and then confirmed using a combination of precise radial velocities, ground-based photometry, spectra, and speckle imaging. TOI-5205b has one of the highest mass ratios for M-dwarf planets, with a mass ratio of almost 0.3%, as it orbits a host star that is just 0.392 ± 0.015 M _⊙ . Its planetary radius is 1.03 ± 0.03 R _J , while the mass is 1.08 ± 0.06 M _J . Additionally, the large size of the planet orbiting a small star results in a transit depth of ∼7%, making it one of the deepest transits of a confirmed exoplanet orbiting a main-sequence star. The large transit depth makes TOI-5205b a compelling target to probe its atmospheric properties, as a means of tracing the potential formation pathways. While there have been radial-velocity-only discoveries of giant planets around mid-M dwarfs, this is the first transiting Jupiter with a mass measurement discovered around such a low-mass host star. The high mass of TOI-5205b stretches conventional theories of planet formation and disk scaling relations that cannot easily recreate the conditions required to form such planets.

Published
2023
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25. Noninvasive Monitoring of Simulated Hemorrhage and Whole Blood Resuscitation

Author

Jay F. Gupta, Saaid H. Arshad, Brian A. Telfer, Eric J. Snider, and Victor A. Convertino

Subjects
signal processing, machine learning, hemorrhage, resuscitation, prehospital, prolonged field care, Biotechnology, TP248.13-248.65
Abstract

Hemorrhage is the leading cause of preventable death from trauma. Accurate monitoring of hemorrhage and resuscitation can significantly reduce mortality and morbidity but remains a challenge due to the low sensitivity of traditional vital signs in detecting blood loss and possible hemorrhagic shock. Vital signs are not reliable early indicators because of physiological mechanisms that compensate for blood loss and thus do not provide an accurate assessment of volume status. As an alternative, machine learning (ML) algorithms that operate on an arterial blood pressure (ABP) waveform have been shown to provide an effective early indicator. However, these ML approaches lack physiological interpretability. In this paper, we evaluate and compare the performance of ML models trained on nine ABP-derived features that provide physiological insight, using a database of 13 human subjects from a lower-body negative pressure (LBNP) model of progressive central hypovolemia and subsequent progressive restoration to normovolemia (i.e., simulated hemorrhage and whole blood resuscitation). Data were acquired at multiple repressurization rates for each subject to simulate varying resuscitation rates, resulting in 52 total LBNP collections. This work is the first to use a single ABP-based algorithm to monitor both simulated hemorrhage and resuscitation. A gradient-boosted regression tree model trained on only the half-rise to dicrotic notch (HRDN) feature achieved a root-mean-square error (RMSE) of 13%, an R2 of 0.82, and area under the receiver operating characteristic curve of 0.97 for detecting decompensation. This single-feature model’s performance compares favorably to previously reported results from more-complex black box machine learning models. This model further provides physiological insight because HRDN represents an approximate measure of the delay between the ABP ejected and reflected wave and therefore is an indication of cardiac and peripheral vascular mechanisms that contribute to the compensatory response to blood loss and replacement.

Published
2022
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26. TOI-1231 b: A Temperate, Neptune-sized Planet Transiting the Nearby M3 Dwarf NLTT 24399

Author

Jennifer A. Burt, Diana Dragomir, Paul Mollière, Allison Ann Youngblood, Antonio García Muñoz, John McCann, Laura Kreidberg, Chelsea X. Huang, Karen A. Collins, Jason D. Eastman, Lyu Abe, Jose M. Almenara, Ian J. M. Crossfield, Carl Ziegler, Joseph E. Rodriguez, Eric E. Mamajek, Keivan G. Stassun, Samuel P. Halverson, Steven Villanueva Jr, R. Paul Butler, Sharon Xuesong Wang, Richard P Schwarz, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Abdelkrim Agabi, Xavier Bonfils, David Ciardi, Marion Cointepas, Jeffrey D. Crane, Nicolas Crouzet, Georgina Dransfield, Fabo Feng, Elise Furlan, Tristan Guillot, Arvind F. Gupta, Steve B. Howell, Eric L. N. Jensen, Nicholas Law, Andrew W. Mann, Wenceslas Marie-Sainte, Rachel A. Matson, Elisabeth C. Matthews, Djamel Mékarnia, Joshua Pepper, Nic Scott, Stephen A. Shectman, Joshua E. Schlieder, François-Xavier Schmider, Daniel J. Stevens, Johanna K. Teske, Amaury H. M. J. Triaud, David Charbonneau, Zachory K. Berta-Thompson, Christopher J. Burke, Tansu Daylan, Thomas Barclay, Bill Wohler, and C. E. Brasseur

Subjects
Astronomy, Astrophysics
Abstract

We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby (d = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite and followed up with observations from the Las Cumbres Observatory and the Antarctica Search for Transiting ExoPlanets program. Combining the photometric data sets, we find that the newly discovered planet has a radius of 3.65(+0.16,-0.15)Rꚛ and an orbital period of 24.246 days. Radial velocity measurements obtained with the Planet Finder Spectrograph on the Magellan Clay telescope confirm the existence of the planet and lead to a mass measurement of 15.5 ± 3.3 Mꚛ. With an equilibrium temperature of just 330 K, TOI-1231 b is one of the coolest small planets accessible for atmospheric studies thus far, and its host star's bright near-infrared brightness (J = 8.88, Ks = 8.07) makes it an exciting target for the Hubble Space Telescope and the James Webb Space Telescope. Future atmospheric observations would enable the first comparative planetology efforts in the 250–350 K temperature regime via comparisons with K2-18 b. Furthermore, TOI-1231's high systemic radial velocity (70.5 km/s) may allow for the detection of low-velocity hydrogen atoms escaping the planet by Doppler, shifting the H i Lyα stellar emission away from the geocoronal and interstellar medium absorption features.

Published
2021
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27. TOI-3714 b and TOI-3629 b: Two Gas Giants Transiting M Dwarfs Confirmed with the Habitable-zone Planet Finder and NEID

Author

Caleb I. Cañas, Shubham Kanodia, Chad F. Bender, Suvrath Mahadevan, Guđhmundur Stefánsson, William D. Cochran, Andrea S. J. Lin, Hsiang-Chih Hwang, Luke Powers, Andrew Monson, Elizabeth M. Green, Brock A. Parker, Tera N. Swaby, Henry A. Kobulnicky, John Wisniewski, Arvind F. Gupta, Mark E. Everett, Sinclaire Jones, Benjamin Anjakos, Corey Beard, Cullen H. Blake, Scott A. Diddams, Zehao 泽 浩 Dong 董, Connor Fredrick, Elnaz Hakemiamjad, Leslie Hebb, Jessica E. Libby-Roberts, Sarah E. Logsdon, Michael W. McElwain, Andrew J. Metcalf, Joe P. Ninan, Jayadev Rajagopal, Lawrence W. Ramsey, Paul Robertson, Arpita Roy, Jacob Ruhle, Christian Schwab, Ryan C. Terrien, and Jason T. Wright

Published
2022
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28. A Close-in Puffy Neptune with Hidden Friends: The Enigma of TOI 620

Author

Michael A. Reefe, Rafael Luque, Eric Gaidos, Corey Beard, Peter P. Plavchan, Marion Cointepas, Bryson L. Cale, Enric Palle, Hannu Parviainen, Dax L. Feliz, Jason Eastman, Keivan Stassun, Jonathan Gagné, Jon M. Jenkins, Patricia T. Boyd, Richard C. Kidwell, Scott McDermott, Karen A. Collins, William Fong, Natalia Guerrero, Jose-Manuel Almenara-Villa, Jacob Bean, Charles A. Beichman, John Berberian, Allyson Bieryla, Xavier Bonfils, François Bouchy, Madison Brady, Edward M. Bryant, Luca Cacciapuoti, Caleb I. Cañas, David R. Ciardi, Kevin I. Collins, Ian J. M. Crossfield, Courtney D. Dressing, Philipp Eigmüller, Mohammed El Mufti, Emma Esparza-Borges, Akihiko Fukui, Peter Gao, Claire Geneser, Crystal L. Gnilka, Erica Gonzales, Arvind F. Gupta, Sam Halverson, Fred Hearty, Steve B. Howell, Jonathan Irwin, Shubham Kanodia, David Kasper, Takanori Kodama, Veselin Kostov, David W. Latham, Monika Lendl, Andrea Lin, John H. Livingston, Jack Lubin, Suvrath Mahadevan, Rachel Matson, Elisabeth Matthews, Felipe Murgas, Norio Narita, Patrick Newman, Joe Ninan, Ares Osborn, Samuel N. Quinn, Paul Robertson, Arpita Roy, Joshua Schlieder, Christian Schwab, Andreas Seifahrt, Gareth D. Smith, Ahmad Sohani, Guðmundur Stefánsson, Daniel Stevens, Julian Stürmer, Angelle Tanner, Ryan Terrien, Johanna Teske, David Vermilion, Sharon X. Wang, Justin Wittrock, Jason T. Wright, Mathias Zechmeister, and Farzaneh Zohrabi

Published
2022
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29. Target Prioritization and Observing Strategies for the NEID Earth Twin Survey

Author

Arvind F. Gupta, Jason T. Wright, Paul Robertson, Samuel Halverson, Jacob Luhn, Arpita Roy, Suvrath Mahadevan, Eric B. Ford, Chad F. Bender, Cullen H. Blake, Fred Hearty, Shubham Kanodia, Sarah E. Logsdon, Michael W. McElwain, Andrew Monson, Joe P. Ninan, Christian Schwab, Guðmundur Stefánsson, and Ryan C. Terrien

Subjects
Astronomy, Astrophysics
Abstract

NEID is a high-resolution optical spectrograph on the WIYN 3.5 m telescope at Kitt Peak National Observatory and will soon join the new generation of extreme precision radial velocity instruments in operation around the world. We plan to use the instrument to conduct the NEID Earth Twin Survey (NETS) over the course of the next 5 years, collecting hundreds of observations of some of the nearest and brightest stars in an effort to probe the regime of Earth-mass exoplanets. Even if we take advantage of the extreme instrumental precision conferred by NEID, it will be difficult to disentangle the weak (~10 cm/s) signals induced by such low-mass, long-period exoplanets from stellar noise for all but the quietest host stars. In this work, we present a set of quantitative selection metrics which we use to identify an initial NETS target list consisting of stars conducive to the detection of exoplanets in the regime of interest. We also outline a set of observing strategies with which we aim to mitigate uncertainty contributions from intrinsic stellar variability and other sources of noise.

Published
2021
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30. AI-Enabled, Ultrasound-Guided Handheld Robotic Device for Femoral Vascular Access

Author

Laura J. Brattain, Theodore T. Pierce, Lars A. Gjesteby, Matthew R. Johnson, Nancy D. DeLosa, Joshua S. Werblin, Jay F. Gupta, Arinc Ozturk, Xiaohong Wang, Qian Li, Brian A. Telfer, and Anthony E. Samir

Subjects
vascular access, femoral vein, medical robotics, artificial intelligence, deep learning, Biotechnology, TP248.13-248.65
Abstract

Hemorrhage is a leading cause of trauma death, particularly in prehospital environments when evacuation is delayed. Obtaining central vascular access to a deep artery or vein is important for administration of emergency drugs and analgesics, and rapid replacement of blood volume, as well as invasive sensing and emerging life-saving interventions. However, central access is normally performed by highly experienced critical care physicians in a hospital setting. We developed a handheld AI-enabled interventional device, AI-GUIDE (Artificial Intelligence Guided Ultrasound Interventional Device), capable of directing users with no ultrasound or interventional expertise to catheterize a deep blood vessel, with an initial focus on the femoral vein. AI-GUIDE integrates with widely available commercial portable ultrasound systems and guides a user in ultrasound probe localization, venous puncture-point localization, and needle insertion. The system performs vascular puncture robotically and incorporates a preloaded guidewire to facilitate the Seldinger technique of catheter insertion. Results from tissue-mimicking phantom and porcine studies under normotensive and hypotensive conditions provide evidence of the technique’s robustness, with key performance metrics in a live porcine model including: a mean time to acquire femoral vein insertion point of 53 ± 36 s (5 users with varying experience, in 20 trials), a total time to insert catheter of 80 ± 30 s (1 user, in 6 trials), and a mean number of 1.1 (normotensive, 39 trials) and 1.3 (hypotensive, 55 trials) needle insertion attempts (1 user). These performance metrics in a porcine model are consistent with those for experienced medical providers performing central vascular access on humans in a hospital.

Published
2021
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31. The TESS-Keck Survey. I. A Warm Sub-Saturn-mass Planet and a Caution about Stray Light in TESS Cameras

Author

Paul A. Dalba, Arvind F. Gupta, Joseph E. Rodriguez, Diana Dragomir, Chelsea X. Huang, Stephen R. Kane, Samuel N. Quinn, Allyson Bieryla, Gilbert A. Esquerdo, Benjamin J. Fulton, Nicholas Scarsdale, Natalie M. Batalha, Corey Beard, Aida Behmard, Ashley Chontos, Ian J. M. Crossfield, Courtney D. Dressing, Steven Giacalone, Michelle L. Hill, Lea A. Hirsch, Andrew W. Howard, Daniel Huber, Howard Isaacson, Molly Kosiarek, Jack Lubin, Andrew W. Mayo, Teo Mocnik, Joseph M. Akana Murphy, Erik A. Petigura, Paul Robertson, Lee J. Rosenthal, Arpita Roy, Ryan A. Rubenzahl, Judah Van Zandt, Lauren M. Weiss, Emil Knudstrup, Mads F. Andersen, Frank Grundahl, Xinyu Yao, Joshua Pepper, Steven Villanueva Jr, David R. Ciardi, Ryan Cloutier, Thomas Lee Jacobs, Martti H. Kristiansen, Daryll M. LaCourse, Monika Lendl, Hugh P. Osborn, Enric Palle, Keivan G. Stassun, Daniel J. Stevens, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Douglas A. Caldwell, Tansu Daylan, William Fong, Robert F. Goeke, Mark E. Rose, Pamela Rowden, Joshua E. Schlieder, Jeffrey C. Smith, and Andrew Vanderburg

Subjects
Astronomy, Astrophysics
Abstract

We report the detection of a Saturn-size exoplanet orbiting HD 332231 (TOI 1456) in light curves from the Transiting Exoplanet Survey Satellite (TESS). HD 332231—an F8 dwarf star with a V-band magnitude of 8.56—was observed by TESS in Sectors 14 and 15. We detect a single-transit event in the Sector 15 presearch data conditioning (PDC) light curve. We obtain spectroscopic follow-up observations of HD 332231 with the Automated Planet Finder, Keck I, and SONG telescopes. The orbital period we infer from radial velocity (RV) observations leads to the discovery of another transit in Sector 14 that was masked by PDC due to scattered light contamination. A joint analysis of the transit and RV data confirms the planetary nature of HD 332231 b, a Saturn-size (0.867 (+0.027,-0.025 R(J)), sub-Saturn-mass (0.244 ± 0.021M(J)) exoplanet on a 18.71 day circular orbit. The low surface gravity of HD 332231 b and the relatively low stellar flux it receives make it a compelling target for transmission spectroscopy. Also, the stellar obliquity is likely measurable via the Rossiter–McLaughlin effect, an exciting prospect given the 0.14 au orbital separation of HD 332231 b. The spectroscopic observations do not provide substantial evidence for any additional planets in the HD 332231 system, but continued RV monitoring is needed to further characterize this system. We also predict that the frequency and duration of masked data in the PDC light curves for TESS Sectors 14–16 could hide transits of some exoplanets with orbital periods between 10.5 and 17.5 days.

Published
2020
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32. An Eccentric Brown Dwarf Eclipsing an M dwarf

Author

Caleb I. Cañas, Suvrath Mahadevan, Chad F. Bender, Noah Isaac Salazar Rivera, Andrew Monson, Corey Beard, Jack Lubin, Paul Robertson, Arvind F. Gupta, William D. Cochran, Connor Fredrick, Fred Hearty, Sinclaire Jones, Shubham Kanodia, Andrea S. J. Lin, Joe P. Ninan, Lawrence W. Ramsey, Christian Schwab, and Guđmundur Stefánsson

Published
2022
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33. TOI-532b: The Habitable-zone Planet Finder confirms a Large Super Neptune in the Neptune Desert orbiting a metal-rich M-dwarf host

Author

Shubham Kanodia, Gudmundur Stefansson, Caleb I. Cañas, Marissa Maney, Andrea S. J. Lin, Joe P. Ninan, Sinclaire Jones, Andrew Monson, Brock A. Parker, Henry A. Kobulnicky, Jason Rothenberg, Corey Beard, Jack Lubin, Paul Robertson, Arvind F. Gupta, Suvrath Mahadevan, William D. Cochran, Chad F. Bender, Scott A. Diddams, Connor Fredrick, Samuel Halverson, Suzanne Hawley, Fred Hearty, Leslie Hebb, Ravi Kopparapu, Andrew J. Metcalf, Lawrence W. Ramsey, Arpita Roy, Christian Schwab, Maria Schutte, Ryan C. Terrien, John Wisniewski, and Jason T. Wright

Published
2021
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34. Electrophysiological properties and projections of lateral hypothalamic parvalbumin positive neurons.

Author

Alexandre Kisner, Julia E Slocomb, Sarah Sarsfield, Maria Laura Zuccoli, Justin Siemian, Jay F Gupta, Arvind Kumar, and Yeka Aponte

Subjects
Medicine, Science
Abstract

Cracking the cytoarchitectural organization, activity patterns, and neurotransmitter nature of genetically-distinct cell types in the lateral hypothalamus (LH) is fundamental to develop a mechanistic understanding of how activity dynamics within this brain region are generated and operate together through synaptic connections to regulate circuit function. However, the precise mechanisms through which LH circuits orchestrate such dynamics have remained elusive due to the heterogeneity of the intermingled and functionally distinct cell types in this brain region. Here we reveal that a cell type in the mouse LH identified by the expression of the calcium-binding protein parvalbumin (PVALB; LHPV) is fast-spiking, releases the excitatory neurotransmitter glutamate, and sends long range projections throughout the brain. Thus, our findings challenge long-standing concepts that define neurons with a fast-spiking phenotype as exclusively GABAergic. Furthermore, we provide for the first time a detailed characterization of the electrophysiological properties of these neurons. Our work identifies LHPV neurons as a novel functional component within the LH glutamatergic circuitry.

Published
2018
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35. Real-time exposure control and instrument operation with the NEID spectrograph GUI

Author

Arvind F. Gupta, Chad F. Bender, Joe P. Ninan, Sarah E. Logsdon, Shubham Kanodia, Eli Golub, Jesus Higuera, Jessica Klusmeyer, Samuel P. Halverson, Suvrath Mahadevan, Michael W. McElwain, Christian Schwab, Gudmundur Stefansson, Paul M. Robertson, Arpita Roy, Ryan C. Terrien, and Jason T. Wright

Subjects
FOS: Physical sciences, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM)
Abstract

The NEID spectrograph on the WIYN 3.5-m telescope at Kitt Peak has completed its first full year of science operations and is reliably delivering sub-m/s precision radial velocity measurements. The NEID instrument control system uses the TIMS package (Bender et al. 2016), which is a client-server software system built around the twisted python software stack. During science observations, interaction with the NEID spectrograph is handled through a pair of graphical user interfaces (GUIs), written in PyQT, which wrap the underlying instrument control software and provide straightforward and reliable access to the instrument. Here, we detail the design of these interfaces and present an overview of their use for NEID operations. Observers can use the NEID GUIs to set the exposure time, signal-to-noise ratio (SNR) threshold, and other relevant parameters for observations, configure the calibration bench and observing mode, track or edit observation metadata, and monitor the current state of the instrument. These GUIs facilitate automatic spectrograph configuration and target ingestion from the nightly observing queue, which improves operational efficiency and consistency across epochs. By interfacing with the NEID exposure meter, the GUIs also allow observers to monitor the progress of individual exposures and trigger the shutter on user-defined SNR thresholds. In addition, inset plots of the instantaneous and cumulative exposure meter counts as each observation progresses allow for rapid diagnosis of changing observing conditions as well as guiding failure and other emergent issues., Published in Proceedings of the SPIE Astronomical Telescopes + Instrumentation, 2022; 12 pages

Published
2022

36. TOI-1231 b: A Temperate, Neptune-Sized Planet Transiting the Nearby M3 Dwarf NLTT 24399

Author

Wenceslas Marie-Sainte, Xavier Bonfils, Ian J. M. Crossfield, Christopher J. Burke, François-Xavier Schmider, Fabo Feng, Stephen A. Shectman, Antonio García Muñoz, Tansu Daylan, Elisabeth Matthews, Keivan G. Stassun, Diana Dragomir, Zachory K. Berta-Thompson, Abdelkrim Agabi, Rachel A. Matson, Nicolas Crouzet, Bill Wohler, Roland Vanderspek, Jennifer Burt, Johanna Teske, Sara Seager, C. E. Brasseur, David Charbonneau, Djamel Mékarnia, George R. Ricker, Amaury H. M. J. Triaud, Chelsea X. Huang, John McCann, Joshua Pepper, Jason D. Eastman, Allison Youngblood, Jeffrey D. Crane, Eric E. Mamajek, Lyu Abe, Karen A. Collins, Carl Ziegler, Tristan Guillot, Laura Kreidberg, Paul Mollière, David R. Ciardi, Daniel J. Stevens, Marion Cointepas, David W. Latham, Richard P. Schwarz, Andrew W. Mann, Joshua E. Schlieder, Joshua N. Winn, Georgina Dransfield, Elise Furlan, Eric L. N. Jensen, Steven Villanueva, Joseph E. Rodriguez, Jon M. Jenkins, Steve B. Howell, Sharon X. Wang, Arvind F. Gupta, Nicholas M. Law, Nic Scott, Samuel Halverson, R. Paul Butler, J. M. Almenara, Thomas Barclay, MIT Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology (MIT), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, Technische Universität Berlin (TU), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015 - 2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Smithsonian Institution-Harvard University [Cambridge], Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.ASTR.EP]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Earth and Planetary Astrophysics [astro-ph.EP], Radial velocity (1332), FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, 010309 optics, Telescope, Neptune, law, Planet, Observatory, 0103 physical sciences, Transit photometry (1709), Astrophysics::Solar and Stellar Astrophysics, 010303 astronomy & astrophysics, ComputingMilieux_MISCELLANEOUS, Astrophysics::Galaxy Astrophysics, Earth and Planetary Astrophysics (astro-ph.EP), Physics, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Exoplanets (498), Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Orbital period, Exoplanet, Radial velocity, Planetary science, 13. Climate action, Space and Planetary Science, [SDU]Sciences of the Universe [physics], Planetary system formation (1257), Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby ($d$ = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099). The planet was detected using photometric data from the Transiting Exoplanet Survey Satellite and followed up with observations from the Las Cumbres Observatory and the Antarctica Search for Transiting ExoPlanets program. Combining the photometric data sets, we find that the newly discovered planet has a radius of 3.65$^{+0.16}_{-0.15}$ R$_{\oplus}$, and an orbital period of 24.246 days. Radial velocity measurements obtained with the Planet Finder Spectrograph on the Magellan Clay telescope confirm the existence of the planet and lead to a mass measurement of 15.5$\pm$3.3 M$_{\oplus}$. With an equilibrium temperature of just 330K TOI-1231 b is one of the coolest small planets accessible for atmospheric studies thus far, and its host star's bright NIR brightness (J=8.88, K$_{s}$=8.07) make it an exciting target for HST and JWST. Future atmospheric observations would enable the first comparative planetology efforts in the 250-350 K temperature regime via comparisons with K2-18 b. Furthermore, TOI-1231's high systemic radial velocity (70.5 k\ms) may allow for the detection of low-velocity hydrogen atoms escaping the planet by Doppler shifting the H I Ly-alpha stellar emission away from the geocoronal and ISM absorption features., 20 pages, 9 figures. Accepted for publication in The Astronomical Journal

Published
2021

37. TOI-1696 and TOI-2136: Constraining the Masses of Two Mini-Neptunes with the Habitable-Zone Planet Finder

Author

Corey Beard, Paul Robertson, Shubham Kanodia, Jessica Libby-Roberts, Caleb I. Cañas, Arvind F. Gupta, Rae Holcomb, Sinclaire Jones, Henry A. Kobulnicky, Andrea S. J. Lin, Jack Lubin, Marissa Maney, Brock A. Parker, Guðmundur Stefánsson, William D. Cochran, Michael Endl, Leslie Hebb, Suvrath Mahadevan, John Wisniewski, Chad F. Bender, Scott A. Diddams, Mark Everett, Connor Fredrick, Samuel Halverson, Fred Hearty, Andrew J. Metcalf, Andrew Monson, Joe P. Ninan, Arpita Roy, Maria Schutte, Christian Schwab, and Ryan C Terrien

Subjects
Space and Planetary Science, Astronomy and Astrophysics
Abstract

We present the validation of two planets orbiting M dwarfs, TOI-1696b and TOI-2136b. Both planets are mini-Neptunes orbiting nearby stars, making them promising prospects for atmospheric characterization with the James Webb Space Telescope (JWST). We validated the planetary nature of both candidates using high-contrast imaging, ground-based photometry, and near-infrared radial velocities. Adaptive optics images were taken using the ShARCS camera on the 3 m Shane Telescope. Speckle images were taken using the NN-Explore Exoplanet Stellar Speckle Imager on the WIYN 3.5 m telescope. Radii and orbital ephemerides were refined using a combination of the Transiting Exoplanet Survey Satellite, the diffuser-assisted Astrophysical Research Consortium (ARC) Telescope Imaging Camera (ARCTIC) imager on the 3.5 m ARC telescope at Apache Point Observatory, and the 0.6 m telescope at Red Buttes Observatory. We obtained radial velocities using the Habitable-Zone Planet Finder on the 10 m Hobby–Eberly Telescope, which enabled us to place upper limits on the masses of both transiting planets. TOI-1696b (P = 2.5 days; R p = 3.24 R ⊕; M p < 56.6 M ⊕) falls into a sparsely populated region of parameter space considering its host star’s temperature (T eff = 3168 K, M4.5), as planets of its size are quite rare around mid- to late-M dwarfs. On the other hand, TOI-2136b (P = 7.85 days; R p = 2.09 R ⊕; M p < 15.0 M ⊕) is an excellent candidate for atmospheric follow-up with the JWST.

Published
2022

38. Target Prioritization and Observing Strategies for the NEID Earth Twin Survey

Author

Chad F. Bender, Andrew J. Monson, Cullen H. Blake, Michael W. McElwain, Ryan Terrien, Paul Robertson, Samuel Halverson, Sarah E. Logsdon, Suvrath Mahadevan, Arvind F. Gupta, Gudmundur Stefansson, Arpita Roy, Jacob K. Luhn, Shubham Kanodia, Joe P. Ninan, Eric B. Ford, Fred Hearty, Jason T. Wright, and Christian Schwab

Subjects
Prioritization, 010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, law, Observatory, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, Spectrograph, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Earth and Planetary Astrophysics (astro-ph.EP), Physics, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Astronomy and Astrophysics, Exoplanet, Radial velocity, Stars, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Noise (radio), Astrophysics - Earth and Planetary Astrophysics
Abstract

NEID is a high-resolution optical spectrograph on the WIYN 3.5-m telescope at Kitt Peak National Observatory and will soon join the new generation of extreme precision radial velocity instruments in operation around the world. We plan to use the instrument to conduct the NEID Earth Twin Survey (NETS) over the course of the next 5 years, collecting hundreds of observations of some of the nearest and brightest stars in an effort to probe the regime of Earth-mass exoplanets. Even if we take advantage of the extreme instrumental precision conferred by NEID, it will remain difficult to disentangle the weak (~10 cm s$^{-1}$) signals induced by such low-mass, long-period exoplanets from stellar noise for all but the quietest host stars. In this work, we present a set of quantitative selection metrics which we use to identify an initial NETS target list consisting of stars conducive to the detection of exoplanets in the regime of interest. We also outline a set of observing strategies with which we aim to mitigate uncertainty contributions from intrinsic stellar variability and other sources of noise., 19 pages, 10 figures, 1 table

Published
2021

39. An eccentric Brown Dwarf eclipsing an M dwarf

Author

Caleb I. Cañas, Suvrath Mahadevan, Chad F. Bender, Noah Isaac Salazar Rivera, Andrew Monson, Corey Beard, Jack Lubin, Paul Robertson, Arvind F. Gupta, William D. Cochran, Connor Fredrick, Fred Hearty, Sinclaire Jones, Shubham Kanodia, Andrea S. J. Lin, Joe P. Ninan, Lawrence W. Ramsey, Christian Schwab, and Guđmundur Stefánsson

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics::Solar and Stellar Astrophysics, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Galaxy Astrophysics, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the discovery of a $M=67\pm2~\mathrm{M_J}$ brown dwarf transiting the early M dwarf TOI-2119 on an eccentric orbit ($e=0.3362 \pm 0.0005$) at an orbital period of $7.200861 \pm 0.000005$ days. We confirm the brown dwarf nature of the transiting companion using a combination of ground-based and space-based photometry and high-precision velocimetry from the Habitable-zone Planet Finder. Detection of the secondary eclipse with TESS photometry enables a precise determination of the eccentricity and reveals the brown dwarf has a brightness temperature of $2100\pm80$ K, a value which is consistent with an early L dwarf. TOI-2119 is one of the most eccentric known brown dwarfs with $P, 31 pages, 8 figures, 3 tables, published in AJ, minor revisions to match published version

Published
2021
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40. A Mini-Neptune and a Radius Valley Planet Orbiting the Nearby M2 Dwarf TOI-1266 in Its Venus Zone: Validation with the Habitable-zone Planet Finder

Author

Arpita Roy, Chad F. Bender, Joe P. Ninan, Marissa Maney, Jason T. Wright, Caleb I. Cañas, Arvind F. Gupta, Andrew J. Metcalf, Connor Fredrick, William D. Cochran, Eric B. Ford, Andrew J. Monson, Paul Robertson, Samuel Halverson, Lawrence W. Ramsey, Mark E. Everett, Christian Schwab, Scott A. Diddams, Eric Levi, John P. Wisniewski, Ryan Terrien, Fred Hearty, G. Stefansson, Suvrath Mahadevan, Ravi Kumar Kopparapu, Andrea S. J. Lin, Michael Endl, Shubham Kanodia, and Leslie Hebb

Subjects
Physics, biology, Astronomy and Astrophysics, Venus, Radius, Astrophysics::Cosmology and Extragalactic Astrophysics, biology.organism_classification, Exoplanet, Astrobiology, Space and Planetary Science, Planet, Mini-Neptune, Astrophysics::Earth and Planetary Astrophysics, Circumstellar habitable zone, Astrophysics::Galaxy Astrophysics
Abstract

We report on the validation of two planets orbiting the nearby (36 pc) M2 dwarf TOI-1266 observed by the TESS mission. This system is one of a few M dwarf multiplanet systems with close-in planets where the inner planet is substantially larger than the outer planet. The inner planet is sub-Neptune-sized (R = 2.46 ± 0.08 R_⊕) with an orbital period of 10.9 days, while the outer planet has a radius of 1.67_(-0.11)^(+0.09) R_⊕ and resides in the exoplanet radius valley—the transition region between rocky and gaseous planets. With an orbital period of 18.8 days, the outer planet receives an insolation flux of 2.4 times that of Earth, similar to the insolation of Venus. Using precision near-infrared radial velocities with the Habitable-zone Planet Finder Spectrograph, we place upper mass limits of 15.9 and 6.4 M_⊕ at 95% confidence for the inner and outer planet, respectively. A more precise mass constraint of both planets, achievable with current radial velocity instruments given the host star brightness (V = 12.9, J = 9.7), will yield further insights into the dominant processes sculpting the exoplanet radius valley.

Published
2020

41. A warm Jupiter transiting an M dwarf: A TESS single transit event confirmed with the Habitable-zone Planet Finder

Author

Mark E. Everett, Samuel Halverson, Jayadev Rajagopal, Robert F. Wilson, Gudmundur Stefansson, Fred Hearty, Arpita Roy, Hannah M. Lewis, Arvind F. Gupta, Rebekah I. Dawson, Andrew J. Monson, William D. Cochran, Jason T. Wright, Christian Schwab, Mary Brewer, Scott A. Diddams, Ryan Terrien, Lawrence W. Ramsey, Suvrath Mahadevan, Connor Fredrick, Andrew J. Metcalf, Chad F. Bender, Andrea S. J. Lin, Eric B. Ford, Paul Robertson, Caleb I. Cañas, Corey Beard, Leslie Hebb, Steven R. Majewski, Joe P. Ninan, Shubham Kanodia, Michael Endl, and Jack Lubin

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, 010504 meteorology & atmospheric sciences, Gas giant, FOS: Physical sciences, Astronomy, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, Exoplanet, Photometry (optics), Orbit, Astrophysics - Solar and Stellar Astrophysics, 13. Climate action, Space and Planetary Science, Planet, 0103 physical sciences, Astrophysics::Earth and Planetary Astrophysics, 010303 astronomy & astrophysics, Circumstellar habitable zone, Solar and Stellar Astrophysics (astro-ph.SR), Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, Astrophysics - Earth and Planetary Astrophysics
Abstract

We confirm the planetary nature of a warm Jupiter transiting the early M dwarf TOI-1899, using a combination of available TESS photometry; high-precision, near-infrared spectroscopy with the Habitable-zone Planet Finder; and speckle and adaptive optics imaging. The data reveal a transiting companion on an $\sim29$-day orbit with a mass and radius of $0.66\pm0.07\ \mathrm{M_{J}}$ and $1.15_{-0.05}^{+0.04}\ \mathrm{R_{J}}$, respectively. The star TOI-1899 is the lowest-mass star known to host a transiting warm Jupiter, and we discuss the follow-up opportunities afforded by a warm ($\mathrm{T_{eq}}\sim362$ K) gas giant orbiting an M0 star. Our observations reveal that TOI-1899.01 is a puffy warm Jupiter, and we suggest additional transit observations to both refine the orbit and constrain the true dilution observed in TESS., 24 pages, 5 figures, 3 tables, published in AJ

Published
2020

42. The TESS-Keck Survey. I. A Warm Sub-Saturn-mass Planet and a Caution about Stray Light in TESS Cameras

Author

M. F. Andersen, Jeffrey C. Smith, Lauren M. Weiss, Enric Palle, Andrew W. Mayo, Teo Mocnik, Robert F. Goeke, David W. Latham, Ashley Chontos, Aida Behmard, Sara Seager, Howard Isaacson, Courtney D. Dressing, Daryll LaCourse, Judah Van Zandt, Joshua E. Schlieder, Monika Lendl, Chelsea X. Huang, Steven Giacalone, Paul A. Dalba, Joshua N. Winn, Erik A. Petigura, Joseph E. Rodriguez, Douglas A. Caldwell, Corey Beard, Roland Vanderspek, Stephen R. Kane, Lea A. Hirsch, Steven Villanueva, Martti H. Kristiansen, Nicholas Scarsdale, Emil Knudstrup, William Fong, Lee J. Rosenthal, Andrew Vanderburg, Paul Robertson, Ryan A. Rubenzahl, Samuel N. Quinn, Michelle L. Hill, George R. Ricker, Diana Dragomir, Molly R. Kosiarek, Arpita Roy, Tansu Daylan, Ian J. M. Crossfield, David R. Ciardi, Pamela Rowden, Natalie M. Batalha, Mark E. Rose, Allyson Bieryla, Gilbert A. Esquerdo, Keivan G. Stassun, Daniel J. Stevens, Jack Lubin, Joshua Pepper, Andrew W. Howard, Jon M. Jenkins, Benjamin J. Fulton, Arvind F. Gupta, H. P. Osborn, Tom Jacobs, Joseph M. Akana Murphy, Xinyu Yao, Daniel Huber, Frank Grundahl, and Ryan Cloutier

Subjects
Dwarf star, Radial velocity, 010504 meteorology & atmospheric sciences, Exoplanet astronomy, FOS: Physical sciences, 01 natural sciences, METHANE, Planet, 0103 physical sciences, Exoplanet detection methods, Direct imaging, Transit (astronomy), 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), Spectroscopy, 0105 earth and related environmental sciences, Physics, JUPITER, Earth and Planetary Astrophysics (astro-ph.EP), ERROR-CORRECTION, Exoplanets, Astronomy, Astronomy and Astrophysics, Surface gravity, Light curve, Orbital period, Exoplanet, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, F dwarf stars, STATISTICAL PROPERTIES, Transit photometry, Astrophysics - Instrumentation and Methods for Astrophysics, STARS, Astrophysics - Earth and Planetary Astrophysics
Abstract

We report the detection of a Saturn-size exoplanet orbiting HD 332231 (TOI 1456) in light curves from the Transiting Exoplanet Survey Satellite (TESS). HD 332231, an F8 dwarf star with a V-band magnitude of 8.56, was observed by TESS in Sectors 14 and 15. We detect a single-transit event in the Sector 15 presearch data conditioning (PDC) light curve. We obtain spectroscopic follow-up observations of HD 332231 with the Automated Planet Finder, Keck I, and SONG telescopes. The orbital period we infer from the radial velocity (RV) observations leads to the discovery of another transit in Sector 14 that was masked by PDC due to scattered light contamination. A joint analysis of the transit and RV data confirms the planetary nature of HD 332231 b, a Saturn-size ($0.867^{+0.027}_{-0.025} \; R_{\rm J}$), sub-Saturn-mass ($0.244\pm0.021 \; M_{\rm J}$) exoplanet on a 18.71 day circular orbit. The low surface gravity of HD 332231 b and the relatively low stellar flux it receives make it a compelling target for transmission spectroscopy. Also, the stellar obliquity is likely measurable via the Rossiter-McLaughlin effect, an exciting prospect given the 0.14 au orbital separation of HD 332231 b. The spectroscopic observations do not provide substantial evidence for any additional planets in the HD 332231 system, but continued RV monitoring is needed to further characterize this system. We also predict that the frequency and duration of masked data in the PDC light curves for TESS Sectors 14-16 could hide transits of some exoplanets with orbital periods between 10.5 and 17.5 days., Comment: 17 pages, 9 figures, 4 tables. Published in the Astronomical Journal

Published
2020

43. Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

Author

Cullen H. Blake, Jason T. Wright, Paul Robertson, Gudmundur Stefansson, Shubham Kanodia, Chad F. Bender, Eli Golub, Joe P. Ninan, Marsha J. Wolf, Kurt P. Jaehnig, Suvrath Mahadevan, Arpita Roy, Jayadev Rajagopal, Ryan Terrien, Kyle Kaplan, Sarah E. Logsdon, Christian Schwab, Michael W. McElwain, Andrew J. Monson, Sharon X. Wang, Arvind F. Gupta, and Samuel Halverson

Subjects
010504 meteorology & atmospheric sciences, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, 01 natural sciences, law.invention, Telescope, Sky brightness, law, 0103 physical sciences, 010303 astronomy & astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), 0105 earth and related environmental sciences, Remote sensing, Physics, Earth and Planetary Astrophysics (astro-ph.EP), Observational error, Spectrometer, Diffuse sky radiation, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, Exoplanet, Radial velocity, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Circumstellar habitable zone, Astrophysics - Earth and Planetary Astrophysics
Abstract

Solar contamination, due to moonlight and atmospheric scattering of sunlight, can cause systematic errors in stellar radial velocity (RV) measurements that significantly detract from the ~10 cm s−1 sensitivity required for the detection and characterization of terrestrial exoplanets in or near habitable zones of Sun-like stars. The addition of low-level spectral contamination at variable effective velocity offsets introduces systematic noise when measuring velocities using classical mask-based or template-based cross-correlation techniques. Here we present simulations estimating the range of RV measurement error induced by uncorrected scattered sunlight contamination. We explore potential correction techniques, using both simultaneous spectrometer sky fibers and broadband imaging via coherent fiber imaging bundles, that could reliably reduce this source of error to below the photon-noise limit of typical stellar observations. We discuss the limitations of these simulations, the underlying assumptions, and mitigation mechanisms. We also present and discuss the components designed and built into the NEID (NN-EXPLORE Exoplanet Investigations with Doppler spectroscopy) precision RV instrument for the WIYN 3.5 m telescope, to serve as an ongoing resource for the community to explore and evaluate correction techniques. We emphasize that while "bright time" has been traditionally adequate for RV science, the goal of 10 cm s−1 precision on the most interesting exoplanetary systems may necessitate access to darker skies for these next-generation instruments.

Published
2020

44. Surgical site infection after gastrointestinal surgery in children: An international, multicentre, prospective cohort study

Author

Harrison, E.M. Drake, T.M. Ghosh, D. Ademuyiwa, A.O. Bhangu, A. Fitzgerald, J.E. Glasbey, J. Borda-Luque, G. Costas-Chavarri, A. Ntirenganya, F. Fergusson, S.J. Ingabire, J.C.A. Ismaïl, L. Lilford, R. Mihaljevic, A.L. Morton, D. Mutabazi, A.Z. Adisa, A.O. Ots, R. Pinkney, T. Poškus, T. Shaw, C.A. Verjee, A. Runigamugabo, E. Khatri, C. Mohan, M. Jaffry, Z. Altamini, A. Kirby, A. Soreide, K. Cornick, J. Iyer, D. King, S. Arthur, T. Nahar, S.N. Waterman, A. Lawini, I. Rouse, T. Correa, J.C. Salem, H.K. Worku, M. Arnaud, A. Kalles, V. Aguilera, M.L. Recinos, G. Quek, R. Altibi, A. Whitaker, J. Bent, Z. Al-Slaibi, I. Tahboub, H. Alser, O.H. Shu, S. Mironescu, A. Bratu, M. Altwijri, A. Alsaggaf, M.U. Jubran, A.F. Seisay, S. Jeyakumar, J. Senanayake, K. Abdulbagi, O. Raptis, D. Kong, C. Suresh, S. Scott, M. Grizhja, B. Ymeri, S. Galiqi, G. Klappenbach, R. Antezana, D. Beleño, A.E.M. Costa, C. Sanchez, B. Aviles, S. Modolo, M.M. Fermani, C.G. Balmaceda, R. Villalobos, S. Carmona, J.M. Hamill, D. Deutschmann, P. Sandler, S. Cox, D. Nataraja, R. Sharpin, C. Ljuhar, D. Gray, D. Haines, M. Iyer, D. Niranjan, N. D'Amours, S. Ashtari, M. Franco, H. Mitul, A.R. Karim, S. Aman, N.F. Estee, M.M. Salma, U. Razzaque, J. Hamidkanta, T. Tori, S. Alamin, Md.S. Roy, S. Al Amin, Md.S. Haque, M. Faruq, A. Iftekhar, F. O'Shea, M. Padmore, G. Jonnalagadda, R. Litvin, A. Filatau, A. Paulouski, D. Shubianok, M. Shachykava, T. Khokha, D. Khokha, V. Djivoh, F. Lawani, I. Dossou, F. Seto, D.M. Gbessi, D.G. Noukpozounkou, B. Souaibou, Y.I. Keke, K.R. Hodonou, F. Ahounou, E. Alihonou, T. Dénakpo, M. Ahlonsou, G. Bedada, A.G. Nsengiyumva, C. Kwizera, S. Barendegere, V. Choi, P. Stock, S. Jamal, L. Firdouse, M. Zani, A. Azzie, G. Kushwaha, S. Agarwal, A. Chen, T.-L. Yip, C. Montes, I. Zapata, F. Sierra, S. Lanau, M.I.V. Arango, M.C.M. Restrepo, I.M. Sierra, S. Giraldo, R.S.R. Mendozaarango, M. Domini, E. Karlo, R. Mihanovic, J. Youssef, M. Elfeki, H. Thabet, W. Sanad, A. Tawfik, G. Zaki, A. Abdel-Hameed, N. Mostafa, M. Omar, M.F.W. Ghanem, A. Abdallah, E. Denewer, A. Emara, E. Rashad, E. Sakr, A. Elashry, R. Emile, S. Khafagy, T. Elhamouly, S. Elfarargy, A. Mamdouhmohamed, A. Saiednagy, G. Esam, A. Elwy, E. Hammad, A. Khallaf, S. Ibrahim, E. Saidbadr, A. Moustafa, A. Eldosoukymohammed, A. Elgheriany, M. Abdelmageed, E. Al Raouf, E.A. Elbanby, E. Elmasry, M. Morsyfarahat, M. Yahyamansor, E. Magdyhegazy, E. Gamal, E. Gamal, H. Kandil, H. Maherabdelrouf, D. Moaty, M. Gamal, D. El-Sagheer, N. Salah, M. Magdy, S. Salah, A. Essam, A. Ali, A. Badawy, M. Ahmed, S. Mohamed, M. Assal, A. Sleem, M. Ebidy, M. Abdelrazek, A. Zahran, D. Adam, N. Nazir, M. Hassanein, A.B. Ismail, A. Elsawy, A. Mamdouh, R. Mabrouk, M. Ahmed, L.A.M. Hassabalnaby, M. Magdy, E. Abd-Elmawla, M. Fahim, M. Mowafy, B. Mahmoud, M.I. Allam, M. Alkelani, M. El Gendy, N.H. Aboul-Naga, M.S. Alaael-Din, R. Elgendy, A.H. Ismail, M. Shalaby, M. Elsharkawy, A.A. Moghazy, M.E. Elbisomy, K.H. Shakshouk, H.A.G. Hamed, M.F. Ebidy, M.M. Abdelkader, M. Karkeet, M. Ahmed, H. Adel, I. Omar, M.E. Ibrahim, M. Ghoneim, O. Hesham, O. Gamal, S. Hilal, K. Arafa, O. Awad, S.A. Salem, M. Elsherif, F.A. Elsabbagh, N. Aboelsoud, M.R. Rida, A.H.E.F. Hossameldin, A. Hany, E. Asar, Y.H. Anwar, N. Gadelkarim, M. Abdelhady, S. Morshedy, E.M. Saad, R. Soliman, N. Salama, M. Ezzat, E. Mohamed, A. Ibrahim, A. Fergany, A. Mohammed, S. Reda, A. Allam, Y. Saad, H.A. Abdelfatah, A. Fathy, A.M. El-Sehily, A. Kasem, E.A. Hassan, A.T.A. Mohammed, A.R. Saad, A.G. Elfouly, Y. Elfouly, N. Ibrahim, A. Hassaan, A. Mohammed, M.M. Elhoseny, G. Magdy, M. Elkhalek, E.A. Zakaria, Y. Ezzat, T. El Dahab, A.A. Kelany, M. Arafa, S. Hassan, O.M.M. Badwi, N.M. Sleem, A.S. Ahmed, H. Abdelbadeai, K. Abdullah, M.A. Lokman, M. Bahar, S. Radyabdelazeam, A. Adelshone, A. Hasnan, M.B. Zulkifli, A. Kamarulzamil, S.N.A. Elhendawy, A. Latif, A. Adnan, A.B. Shaharuddin, S. Majid, A.H.H.A. Amreia, M. Al-Marakby, D. Salma, M. Ismail, M. Basir, E.R.M. Ali, C.D.M. Ata, A.Y. Nasr, M. Rezq, A. Sheta, A. Tariq, S. Sallam, A. Darwish, A.K.Z. Elmihy, S. El Hadry, S. Farag, A. Hajah, H. Seliem, A. Aglan, A. Zohair, A. Essam, M. Moussa, O. El-Gizawy, E. Samy, M. Ali, S. Elhalawany, E. Ata, A. Elhalawany, M. Nashat, M. Soliman, S. Elazab, A. Samy, M. Abdelaziz, M.A. Ibrahim, K. Ibrahim, A.M. Gado, A. Hantour, U. Eldeen, E.A. Loaloa, M.R. Abouzaid, A. Ahmedbahaaeldin, M. Hashad, E. Sroor, F. Gamil, D. Mahmoudabdulhakeem, E. Zakaria, M. Mohamed, F. Abubakr, M. Ali, E. Magdy, H. Ramadan, M. Abdelatymohamed, M. Mansour, S. Abdulazizamin, H. Rabiemohamed, A. Saami, M. Ahmedredaelsayed, N. Tarek, A. Mohyeldeenmahmoud, S. El Sayed, I.M. Reda, A. Yusufshawky, M. Mousasalem, M. El-Din, S.A. Soliman, N.A. Talaat, M. Abdelmoenelhusseiny, S.A.-D.A. Abdullah, N. Ahmedbahaaeldin, M. Elshaar, M. Abdelfatahibraheem, A. Abdulaziz, H. Ismail, M.K. Hamdymadkor, M. Abdelaty, M. Kader, S.M. Mohamedsalah, O. Eldafrawy, M. Zakieldeeb, A. Mahmoudeid, M. Attia, A. El-Dien, K.S. Shwky, A. Badenjki, M.A. Soliman, A. Al Attar, S.M. Sayed, F. Abdelsabour, F. Azizeldine, M.G. Shawqi, M. Hashim, A. Aamer, A. Raouf, A.M.A. Abdelshakour, M. Ibrahim, A. Mahmoud, B. Mahmoud, M.A. Qenawy, M. Rashed, A.M. Dahy, A. Sayed, M. Shamsedine, A.W. Mohamed, B. Hasan, A. Saad, M.M. Abdulbassit, K. Khalidabdelatif, N. Elzahed, N. Elkashash, A. Bekhet, N.M. Hafez, S. Gad, A. Maher, M.E. Abdelsameea, A. Hafez, M. Sabe, A. Ahmed, A. Shahine, A. Dawood, K. Gaafar, S. Husseiny, R. Aboelmagd, O. Soliman, A. Mesbah, N. Emadeldin, H. Almeligy, A. Bekhet, A.H. Hasan, D. Alhady, K. Sabe, A.K. Elnajjar, M.A. Aboelella, M. Hamsho, W. Hassan, I. Saad, H. Abdelazim, G. Mahmoud, H. Wael, N. Kandil, A.M. Magdy, A. Saidelkholy, S. Adel, B. Dabbour, K. Elsherbiney, S. Mattar, O. Abdrabou, A.K. Aly, M.Y.M. Geuoshy, A. Elnagar, A. Ahmed, S. Abdelmotaleb, I. Saleh, A.A. Mohammedbakry, H. Saeed, M. Mahmoud, S. Tawfik, B. Ismail, S.A. Zakaria, E. Gad, M.O. Elhelbawy, M. Bassem, M. Khaledabdel-Latif, N. Maraie, N. Elhadary, N.M. Semeda, N. Rabiemohamed, S. Bakry, H.M. Essam, A.A. Tarek, D. Ashour, K. Elhadad, A. Abdel-Aty, A. Rakha, I. Matter, S.M. Abdelhamed, R. Abdelkader, O. Hassaan, A. Soliman, Y. Mohamed, A. Ghanem, S. Farouk, S.A.M. Ibrahim, E.M. El-Taher, E. Mostafa, M. Mahrousbadr, M. El-Sawy, R.E.A. Bakr, A. Al Rafati, A.A.R. Saar, S. Reinsoo, A. Talving, P. Seyoum, N. Worku, T. Fitsum, A. Tolonen, M. Leppaniemi, A. Sallinen, V. Parmentier, B. Peycelon, M. Irtan, S. Dardenne, S. Robert, E. Maillot, B. Courboin, E. Arnaud, A.P. Hascoet, J. Abbo, O. Kaci, A.A. Prudhomme, T. Ballouhey, Q. Grosos, C. Fourcade, L. Cecilia, T. Jean-Francois, C. Helene, F.-C. Delforge, X. Haraux, E. Dousset, B. Schiavone, R. Gaujoux, S. Marret, J.-B. Haffreingue, A. Rod, J. Renaux-Petel, M. Lecompte, J.-F. Breaud, J. Gastaldi, P. Taieb, C. Claire, R. Anis, E. Bustangi, N. Lopez, M. Scalabre, A. Grella, M.G. Mariani, A. Podevin, G. Schmitt, F. Hervieux, E. Broch, A. Muller, C. Tabiri, S. Kojo, A.T.T. Bandoh, D. Abantanga, F. Kyereh, M. Asumah, H. Appiah, E.K. Wondoh, P. Gyedu, A. Dally, C. Amoah, K.A.M. Yifieyeh, A. Agbedinu, K. Owusu, F. Amoako-Boateng, M. Dayie, M. Hagan, R. Debrah, S. Ohene-Yeboah, M. Clegg-Lampety, J.-N. Etwire, V. Dakubo, J. Essoun, S. Bonney, W. Glover-Addy, H. Osei-Nketiah, S. Amoako, J. Adu-Aryee, N. Appeadu-Mensah, W. Bediako-Bowan, A. Dedey, F. Ekow, M. Akatibo, E. Yakubu, M. Kordorwu, H.E.K. Asare-Bediako, K. Tackie, E. Aaniana, K. Acquah, E. Opoku-Agyeman, R. Avoka, A. Kusi, K. Maison, K. Gyamfi, F.E. Naabarnabas, G. Abdul-Latif, S. Taahamoako, P. Davor, A. Dassah, V. Dagoe, E. Kwakyeafriyie, P. Akoto, E. Ackom, E. Mensah, E. Atkins, E.T. Coompson, C.L. Ivros, N. Ferousis, C. Kalles, V. Agalianos, C. Kyriazanos, I. Barkolias, C. Tselos, A. Tzikos, G. Voulgaris, E. Lytras, D. Bamicha, A. Psarianos, K. Stefanopoulos, A. Patoulias, I. Sfougaris, D. Valioulis, I. Balalis, D. Korkolis, D. Manatakis, D.K. Kyrou, G. Karabelias, G. Papaskarlatos, I.-A. Konstantina, K. Zampitis, N. Germanos, S. Papailia, A. Theodosopoulos, T. Gkiokas, G. Mitroudi, M. Panteli, C. Feidantsis, T. Farmakis, K. Kyziridis, D. Ioannidis, O. Parpoudi, S. Gemenetzis, G. Parasyris, S. Anthoulakis, C. Nikoloudis, N. Margaritis, M. Aguilera-Arevalo, M.-L. Coyoy-Gaitan, O. Rosales, J. Tale, L. Soley, R. Barrios, E. Rodriguez, S.T.T. Pazgalvez, C. Herreracruz, D. Rosenberg, G.S. Matheu, A. Cohen, D.M. Paul, M. Charles, A. Lam, J.C.Y. Yeung, M.H.A. Fok, C.Y.J. Li, K.H.G. Lai, A.C.-H. Cheung, Y.H.E. Wong, H.Y. Leung, K.W. Lee, T.S.B. Lam, W.H. Dao, W. Kwok, S.H.-W. Chan, T.-Y.K. Ng, Y.K. Liu, Q. Foo, C.C. Yang, J. Kumar, B. Bhatnagar, A. Upadhyaya, V. Kumar, S. Muddebihal, U. Dar, W. Kc, J. Alexander, P. Aruldas, N. Adella, F.J. Rulie, A.S. Iskandar, F. Setiawan, J. Evajelista, C.V. Natalie, H. Arlindawati Gunawan, R. Karismaningtyas, H. Mata, L. Andika, F. Hasanah, A. Widiastini, T.A. Purwaningsih, N. Mukin, A.D.F. Rahmah, D. Nurqistan, H. Arsyad, H. Adhitama, N. Jeo, W. Sutandi, N. Clarissa, A. Gultom, P.A. Billy, M. Haloho, A. Amandito, R. Johanna, N. Lee, F. Dorani, R.M.N.R. Glynn, M. Alherz, M. Goh, W. Shiwani, H.A. Sproule, L. Conlon, K.C. Bala, M. Kedar, A. Turati, L. Bianco, F. Steccanella, F. Gallo, G. Trompetto, M. Clerico, G. Papandrea, M. Sammarco, G. Sacco, R. Benevento, A. Pata, F. Giavarini, L. Giglio, M.C. Bucci, L. Pagano, G. Sollazzo, V. Peltrini, R. Luglio, G. Birindelli, A. Di Saverio, S. Tugnoli, G. Paludi, M.A. Mingrone, P. Pata, D. Selvaggi, F. Selvaggi, L. Pellino, G. Di Martino, N. Curletti, G. Aonzo, P. Galleano, R. Berti, S. Francone, E. Boni, S. Lorenzon, L. Lo Conte, A. Balducci, G. Confalonieri, G. Pesenti, G. Gavagna, L. Vasquez, G. Targa, S. Occhionorelli, S. Andreotti, D. Pata, G. Aquilino, F. Chetta, N. Picciariello, A. Abdelkhalek, M. Belli, A. de Franciscis, S. Bigaran, A. Favero, A. Basso, S.M.M. Salusso, P. Perino, M. Mochet, S. Sasia, D. Riente, F. Migliore, M. Merlini, D. Basilicò, S. Corbellini, C. Lazzari, V. Macchitella, Y. Bonavina, L. Angelieri, D. Coletta, D. Falaschi, F. Catani, M. Reali, C. Malavenda, M. Del Basso, C. Ribaldi, S. Coletti, M. Natili, A. Depalma, N. Iannone, I. Antoniozzi, A. Rossi, D. Gui, D. Perrotta, G. Ripa, M. Giardino, F.R. Foco, M. Vicario, E. Coccolini, F. Ansaloni, L. Nita, G.E. Leone, N. Bondurri, A. Maffioli, A. Simioni, A. de Boni, D. Pasquali, S. Goldin, E. Vendramin, E. Ciccioli, E. Tedeschi, U. Bortolasi, L. Violi, P. Campagnaro, T. Conci, S. Lazzari, G. Iacono, C. Guglielmi, A. Manfreda, S. Rinaldi, A. Ringressi, M.N. Brunoni, B. Salamone, G. Mangiapane, M. de Marco, P. la Brocca, A. Tutino, R. Silvestri, V. Licari, L. Fontana, T. Cocorullo, N.F.G. Shalaby, M. Sileri, P. Arcudi, C. Bsisu, I. Aljboor, K. Abusalem, L. Alnusairat, A. Qaissieh, A. Al-Dakka, E. Ababneh, A. Halhouli, O. Yusufali, T. Mohammed, H. Lando, J. Parker, R. Ndegwa, W. Jokubauskas, M. Gribauskaite, J. Venskutonis, D. Kuliavas, J. Dulskas, A. Samalavicius, N.E. Jasaitis, K. Parseliunas, A. Nevieraite, V. Montrimaite, M. Slapelyte, E. Dainius, E. Riauka, R. Subocius, Z.D.A. Venclauskas, L. Gulbinas, A. Bradulskis, S. Kasputyte, S. Mikuckyte, D. Kiudelis, M. Zilinskas, J. Jankus, T. Petrikenas, S. Pazusis, M. Urniezius, Z. Vilcinskas, M. Banaitis, V.J. Gaizauskas, V. Grisin, E. Mazrimas, P. Rackauskas, R. Drungilas, M. Lagunavicius, K. Lipnickas, V. Majauskyte, D. Jotautas, V. Abaliksta, T. Uscinas, L. Simutis, G. Ladukas, A. Danys, D. Laugzemys, E. Mikalauskas, S. Poskus, T. Sruogiene, E.Z. Visinskas, P. Zilinskiene, R. Dragatas, D. Burmistrovas, A. Tverskis, Z. Vaicius, A. Mazelyte, R. Zadoroznas, A. Kaselis, N. Ziubrytė, G. Rahantasoa, F.C.F.P. Samison, L.H. Rasoaherinomenjanahary, F. Tolotra, T.E.C. Mukuzunga, C. Msosa, V. Kwatiwani, C. Msiska, N. Chai, F.Y. Asilah, S.M.D. Syibrah, K.Z. Chin, P.X. Salleh, A. Riswan, N.Z. Roslani, A.C. Chong, H.-Y. Aziz, N.A. Poh, K.-S. Chai, C.-A. Kumar, S. Taher, M.M. Kosai, N.R. Aziz, D.N.A. Rajan, R. Julaihi, R. Jethwani, D.L. Yahaya, M.T. Abdullah, N.A.N. Mathew, S.W. Chung, K.J. Nirumal, M.K. Tze, R.G.E. Ali, S.A.W.E.W. Gan, Y.Y. Ting, J.R.S. Sii, S.S.Y. Koay, K.L. Tan, Y.K. Cheah, A.E.Z. Wong, C.Y. Mat, T.N.T. Chow, C.Y.N. Har, P.A.L. Der, Y. Tew, Y.Y. Henry, F. Low, X. Neo, Y.T. Heng, H.E. Kong, S.N. Gan, C. Mok, Y.T. Tan, Y.W. Palayan, K. Devatata, M. Cheong, Y.J. Gunaseelan, K. Nasir, W.N.A.W.M. Yoganathan, P. Lee, E.X. Saw, J.E. Yeang, L.J. Koh, P.Y. Lim, S.Y. Teo, S.Y. Grech, N. Magri, D. Cassar, K. Mizzi, C. Falzon, M. Shaikh, N. Scicluna, R. Zammit, S. Borg, E. Mizzi, S. Brincat, S.D. Tembo, T. Le, V.T.H. Grima, T. Sammut, K. Carabott, K. Farrugia, A. Zarb, C. Navarro, A. Dimech, T. Camilleri, G. Bertuello, I. Dalli, J. Bonavia, K. Corro-Diaz, S. Manriquez-Reyes, M. Ramos-De la Medina, A. Abdelhamid, A. Hrora, A. Benammi, S. Bachri, H. Abbouch, M. Boukhal, K. Bennai, R.M. Belkouchi, A. Jabal, M.S. Benyaiche, C. Vermaas, M. Duinhouwer, L. Pastora, J. Wood, G. Merlo, M.S. Ajao, A. Ayandipo, O. Lawal, T. Abdurrazzaaq, A. Habeeb, O. Alada, M. Nasir, A. Adeniran, J. Habeeb, O. Popoola, A. Adeyeye, A. Adebanjo, A. Adesanya, O. Adeniyi, A. Mendel, H. Bello, B. Muktar, U. Osinowo, A. Olajide, T.O. Oshati, O. Ihediwa, G. Adenekan, B. Nwinee, V. Alakaloko, F. Ademuyiwa, A. Elebute, O. Lawal, A. Bode, C. Olugbemi, M. Adesina, A. Faturoti, O. Odutola, O. Adebola, O. Onuoha, C. Taiwo, O. Williams, O. Balogun, F. Ajai, O. Oludara, M. Njokanma, I. Osuoji, R. Kache, S. Ajah, J. Makama, J. Adamu, A. Baba, S. Aliyu, M. Aliyu, S. Ukwenya, Y. Aliyu, H. Sholadoye, T. Daniyan, M. Ogunsua, O. Anyanwu, L.-J. Sheshe, A. Mohammad, A. Olori, S.D. Mshelbwala, P. Odeyemi, B. Samson, G. Timothy, O.K. Samuel, S.A. Ajiboye, A. Adeyeye, A. Amole, I. Abiola, O. Olaolorun, A. Søreide, K. Veen, T. Kanani, A. Styles, K. Herikstad, R. Larsen, J.W. Søreide, J.A. Jensen, E. Gran, M. Aahlin, E.K. Gaarder, T. Monrad-Hansen, P.W. Næss, P.A. Lauzikas, G. Wiborg, J. Holte, S. Augestad, K. Banipal, G. Banipal, G. Monteleone, M. Moe, T. Schultz, J. Al-Taher, T. Hamdan, A. Salman, A. Saadeh, R. Musleh, A. Jaradat, D. Abushamleh, S. Hanoun, S. Qumbos, A.A. Hamarshi, A. Taher, A.A. Qawasmi, I. Qurie, K. Altarayra, M. Ghannam, M. Shaheen, A. Herebat, A. Abdelhaq, A. Shalabi, A. Abu-Toyour, M. Asi, F. Shamasneh, A. Atiyeh, A. Mustafa, M. Zaatreh, R. Dabboor, M. Alaloul, E. Baraka, H. Meqbil, J. Al-Buhaisi, A. Elshami, M. Afana, S. Jaber, S. Alyacoubi, S. Abuowda, Y. Idress, T. Abuqwaider, E. Al-Saqqa, S.W. Bowabsak, A. Eljamassi, A. Hasanain, D. Al-Farram, H. Salah, M. Firwana, A. Hamdan, M. Awad, I. Ashour, A. Al Barrawi, F.E. Al-Khatib, A. Al-Faqawi, M. Fares, M. Elmashala, A. Adawi, M. Adawi, I. Khreishi, R. Khreishi, R. Ashour, A. Ghaben, A. Nadeem, N. Saqlain, M. Abbasy, J. Alvi, A.R. Gala, T. Shahzad, N. Bhopal, K.F. Iftikhar, Z. Butt, M.T. Ul Razi, S.A. Ahmed, A. Niazi, A.K. Raza, I. Baluch, F. Raza, A. Bani-Sadar, A. Qureshi, A.U. Adil, M. Raza, A. Javaid, M. Waqar, M. Khan, M. Arshad, M. Amjad, M. Vega, G.M.M. Cardozo, J.T. Roche, M.O. Servin, G.R.P. Lohse, H.A.S. Lopez, L.I.P. Cardozo, R.A.M. Espinoza, F. Rojas, A.D.P. Sanchez, D. Samaniego, C.S. Torres, S.G. Calua, A.C. Razuri, C. Ortiz, N. Rodriguez, X. Carrasco, N. Saravia, F. Miyasato, H.S. Valcarcel-Saldana, M. Bermudez, Y.E.A. Carpio, J. Ruizpanez, W. Toribioorbegozo, P. Duenas, C.G. Espinoza, K.T. Barrantes, A.M.S. Chungui, J. Shu, S. Fuentes-Rivera, L. Fernandez, C. Romani, D. Barbara Ye, J. Velasquez, R. Salcedo, J. Contreras-Vergara, A.L. Mejia, A.G.V. Montejo, M.S.G. Escalantesalas, M. Alccaticona, W. Vargas, M. Manriquesila, G. Mas, R. del Pilar Paucar, A. Velasquez, A.J.R. Robledo-Rabanal, A. Solis, L.A.Z. Espinoza, K.T. Hamaguchi, J.L.H. Farfan, E.S.F. Barrientos, L.A.M. Matta, J.J.H. Mora, J.J.V. Redota, M.A.P. Roxas, M.F. Mano, M.J.B. Parreno-Sacdalan, M.D. Lapitan, M.C. Almanon, C.L. Waledziak, M. Roszkowski, R. Janik, M. Lasek, A. Major, P. Radkowiak, D. Rubinkiewicz, M. Fernandes, C. Costa-Maia, J. Melo, R. Muntean, L. Mironescu, A.S. Vida, L.C. Kourdouli, A. Popa, M. Mircea, H. Vartic, M. Diaconescu, B. Bratu, M.R. Negoi, I. Beuran, M. Ciubotaru, C. Ingabire, J.C.A. Alphonse, M. Uzabumwana, N. Duhoranenayo, D. Jovine, E. Zanini, N. Landolfo, G. Aljiffry, M. Idris, F. Alghamdi, M.S.A. Maghrabi, A. Altaf, A. Khalifah, E. Gudal, A. Albiety, A. Alkaaki, A. Alshareef, R. Khoja, A. Nawawi, A. Najjar, M. Turkustani, S. Sahel, S. Alzahrani, A. Alghamdi, A. Alhazmi, W. Al Saied, G. Alamoudi, M. Riaz, M.M. Hassanain, M. Alhassan, B. Altamimi, A. Alyahya, R. Alsubaie, N. Albastawis, F. Altamimi, A. Nouh, T. Khan, R. Radojkovic, M. Jeremic, L. Nestorovic, M. Law, J.H. Tan, K.S.K. Tan, R.C.K. Tan, J.K. Joel, L.W.L. Lieske, B. Chan, X.W. Leong, F.Q.H. Chong, C.S. Koh, S. Lee, K.Y. Lee, K.C. Pluke, K. Dedekind, B. Nashidengo, P. Hampton, M.I. Joosten, J. Sobnach, S. Roodt, L. Sander, A. Pape, J. Spence, R. Maistry, N. Ndwambi, P. Kinandu, K. Tun, M. du Toit, F. Ellison, Q. Burger, S. Grobler, D.C. Khulu, L.B. Moore, R. Jennings, V. Leusink, A. Kariem, N. Gouws, J. Chu, K. Bougard, H. Noor, F. Dell, A. Rayne, S. van Straten, S. Khamajeet, A. Tshisola, S.K. Kabongo, K. Kong, V. Moodley, Y. Anderson, F. Madiba, T. du Plooy, F. Hartford, L. Chilton, G. Karjiker, P. Mabitsela, M. Ndlovu, S. Badicel, M. Jaich, R. Ruiz-Tovar, J. Garcia-Florez, L. Otero-Diez, J.L. Ramosperez, V. Aguadosuarez, N. Garcia, J.M. Moreno, S.C. Collado, M.V. Carneros, V.J. Septiem, J.G. Gonzalez, M. Picardo, A. Esteban, E. Ferrero, E. Ortega, I. Espin-Basany, E. Blanco-Colino, R. Andriola, V. Lorena, I. Contreras, E. Garcíabernardo, C. Pagnozzi, J. Sanz, S. Miyardeleon, A. Dorismé, A. Rodicio, J. Suarez, A. Stuva, J. Diazvico, T. Fernandez-Vega, L. Soldevila-Verdeguer, C. Sena-Ruiz, F. Pujol-Cano, N. Diaz-Jover, P. Garcia-Perez, J.M. Segura-Sampedro, J.J. Pineño-Flores, C. Ambrona-Zafra, D. Craus-Miguel, A. Jimenez-Morillas, P. Mazzella, A. Jayathilake, A.B. Thalgaspitiya, S.P.B. Wijayarathna, L.S. Wimalge, P.M.S.N. Sanni, H.A. Ndajiwo, A. Okenabirhie, O. Homeida, A. Younis, A. Omer, O.A. Abdulaziz, M. Mussad, A. Gilani, A.M. Cengiz, Y. Björklund, I. Ahlqvist, S. Ahlqvist, S. Thorell, A. Wogensen, F. Sokratous, A. Breistrand, M. Thorarinsdottir, H. Sigurdadottir, J. Nikberg, M. Chabok, A. Hjertberg, M. Elbe, P. Saraste, D. Rutkowski, W. Forlin, L. Niska, K. Sund, M. Oswald, D. Peros, G. Bluelle, R. Reinisch, K. Frey, D. Palma, A. Raptis, D. Zumbühl, L. Zuber, M. Schmid, R. Werder, G. Nocito, A. Gerosa, A. Mahanty, S. Widmer, L.W. Müller, J. Gübeli, A. Zuk, G. Gulcicek, O.B. Altinel, Y. Vartanoglu, T. Kose, E. Karahan, S.R. Aydin, M.C. Sahbaz, N.A. Halicioglu, I. Alis, H. Sapci, I. Adiyaman, C. Pektaş, A.M. Cengiz, T.B. Tansoker, I. Işler, V. Cevik, M. Mutlu, D. Ozben, V. Ozmen, B.B. Bayram, S. Yolcu, S. Kobal, B.B. Toto, Ö.F. Çakaloğlu, H.C. Karabulut, K. Mutlu, V. Ozkan, B.B. Celik, S. Semiz, A. Bodur, S. Gül, E. Murutoglu, B. Yildirim, R. Baki, B.E. Arslan, E. Ulusahin, M. Guner, A. Walker, N. Shrimanker, N. Stoddart, M. Cole, S. Breslin, R. Srinivasan, R. Elshaer, M. Hunter, K. Al-Bahrani, A. Liew, I. Mairs, N.G. Rocke, A. Dick, L. Qureshi, M. Chowdhury, D. Wright, N. Skerritt, C. Ho, A. Dissanayake, T. Tennakoon, A. Ali, W. Lim, S.J. Tan, C. O'Neill, S. Jones, C. Knight, S. Nassif, D. Sharma, A. Warren, O. White, R. Mehdi, A. Post, N. Kalakouti, E. Dashnyam, E. Stourton, F. Mykoniatis, I. Currow, C. Wong, F. Gupta, A. Shatkar, V. Luck, J. Kadiwar, S. Smedley, A. Wakefield, R. Herrod, P. Blackwell, J. Lund, J. Cohen, F. Bandi, A. Giuliani, S. Bond-Smith, G. Pezas, T. Farhangmehr, N. Urbonas, T. Perenyei, M. Ireland, P. Blencowe, N. Bowling, K. Bunting, D. Longstaff, L. Smart, N. Keogh, K. Jeon, H. Iqbal, M.R. Khosla, S. Jeffery, A. Perera, J. Teasdale, E. Ibrahem, A.A. Alhammali, T. Salama, Y. Kabariti, R. Oram, S. Kidd, T. Cullen, F. Owen, C. Wilson, M. Chiu, S. Sarafilovic, H. Ploski, J. Evans, E. Abbas, A. Kamya, S. Ishak, N. Bisset, C. Andress, C. Chin, Y.R. Patel, P. Evans, D. Jeffery, A. Perera, J. Haslegrave, A. Boggon, A. Laurie, K. Connor, K. Mann, T. Nepogodiev, D. Mansuri, A. Davies, R. Griffiths, E. Shahbaz, A.R. Eng, C. Din, F. Heveder, A.L. Park, E.H.G. Ravishankar, R. McIntosh, K. Yau, J.D. Chan, L. McGarvie, S. Tang, L. Lim, H. Yap, S. Park, J. Ng, Z. Mirza, S. Ang, Y.L. Walls, L. Teasdale, E. Roy, C. Paterson-Brown, S. Camilleri-Brennan, J. McLean, K. D'Souza, M. Pronin, S. Henshall, D.E. Ter, E. Fouad, D. Minocha, A. English, W. Morgan, C. Townsend, D. Maciejec, L. Mahdi, S. Akpenyi, O. Hall, E. Caydiid, H. Rob, Z. Abbott, T. Torrance, H.D. Irwin, G. Johnston, R. Gani, M. Gravante, G. Rajmohan, S. Majid, K. Dindyal, S. Smith, C. Palliyil, M. Patel, S. Nicholson, L. Harvey, N. Baillie, K. Shillito, S. Kershaw, S. Bamford, R. Orton, P. Reunis, E. Tyler, R. Soon, W. Jama, G.M. Dhillon, D. Patel, K. Nanthakumaran, S. Heard, R. Chen, K.Y. Barmayehvar, B. Datta, U. Kamarajah, S.K. Iftekhartani, S. Monaghan, E. Donnelly, P. Walker, M. Parakh, J. Blacker, S. Kaul, A. Paramasivan, A. Farag, S. Nessa, A. Awadallah, S. Lim, J. Cheankhunng, J. Gash, K. Kiran, R.P. Murray, A. Etchill, E. Dasari, M. Puyana, J. Haddad, N. Zielinski, M. Choudhry, A. Caliman, C. Beamon, M. Duane, T. Narayanan, R. Swaroop, M. Myers, J. Deal, R. Schadde, E. Hemmila, M. Napolitano, L. To, K. Makupe, A. Musowoya, J. Maimbo, M. van der Naald, N. Kumwenda, D. Reece-Smith, A. Otten, K. Verbeek, A. Prins, M. Suarez, A.A.B. Balmaceda, R. Deane, C. Dijan, E. Elfiky, M. Koskenvuo, L. Thollot, A. Limoges, B. Capito, C. Alexandre, C. Kotobi, H. Leroux, J. Rod, J. Pinnagoda, K. Henric, N. Azzis, O. Rosello, O. Francois, P. Etienne, S. Buisson, P. Hmila, S. Clegg-Lamptey, J.-N. Imoro, O. Abem, O.E. Wondoh, P. Papageorgiou, D. Soulou, V. Asturias, S. Peña, L. Connor, D.B.O. Luc, A.R. Russo, A.A. Ruzzenente, A. Taddei, A. Cona, C. Bottini, C. Pascale, G. Rotunno, G. Solaini, L. Pascale, M.M. Notarnicola, M. Corbellino, M. Sacco, M. Ubiali, P. Cautiero, R. Bocchetti, T. Muzio, E. Guglielmo, V. Morandi, E. Mao, P. de Luca, E. Ali, F.M. Žilinskas, J. Strupas, K. Kondrotas, P. Baltrunas, R. Kutkevicius, J. Ignatavicius, P. Tan, C.L. Siaw, J.Y. Yam, S.Y. Wilson, L. Aziz, M.R.A. Bondin, J. Zorrilla, C.D. Majbar, A. Sale, D. Abdullahi, L. Osagie, O. Faboya, O. Fatuga, A. Taiwo, A. Nwabuoku, E. Bliksøen, M. Khan, Z.A. Coronel, J. Miranda, C. Vasquez, I. Helguero-Santin, L.M. Rickard, J. Adedeji, A. Alqahtani, S. Rath, M. van Niekerk, M. Koto, M.Z. Matos-Puig, R. Israelsson, L. Schuetz, T. Yuksek, M.A. Mericliler, M. Uluşahin, M. Wolf, B. Fairfield, C. Yong, G.L. Whitehurst, K. Wilson, M. Redgrave, N. Musyoka, C.K. Olivier, J. Lee, K. Cox, M. Farhan-Alanie, M.M.H. Callan, R. Chibuye, C. Ali, T.H.A. Rekhis, S. Rommaneh, M. Sam, Z.H. Lawani, I. Pugliesi, T.B. Pardo, G. GlobalSurg Collaborative

Abstract

Introduction Surgical site infection (SSI) is one of the most common healthcare-associated infections (HAIs). However, there is a lack of data available about SSI in children worldwide, especially from low-income and middle-income countries. This study aimed to estimate the incidence of SSI in children and associations between SSI and morbidity across human development settings. Methods A multicentre, international, prospective, validated cohort study of children aged under 16 years undergoing clean-contaminated, contaminated or dirty gastrointestinal surgery. Any hospital in the world providing paediatric surgery was eligible to contribute data between January and July 2016. The primary outcome was the incidence of SSI by 30 days. Relationships between explanatory variables and SSI were examined using multilevel logistic regression. Countries were stratified into high development, middle development and low development groups using the United Nations Human Development Index (HDI). Results Of 1159 children across 181 hospitals in 51 countries, 523 (45·1%) children were from high HDI, 397 (34·2%) from middle HDI and 239 (20·6%) from low HDI countries. The 30-day SSI rate was 6.3% (33/523) in high HDI, 12·8% (51/397) in middle HDI and 24·7% (59/239) in low HDI countries. SSI was associated with higher incidence of 30-day mortality, intervention, organ-space infection and other HAIs, with the highest rates seen in low HDI countries. Median length of stay in patients who had an SSI was longer (7.0 days), compared with 3.0 days in patients who did not have an SSI. Use of laparoscopy was associated with significantly lower SSI rates, even after accounting for HDI. Conclusion The odds of SSI in children is nearly four times greater in low HDI compared with high HDI countries. Policies to reduce SSI should be prioritised as part of the wider global agenda. ©

Published
2020

45. TOI-532b: The Habitable-zone Planet Finder confirms a Large Super Neptune in the Neptune Desert orbiting a metal-rich M-dwarf host

Author

Arvind F. Gupta, Maria Schutte, Fred Hearty, Christian Schwab, Joe P. Ninan, Sinclaire Jones, Andrew J. Metcalf, Paul Robertson, Jason Rothenberg, Samuel Halverson, Gudmundur Stefansson, Andrew J. Monson, Jason T. Wright, Arpita Roy, Scott A. Diddams, Suzanne L. Hawley, Lawrence W. Ramsey, Jack Lubin, Ravi Kumar Kopparapu, Shubham Kanodia, Brock A. Parker, John Wisniewski, Andrea S. J. Lin, Corey Beard, Marissa Maney, William D. Cochran, Leslie Hebb, Ryan Terrien, Henry A. Kobulnicky, Chad F. Bender, Caleb I. Cañas, Connor Fredrick, and Suvrath Mahadevan

Subjects
Earth and Planetary Astrophysics (astro-ph.EP), Physics, Gas giant, Metallicity, Dwarf planet, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Light curve, Radial velocity, Space and Planetary Science, Neptune, Planet, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - Instrumentation and Methods for Astrophysics, Instrumentation and Methods for Astrophysics (astro-ph.IM), Circumstellar habitable zone, Astrophysics::Galaxy Astrophysics, Astrophysics - Earth and Planetary Astrophysics
Abstract

We confirm the planetary nature of TOI-532b, using a combination of precise near-infrared radial velocities with the Habitable-zone Planet Finder, TESS light curves, ground based photometric follow-up, and high-contrast imaging. TOI-532 is a faint (J$\sim 11.5$) metal-rich M dwarf with Teff = $3957\pm69$ K and [Fe/H] = $0.38\pm0.04$; it hosts a transiting gaseous planet with a period of $\sim 2.3$ days. Joint fitting of the radial velocities with the TESS and ground-based transits reveal a planet with radius of $5.82\pm0.19$ R$_{\oplus}$, and a mass of $61.5_{-9.3}^{+9.7}$ M$_{\oplus}$. TOI-532b is the largest and most massive super Neptune detected around an M dwarf with both mass and radius measurements, and it bridges the gap between the Neptune-sized planets and the heavier Jovian planets known to orbit M dwarfs. It also follows the previously noted trend between gas giants and host star metallicity for M dwarf planets. In addition, it is situated at the edge of the Neptune desert in the Radius--Insolation plane, helping place constraints on the mechanisms responsible for sculpting this region of planetary parameter space., 19 pages, 9 figures, 4 tables. arXiv admin note: text overlap with arXiv:2006.14546

Published
2021

46. Megacities and rivers: Scalar mismatches between urban water management and river basin management

Author

van den Brandeler, F. Gupta, J. Hordijk, M. and van den Brandeler, F. Gupta, J. Hordijk, M.

Abstract

Due to rapid urbanization, population growth and economic drivers, megacities and metropolises around the world face increasing water challenges, such as water scarcity, degradation of water resources and water-related risks such as flooding. Climate change is expected to put additional stress on already strained metropolitan water management systems. Although there is considerable research on river basin management and on urban water management, there is hardly any on metropolitan water management. Similarly, as urban water generally emerges from and returns to river basins, it is surprising how little literature there is that explicitly connects these two spheres of governance. Hence this review paper addresses the: What does a review of the literature tell us about the overlap and reconciliation between the concepts of Integrated Water Resources/River Basin Management and Metropolitan/Urban Water Management, particularly in relation to megacities? Based on an extensive literature review, this paper concludes that the key differences between the two are in relation to their overarching framework, scope, inputs and outputs of water and in relation to dealing with extreme weather events. The literature review reveals how sustainable and integrated urban water management increasingly adopt principles and rhetoric from integrated water resource management, this has yet to translate into significant changing practices on the ground. Urban water management still often occurs independently of river basin issues. Achieving coherence between river basin management and sustainable/integrated urban water management is even more difficult in metropolises and megacities, because the latter consists of multiple political-administrative units. The article concludes that the scalar mismatch between river basin management and metropolitan/megacity water governance deserves much greater attention than it currently receives in the academic and policy debates.

Published
2019
Full Text
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47. Gamma Glutamyltransferase Reduction Is Associated With Favorable Outcomes in Pediatric Primary Sclerosing Cholangitis

Author

Deneau, M.R. Mack, C. Abdou, R. Amin, M. Amir, A. Auth, M. Bazerbachi, F. Marie Broderick, A. Chan, A. DiGuglielmo, M. El-Matary, W. El-Youssef, M. Ferrari, F. Furuya, K.N. Gottrand, F. Gupta, N. Homan, M. Jensen, M.K. Kamath, B.M. Mo Kim, K. Kolho, K.-L. Konidari, A. Koot, B. Iorio, R. Martinez, M. Mohan, P. Palle, S. Papadopoulou, A. Ricciuto, A. Saubermann, L. Sathya, P. Shteyer, E. Smolka, V. Tanaka, A. Valentino, P.L. Varier, R. Venkat, V. Vitola, B. Vos, M.B. Woynarowski, M. Yap, J. Miloh, T.

Subjects
digestive system, digestive system diseases
Abstract

Adverse clinical events in primary sclerosing cholangitis (PSC) happen too slowly to capture during clinical trials. Surrogate endpoints are needed, but no such validated endpoints exist for children with PSC. We evaluated the association between gamma glutamyltransferase (GGT) reduction and long-term outcomes in pediatric PSC patients. We evaluated GGT normalization (< 50 IU/L) at 1 year among a multicenter cohort of children with PSC who did or did not receive treatment with ursodeoxycholic acid (UDCA). We compared rates of event-free survival (no portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or liver-related death) at 5 years. Of the 287 children, mean age of 11.4 years old, UDCA was used in 81% at a mean dose of 17 mg/kg/day. Treated and untreated groups had similar GGT at diagnosis (314 versus 300, P= not significant [NS]). The mean GGT was reduced at 1 year in both groups, with lower values seen in treated (versus untreated) patients (99 versus 175, P= 0.002), but 5-year event-free survival was similar (74% versus 77%, P= NS). In patients with GGT normalization (versus no normalization) by 1 year, regardless of UDCA treatment status, 5-year event-free survival was better (91% versus 67%, P< 0.001). Similarly, larger reduction in GGT over 1 year (> 75% versus < 25% reduction) was also associated with improved outcome (5-year event-free survival 88% versus 61%, P= 0.005). Conclusion:A GGT < 50 and/or GGT reduction of > 75% by 1 year after PSC diagnosis predicts favorable 5-year outcomes in children. GGT has promise as a potential surrogate endpoint in future clinical trials for pediatric PSC. © 2018 The Authors. Hepatology Communications published by Wiley Periodicals, Inc., on behalf of the American Association for the Study of Liver Diseases.

Published
2018

48. The natural history of primary sclerosing cholangitis in 781 children: A multicenter, international collaboration

Author

Deneau, M.R. El-Matary, W. Valentino, P.L. Abdou, R. Alqoaer, K. Amin, M. Amir, A.Z. Auth, M. Bazerbachi, F. Broderick, A. Chan, A. Cotter, J. Doan, S. El-Youssef, M. Ferrari, F. Furuya, K.N. Gottrand, M. Gottrand, F. Gupta, N. Homan, M. Kamath, B.M. Kim, K.M. Kolho, K.-L. Konidari, A. Koot, B. Iorio, R. Ledder, O. Mack, C. Martinez, M. Miloh, T. Mohan, P. O'Cathain, N. Papadopoulou, A. Ricciuto, A. Saubermann, L. Sathya, P. Shteyer, E. Smolka, V. Tanaka, A. Varier, R. Venkat, V. Vitola, B. Vos, M.B. Woynarowski, M. Yap, J. Jensen, M.K.

Subjects
digestive system diseases
Abstract

There are limited data on the natural history of primary sclerosing cholangitis (PSC) in children. We aimed to describe the disease characteristics and long-term outcomes of pediatric PSC. We retrospectively collected all pediatric PSC cases from 36 participating institutions and conducted a survival analysis from the date of PSC diagnosis to dates of diagnosis of portal hypertensive or biliary complications, cholangiocarcinoma, liver transplantation, or death. We analyzed patients grouped by disease phenotype and laboratory studies at diagnosis to identify objective predictors of long-term outcome. We identified 781 patients, median age 12 years, with 4,277 person-years of follow-up; 33% with autoimmune hepatitis, 76% with inflammatory bowel disease, and 13% with small duct PSC. Portal hypertensive and biliary complications developed in 38% and 25%, respectively, after 10 years of disease. Once these complications developed, median survival with native liver was 2.8 and 3.5 years, respectively. Cholangiocarcinoma occurred in 1%. Overall event-free survival was 70% at 5 years and 53% at 10 years. Patient groups with the most elevated total bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis had the worst outcomes. In multivariate analysis PSC–inflammatory bowel disease and small duct phenotypes were associated with favorable prognosis (hazard ratios 0.6, 95% confidence interval 0.5-0.9, and 0.7, 95% confidence interval 0.5-0.96, respectively). Age, gender, and autoimmune hepatitis overlap did not impact long-term outcome. Conclusion: PSC has a chronic, progressive course in children, and nearly half of patients develop an adverse liver outcome after 10 years of disease; elevations in bilirubin, gamma-glutamyltransferase, and aspartate aminotransferase-to-platelet ratio index at diagnosis can identify patients at highest risk; small duct PSC and PSC–inflammatory bowel disease are more favorable disease phenotypes. (Hepatology 2017;66:518–527). © 2017 by the American Association for the Study of Liver Diseases.

Published
2017

49. Measurement of mixing time and holdup of solids in gas–solid fluidized bed using radiotracer technique

Author

Harish J. Pant, Jayashree Biswal, D. F. Gupta, Sunil Goswami, and J.S. Samantray

Subjects
Gas velocity, Chemistry, Health, Toxicology and Mutagenesis, Public Health, Environmental and Occupational Health, Mixing (process engineering), Analytical chemistry, Fraction (chemistry), Gas solid, Pollution, Analytical Chemistry, Gas phase, Nuclear Energy and Engineering, Fluidized bed, Radiology, Nuclear Medicine and imaging, Spectroscopy
Abstract

Mixing times and holdup of solids were measured in a gas–solid fluidized bed using radiotracer technique. Sand and air were used as solid and gas phase, respectively in the fluidized bed. Gold-198 labeled sand particles were used as radiotracer for mixing time measurement at different operating conditions and 137Cs sealed source was used for holdup measurement at different axial and radial positions. The experiments were conducted at different operating conditions. The measured mixing times ranged from 1.4 to 21 s at different conditions. It was observed that at a particular bed height, the mixing time initially decreases with increasing gas velocity and tend to become constant at higher gas velocities. However, mixing time increases with increasing bed height. The holdup fraction of solid was found to be more towards the wall compared to the centre of the column. The study provided inputs to improve the existing design, design of a new system and scale-up of the process.

Published
2014

50. Computational Modeling of Pulverized Coal Fired Boilers

Author

Vivek V. Ranade, Devkumar F. Gupta, Vivek V. Ranade, and Devkumar F. Gupta

Subjects
Coal--Combustion--Computer simulation, Coal-fired furnaces--Computer simulation, Coal, Pulverized--Computer simulation, SCIENCE / Energy, TECHNOLOGY & ENGINEERING / Mechanical
Abstract

Harness State-of-the-Art Computational Modeling Tools Computational Modeling of Pulverized Coal Fired Boilers successfully establishes the use of computational modeling as an effective means to simulate and enhance boiler performance. This text factors in how computational flow models can provide a framework for developing a greater understanding o

Published
2015

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