Now showing items 6397-6416 of 12955

    • The K-SF-42

      Figueredo, Aurelio José; Garcia, Rafael Antonio; Menke, J. Michael; Jacobs, W. Jake; Gladden, Paul Robert; Bianchi, JeanMarie; Patch, Emily Anne; Beck, Connie J. A.; Kavanagh, Phillip S.; Sotomayor-Peterson, Marcela; et al. (SAGE PUBLICATIONS INC, 2017-01)
      The purpose of the present article is to propose an alternative short form for the 199-item Arizona Life History Battery (ALHB), which we are calling the K-SF-42, as it contains 42 items as compared with the 20 items of the Mini-K, the short form that has been in greatest use for the past decade. These 42 items were selected from the ALHB, unlike those of the Mini-K, making direct comparisons of the relative psychometric performance of the two alternative short forms a valid and instructive exercise. A series of secondary data analyses were performed upon a recently completed five-nation cross-cultural survey, which was originally designed to assess the role of life history strategy in the etiology of interpersonal aggression. Only data from the ALHB that were collected in all five cross-cultural replications were used for the present analyses. The single immediate objective of this secondary data analysis was producing the K-SF-42 such that it would perform optimally across all five cultures sampled, and perhaps even generalize well to other modern industrial societies not currently sampled as a result of the geographic breadth of those included in the present study. A novel method, based on the use of the Cross-Sample Geometric Mean as a criterion for item selection, was used for generating such a cross-culturally valid short form.

      Obermeier, Christian; Henning, Thomas; Schlieder, Joshua E.; Crossfield, Ian J. M.; Petigura, Erik; Howard, Andrew W.; Sinukoff, Evan; Isaacson, Howard T.; Ciardi, David R.; David, Trevor J.; et al. (IOP PUBLISHING LTD, 2016-12-07)
      Open clusters have been the focus of several exoplanet surveys, but only a few planets have so far been discovered. The Kepler spacecraft revealed an abundance of small planets around small cool stars, therefore, such cluster members are prime targets for exoplanet transit searches. Kepler's new mission, K2, is targeting several open clusters and star-forming regions around the ecliptic to search for transiting planets around their low-mass constituents. Here, we report the discovery of the first transiting planet in the intermediate-age (800 Myr) Beehive cluster (Praesepe). K2-95 is a faint (Kp = 15.5 mag) M3.0 +/- 0.5 dwarf from K2's Campaign 5 with an effective temperature of 3471 +/- 124 K, approximately solar metallicity and a radius of 0.402 +/- 0.050 R-circle dot. We detected a transiting planet with a radius of 3.47(-0.53)(+0.78)R(circle plus) and an orbital period of 10.134 days. We combined photometry, medium/high-resolution spectroscopy, adaptive optics/speckle imaging, and archival survey images to rule out any false-positive detection scenarios, validate the planet, and further characterize the system. The planet's radius is very unusual as M-dwarf field stars rarely have Neptune-sized transiting planets. The comparatively large radius of K2-95b is consistent with the other recently discovered cluster planets K2-25b (Hyades) and K2-33b (Upper Scorpius), indicating systematic differences in their evolutionary states or formation. These discoveries from K2 provide a snapshot of planet formation and evolution in cluster environments and thus make excellent laboratories to test differences between field-star and cluster planet populations.
    • The K2 Galactic Caps Project – going beyond the Kepler field and ageing the Galactic disc

      Rendle, B M; Miglio, A; Chiappini, C; Valentini, M; Davies, G R; Mosser, B; Elsworth, Y; García, R A; Mathur, S; Jofré, P; et al. (OXFORD UNIV PRESS, 2019-11-04)
      Analyses of data from spectroscopic and astrometric surveys have led to conflicting results concerning the vertical characteristics of the Milky Way. Ages are often used to provide clarity, but typical uncertainties of >40 per cent from photometry restrict the validity of the inferences made. Using the Kepler APOKASC sample for context, we explore the global population trends of two K2 campaign fields (3 and 6), which extend further vertically out of the Galactic plane than APOKASC. We analyse the properties of red giant stars utilizing three asteroseismic data analysis methods to cross-check and validate detections. The Bayesian inference tool PARAM is used to determine the stellar masses, radii, and ages. Evidence of a pronounced red giant branch bump and an [a/Fe] dependence on the position of the red clump is observed from the K2 fields radius distribution. Two peaks in the age distribution centred at similar to 5 and similar to 12 Gyr are found using a sample with sigma(age) < 35 per cent. In comparison with Kepler, we find the older peak to be more prominent for K2. This age bimodality is also observed based on a chemical selection of low-[alpha/Fe] (<= 0.1) and high-[alpha/Fe] (>0.1) stars. As a function of vertical distance from the Galactic mid-plane (|Z|), the age distribution shows a transition from a young to old stellar population with increasing |Z| for the K2 fields. Further coverage of campaign targets with high-resolution spectroscopy is required to increase the yield of precise ages achievable with asteroseismology.
    • K2-138 g: Spitzer Spots a Sixth Planet for the Citizen Science System

      Hardegree-Ullman, K.K.; Christiansen, J.L.; Ciardi, D.R.; Crossfield, I.J.M.; Dressing, C.D.; Livingston, J.H.; Volk, K.; Agol, E.; Barclay, T.; Barentsen, G.; et al. (American Astronomical Society, 2021)
      K2 greatly extended Kepler's ability to find new planets, but it was typically limited to identifying transiting planets with orbital periods below 40 days. While analyzing K2 data through the Exoplanet Explorers project, citizen scientists helped discover one super-Earth and four sub-Neptune sized planets in the relatively bright (V = 12.21, K = 10.3) K2-138 system, all which orbit near 3:2 mean-motion resonances. The K2 light curve showed two additional transit events consistent with a sixth planet. Using Spitzer photometry, we validate the sixth planet's orbital period of 41.966 ± 0.006 days and measure a radius of 3.44_-0.31 +0.32, R, solidifying K2-138 as the K2 system with the most currently known planets. There is a sizeable gap between the outer two planets, since the fifth planet in the system, K2-138 f, orbits at 12.76 days. We explore the possibility of additional nontransiting planets in the gap between f and g. Due to the relative brightness of the K2-138 host star, and the near resonance of the inner planets, K2-138 could be a key benchmark system for both radial velocity and transit-timing variation mass measurements, and indeed radial velocity masses for the inner four planets have already been obtained. With its five sub-Neptunes and one super-Earth, the K2-138 system provides a unique test bed for comparative atmospheric studies of warm to temperate planets of similar size, dynamical studies of near-resonant planets, and models of planet formation and migration. © 2021. The American Astronomical Society. All rights reserved.
    • KalAO the swift adaptive optics imager on the 1.2m Euler Swiss telescope in La Silla, Chile

      Hagelberg, Janis; Restori, Nathanael; Wildi, François; Chazelas, Bruno; Baranec, Christoph; Guyon, Olivier; Genolet, Ludovic; Sordet, Michaël; Riddle, Reed; The University of Arizona (SPIE, 2020-12-13)
      KalAO is a natural guide star adaptive optics (AO) imager to be installed on the second Nasmyth focus of the 1.2m Euler Swiss telescope in La Silla, Chile. The initial design of the system is inspired on RoboAO with modifications in order to operate in natural guide star (NGS) mode. KalAO was built to search for binarity in planet hosting stars by following-up candidates primarily from the TESS satellite survey. The optical design is optimised for the 450-900 nm wavelength range and is fitted with SDSS g,r,i,z filters. The system is designed for wavefront control down to I-magnitude 11 stars in order to probe the same parameter space as radial velocity instruments such as HARPS and NIRPS. The principal components of the system are an 11x11 10.9 cm sub-apertures Electron Multiplying CCD (EMCCD) Shack-Hartmann wavefront sensor, a 140 actuators Microelectromechanical systems (MEMS) deformable mirror, a fast tip/tilt mirror, and a graphics processing unit (GPU) powered glycol cooled real-time computer. It is designed to run at up to 1.8kHz in order to detect companions as close as the 150mas visible-light diffraction limit. The real-time adaptive optics control is using the CACAO software running on GPUs. The instrument is planned for commissioning early 2021 in Chile if the covid restrictions are lifted. © 2020 SPIE.
    • Kaluza-Klein towers in the early universe: Phase transitions, relic abundances, and applications to axion cosmology

      Dienes, Keith R.; Kost, Jeff; Thomas, Brooks; Univ Arizona, Dept Phys (AMER PHYSICAL SOC, 2017-06-30)
      We study the early-universe cosmology of a Kaluza-Klein (KK) tower of scalar fields in the presence of a mass-generating phase transition, focusing on the time development of the total tower energy density (or relic abundance) as well as its distribution across the different KK modes. We find that both of these features are extremely sensitive to the details of the phase transition and can behave in a variety of ways significant for late-time cosmology. In particular, we find that the interplay between the temporal properties of the phase transition and the mixing it generates are responsible for both enhancements and suppressions in the late-time abundances, sometimes by many orders of magnitude. We map out the complete model parameter space and determine where traditional analytical approximations are valid and where they fail. In the latter cases we also provide new analytical approximations which successfully model our results. Finally, we apply this machinery to the example of an axion-like field in the bulk, mapping these phenomena over an enlarged axion parameter space that extends beyond that accessible to standard treatments. An important by-product of our analysis is the development of an alternate "UV-based" effective truncation of KK theories which has a number of interesting theoretical properties that distinguish it from the more traditional "IR-based" truncation typically used in the extra-dimension literature.
    • Kappa and lambda light chain mRNA in situ hybridization compared to flow cytometry and immunohistochemistry in B cell lymphomas

      Rimsza, Lisa; Day, William; McGinn, Sarah; Pedata, Anne; Natkunam, Yasodha; Warnke, Roger; Cook, James; Marafioti, Teresa; Grogan, Thomas; Department of Pathology, University of Arizona, Tucson, AZ, USA; et al. (BioMed Central, 2014)
      BACKGROUND:Detection of B cell clonality is useful for assisting in the diagnosis of B cell lymphomas. Clonality assessment can be accomplished through evaluation of KAPPA and LAMBDA light chain expression. Currently, only slide based methods are available for the majority of patient biopsies and do not detect light chain protein or mRNA in many B-cell lymphomas. Herein we evaluated a new method, known as colorimetric in situ hybridization (CISH), with improved sensitivity and multiplexing capacity, for its usefulness in clonality detection in mature B cell malignancies.METHODS:The KAPPA and LAMBDA ISH was performed on a Ventana Benchmark XT utilizing two color chromogenetic detection. The probes comprised 2 haptenated riboprobes each approximately 500 base pairs long directed against the conserved regions of either KAPPA or LAMBDA mRNA. The dual colors consisted of silver deposition (black) for KAPPA light chain and a novel (pink) chromogen for LAMBDA light chain. Following optimization, CISH allowed visualization of mRNA in benign B cells in reactive tissues including germinal center, mantle zone, and post-germinal center cells. We then identified 79 cases of B cell lymphoma with formalin-fixed paraffin-embedded (FFPE) biopsies including: follicular (36 cases), mantle cell (6 cases), marginal zone (12 cases), lymphoplasmacytic (6 cases), small lymphocytic (4 cases), and diffuse large B cell (15 cases), which were selected on the basis of either prior flow cytometry or immunohistochemistry (IHC) results to serve as the predicate, "gold standard," comparator.RESULTS:39/79 (49.4%) cases were classified as KAPPA and 29/79 (36.7%) as LAMBDA light chain restricted
    • A Kappa Opioid Receptor Agonist Blocks Bone Cancer Pain Without Altering Bone Loss, Tumor Size, or Cancer Cell Proliferation in a Mouse Model of Cancer-Induced Bone Pain

      Edwards, Katie A.; Havelin, Joshua J.; McIntosh, Mary I.; Ciccone, Haley A.; Pangilinan, Kathlene; Imbert, Ian; Largent-Milnes, Tally M.; King, Tamara; Vanderah, Todd W.; Streicher, John M.; et al. (CHURCHILL LIVINGSTONE, 2018-06)
      Breast cancer metastasizes to bone, diminishing quality of life of patients because of pain, fracture, and limited mobility. Cancer-induced bone pain (CIBP) is characterized as moderate to severe ongoing pain, primarily managed by mu opioid agonists such as fentanyl. However, opioids are limited by escalating doses and serious side effects. One alternative may be kappa opioid receptor (KOR) agonists. There are few studies examining KOR efficacy on CIBP, whereas KOR agonists are efficacious in peripheral and inflammatory pain. We thus examined the effects of the KOR agonist U50,488 given twice daily across 7 days to block CIBP, tumor-induced bone loss, and tumor burden. U50,488 dose-dependently blocked tumor-induced spontaneous flinching and impaired limb use, without changing tactile hypersensitivity, and was fully reversed by the KOR antagonist nor-binaltorphimine. U50,488 treatment was higher in efficacy and duration of action at later time points. U50,488 blocked this pain without altering tumor-induced bone loss or tumor growth. Follow-up studies in human cancer cell lines confirmed that KOR agonists do not affect cancer cell proliferation. These studies suggest that KOR agonists could be a new target for cancer pain management that does not induce cancer cell proliferation or alter bone loss. Perspective: This study demonstrates the efficacy of KOR agonists in the treatment of bone cancer-induced pain in mice, without changing tumor size or proliferation in cancer cell lines. This suggests that KOR agonists could be used to manage cancer pain without the drawbacks of mu opioid ago-nists and without worsening disease progression. (C) 2018 by the American Pain Society
    • Kappa opioid signaling in the right central amygdala causes hind paw specific loss of diffuse noxious inhibitory controls in experimental neuropathic pain

      Phelps, Caroline E; Navratilova, Edita; Dickenson, Anthony H; Porreca, Frank; Bannister, Kirsty; Department of Pharmacology (Wolters Klower, 2019-07-01)
      Diffuse noxious inhibitory controls (DNICs) is a pain-inhibits-pain phenomenon demonstrated in humans and animals. Diffuse noxious inhibitory control is diminished in many chronic pain states, including neuropathic pain. The efficiency of DNIC has been suggested to prospectively predict both the likelihood of pain chronification and treatment response. Little is known as to why DNIC is dysfunctional in neuropathic pain. Here, we evaluated DNIC in the rat L5/L6 spinal nerve ligation (SNL) model of chronic pain using both behavioral and electrophysiological outcomes. For behavior, nociceptive thresholds were determined using response to noxious paw pressure on both hind paws as the test stimulus before, and after, injection of a conditioning stimulus of capsaicin into the left forepaw. Functionally, the spike firing of spinal wide-dynamic-range neuronal activity was evaluated before and during noxious ear pinch, while stimulating the ipsilateral paw with von Frey hairs of increased bending force. In both assays, the DNIC response was significantly diminished in the ipsilateral (ie, injured) paw of SNL animals. However, behavioral loss of DNIC was not observed on the contralateral (ie, uninjured) paw. Systemic application of nor-binaltorphimine, a kappa opioid antagonist, did not ameliorate SNL-induced hyperalgesia but reversed loss of the behavioral DNIC response. Microinjection of nor-binaltorphimine into the right central amygdala (RCeA) of SNL rats did not affect baseline thresholds but restored DNIC both behaviorally and electrophysiologically. Cumulatively, these data suggest that net enhanced descending facilitations may be mediated by kappa opioid receptor signaling from the right central amygdala to promote diminished DNIC after neuropathy.
    • KaRMMa - Kappa reconstruction for mass mapping

      Fiedorowicz, P.; Rozo, E.; Boruah, S.S.; Chang, C.; Gatti, M.; Department of Physics, University of Arizona; Steward Observatory, University of Arizona (Oxford University Press, 2022)
      We present KaRMMa, a novel method for performing mass map reconstruction from weak-lensing surveys. We employ a fully Bayesian approach with a physically motivated lognormal prior to sample from the posterior distribution of convergence maps. We test KaRMMa on a suite of dark matter N-body simulations with simulated DES Y1-like shear observations. We show that KaRMMa outperforms the basic Kaiser-Squires mass map reconstruction in two key ways: (1) our best map point estimate has lower residuals compared to Kaiser-Squires; and (2) unlike the Kaiser-Squires reconstruction, the posterior distribution of KaRMMa maps is nearly unbiased in all summary statistics we considered, namely: one-point and two-point functions, and peak/void counts. In particular, KaRMMa successfully captures the non-Gaussian nature of the distribution of κ values in the simulated maps. We further demonstrate that the KaRMMa posteriors correctly characterize the uncertainty in all summary statistics we considered. © 2022 The Author(s).
    • KBTBD13 is an actin-binding protein that modulates muscle kinetics

      de Winter, Josine M; Molenaar, Joery P; Yuen, Michaela; van der Pijl, Robbert; Shen, Shengyi; Conijn, Stefan; van de Locht, Martijn; Willigenburg, Menne; Bogaards, Sylvia Jp; van Kleef, Esmee Sb; et al. (AMER SOC CLINICAL INVESTIGATION INC, 2020-01-06)
      The mechanisms that modulate the kinetics of muscle relaxation are critically important for muscle function. A prime example of the impact of impaired relaxation kinetics is nemaline myopathy caused by mutations in KBTBD13 (NEM6). In addition to weakness, NEM6 patients have slow muscle relaxation, compromising contractility and daily life activities. The role of KBTBD13 in muscle is unknown, and the pathomechanism underlying NEM6 is undetermined. A combination of transcranial magnetic stimulation-induced muscle relaxation, muscle fiber- and sarcomere-contractility assays, low-angle x-ray diffraction, and superresolution microscopy revealed that the impaired muscle-relaxation kinetics in NEM6 patients are caused by structural changes in the thin filament, a sarcomeric microstructure. Using homology modeling and binding and contractility assays with recombinant KBTBD13, Kbtbd13-knockout and Kbtbd13(R)(408c)-knockin mouse models, and a GFP-labeled Kbtbd13-transgenic zebrafish model, we discovered that KBTBD13 binds to actin - a major constituent of the thin filament - and that mutations in KBTBD13 cause structural changes impairing muscle-relaxation kinetics. We propose that this actin-based impaired relaxation is central to NEM6 pathology.
    • Keck Planet Imager and Characterizer: concept and phased implementation

      Mawet, D.; Wizinowich, P.; Dekany, R.; Chun, M.; Hall, D.; Cetre, S.; Guyon, O.; Wallace, J. K.; Bowler, B.; Liu, M.; et al. (SPIE-INT SOC OPTICAL ENGINEERING, 2016-07-26)
      The Keck Planet Imager and Characterizer (KPIC) is a cost-effective upgrade path to the W.M. Keck observatory (WMKO) adaptive optics (AO) system, building on the lessons learned from first and second-generation extreme AO (ExA0) coronagraphs. KPIC will explore new scientific niches in exoplanet science, while maturing critical technologies and systems for future ground-based (TMT, FELT, GMT) and space-based planet imagers (HabEx, LUVOIR). The advent of fast low-noise IR cameras (IR-APD, MKIDS, electron injectors), the rapid maturing of efficient wavefront sensing (WFS) techniques (Pyramid, Zernike), small inner working angle (IWA) coronagraphs (e.g., vortex) and associated low-order wavefront sensors (LOWFS), as well as recent breakthroughs in high contrast high resolution spectroscopy, open new direct exoplanet exploration avenues that are complementary to planet imagers such as VLT-SPHERE and the Gemini Planet Imager (GPI). For instance, the search and detailed characterization of planetary systems on solar-system scales around late-type stars, mostly beyond SPHERE and GPI's reaches, can be initiated now at WMKO.
    • Keck/NIRC2 L’-band Imaging of Jovian-mass Accreting Protoplanets around PDS 70

      Wang, Jason J.; Ginzburg, Sivan; Ren, Bin; Wallack, Nicole; Gao, Peter; Mawet, Dimitri; Bond, Charlotte Z.; Cetre, Sylvain; Wizinowich, Peter; De Rosa, Robert J.; et al. (IOP PUBLISHING LTD, 2020-05-18)
      We present L'-band imaging of the PDS 70 planetary system with Keck/NIRC2 using the new infrared pyramid wave front sensor. We detected both PDS 70 b and c in our images, as well as the front rim of the circumstellar disk. After subtracting off a model of the disk, we measured the astrometry and photometry of both planets. Placing priors based on the dynamics of the system, we estimated PDS 70 b to have a semimajor axis of 20(-4)(+3) au and PDS 70 c to have a semimajor axis of 34(-6)(+12) au (95% credible interval). We fit the spectral energy distribution (SED) of both planets. For PDS 70 b, we were able to place better constraints on the red half of its SED than previous studies and inferred the radius of the photosphere to be 2-3 R-Jup. The SED of PDS 70 c is less well constrained, with a range of total luminosities spanning an order of magnitude. With our inferred radii and luminosities, we used evolutionary models of accreting protoplanets to derive a mass of PDS 70 b between 2 and 4 M-Jup and a mean mass accretion rate between 3 x 10(-7) and 8 x 10(-7) M-Jup/yr. For PDS 70 c, we computed a mass between 1 and 3 M-Jup and mean mass accretion rate between 1 x 10(-7) and 5 x 10(-7) M-Jup/yr. The mass accretion rates imply dust accretion timescales short enough to hide strong molecular absorption features in both planets' SEDs.
    • Keck/OSIRIS paβ high-contrast imaging and updated constraints on PDS 70b

      Uyama, T.; Xie, C.; Aoyama, Y.; Beichman, C.A.; Hashimoto, J.; Dong, R.; Hasegawa, Y.; Ikoma, M.; Mawet, D.; McElwain, M.W.; et al. (American Astronomical Society, 2021)
      We present a high-contrast imaging search for Paβ line emission from protoplanets in the PDS 70 system with Keck/OSIRIS integral field spectroscopy. We applied the high-resolution spectral differential imaging technique to the OSIRIS J-band data but did not detect the Paβ line at the level predicted using the parameters of Hashimoto et al. (2020). This lack of Paβ emission suggests the MUSE-based study may have overestimated the line width of Hα. We compared our Paβ detection limits with the previous Hα flux and Hβ limits and estimated AV to be ∼0.9 and 2.0 for PDS 70 b and c, respectively. In particular, PDS 70 b's AV is much smaller than implied by highcontrast near-infrared studies, which suggests the infrared-continuum photosphere and the hydrogen-emitting regions exist at different heights above the forming planet. © 2021 Institute of Physics Publishing. All rights reserved.
    • Keep Your Politics Out of My Practice

      Robbins, Richard; University of Arizona College of Medicine - Phoenix (Arizona Thoracic Society, 2018-07-27)
      No abstract available. Article truncated at 150 words. Politicians have repeatedly inserted themselves into exam rooms and under hospital gowns, telling doctors what they can and cannot discuss with patients; forcing providers to recite scripted medical advice they know to be factually inaccurate; and even instructing physicians to prioritize the financial interests of private companies over the health of their patients (1,2). In 2011 Florida passed a sweeping law barring doctors from routinely asking patients whether they had guns in their homes, counseling them on common-sense firearm storage measures or recording any information about gun ownership in their medical files. Four states (Pennsylvania, Ohio, Colorado, and Texas) have passed legislation relating to disclosure of information about exposure to chemicals used in the process of hydraulic fracturing (“fracking”). Some new laws require physicians to discuss specific practices that may not be necessary or appropriate at the time of a specific encounter with a patient. For example, New York enacted …
    • Kelch-like ECH-associated protein 1 (KEAP1) differentially regulates nuclear factor erythroid-2–related factors 1 and 2 (NRF1 and NRF2)

      Tian, Wang; de la Vega, Montserrat Rojo; Schmidlin, Cody J.; Ooi, Aikseng; Zhang, Donna D.; Univ Arizona, Dept Pharmacol & Toxicol (AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC, 2018-02-09)
      Nuclear factor erythroid-2-related factor 1 (NRF1) and NRF2 are essential for maintaining redox homeostasis and coordinating cellular stress responses. They are highly homologous transcription factors that regulate the expression of genes bearing antioxidant-response elements (AREs). Genetic ablation of NRF1 or NRF2 results in vastly different phenotypic outcomes, implying that they play different roles and may be differentially regulated. Kelch-like ECH-associated protein 1 (KEAP1) is the main negative regulator of NRF2 and mediates ubiquitylation and degradation of NRF2 through its NRF2-ECH homology-like domain 2 (Neh2). Here, we report that KEAP1 binds to the Neh2-like (Neh2L) domain of NRF1 and stabilizes it. Consistently, NRF1 is more stable in KEAP1(+/+) than in KEAP1(-/-) isogenic cell lines, whereas NRF2 is dramatically stabilized in KEAP1(-/-) cells. Replacing NRF1's Neh2L domain with NRF2's Neh2 domain renders NRF1 sensitive to KEAP1-mediated degradation, indicating that the amino acids between the DLG and ETGE motifs, not just the motifs themselves, are essential for KEAP1-mediated degradation. Systematic site-directed mutagenesis identified the core amino acid residues required for KEAP1-mediated degradation and further indicated that the DLG and ETGE motifs with correct spacing are insufficient as a KEAP1 degron. Our results offer critical insights into our understanding of the differential regulation of NRF1 and NRF2 by KEAP1 and their different physiological roles.
    • KELT-23Ab: A Hot Jupiter Transiting a Near-solar Twin Close to the TESS and JWST Continuous Viewing Zones

      Beatty, Thomas G.; Univ Arizona, Dept Astron; Univ Arizona, Steward Observ (IOP PUBLISHING LTD, 2019-07-24)
      We announce the discovery of KELT-23Ab, a hot Jupiter transiting the relatively bright (V = 10.3) star BD+66 911 (TYC 4187-996-1), and characterize the system using follow-up photometry and spectroscopy. A global fit to the system yields host-star properties of T-eff = 5900 +/- 49 K, M* = 0.945(-0.054)(+0.060) M-circle dot, R* = 0.995 +/- 0.015 R-circle dot, L* = 1.082(-0.048)(+0.051) L-circle dot, log g* = 4.418(-0.025)(+0.026). (cgs), and [Fe/H] = -0.105 +/- 0.077. KELT-23Ab is a hot Jupiter with a mass of M-p = 0.938(-0.042)(+0.045). M-J, radius of R-p = 1.322 0.025 R-J, and density of rho(p) = 0.504(0.035)(+0.038) g cm(-3). Intense insolation flux from the star has likely caused KELT-23Ab to become inflated. The time of inferior conjunction is T-0 = 2458149.40776 +/- 0.00091 BJD(TDB) and the orbital period is P = 2.255353(-0.000030)(+0.000031) ON days. There is strong evidence that KELT-23A is a member of a long-period binary star system with a less luminous companion, and due to tidal interactions, the planet is likely to spiral into its host within roughly a gigayear. This system has one of the highest positive ecliptic latitudes of all transiting planet hosts known to date, placing it near the Transiting Planet Survey Satellite and James Webb Space Telescope continuous viewing zones. Thus we expect it to be an excellent candidate for long-term monitoring and follow up with these facilities.
    • KELT-24b: A 5M J Planet on a 5.6 day Well-aligned Orbit around the Young V = 8.3 F-star HD 93148

      Rodriguez, Joseph E.; Eastman, Jason D.; Zhou, George; Quinn, Samuel N.; Beatty, Thomas G.; Penev, Kaloyan; Johnson, Marshall C.; Cargile, Phillip A.; Latham, David W.; Bieryla, Allyson; et al. (IOP PUBLISHING LTD, 2019-10-23)
      We present the discovery of KELT-24 b, a massive hot Jupiter orbiting a bright (V = 8.3 mag, K = 7.2 mag) young F-star with a period of 5.6 days. The host star, KELT-24 (HD 93148), has a T-eff = 6509(-49)(+50) K, a mass of M-* = 1.460(-0.059)(+0.055) M-circle dot, a radius of R-* = 1.506 +/- 0.022 R-circle dot, and an age of 0.78(-0.42)(+0.61) Gyr. Its planetary companion (KELT-24 b) has a radius of R-P = 1.272 +/- 0.021 R-J and a mass of M-P = 5.18(-0.22)(+0.21) M-J, and from Doppler tomographic observations, we find that the planet's orbit is well-aligned to its host star's projected spin axis (lambda = 2.6(-3.6)(+5.1)). The young age estimated for KELT-24 suggests that it only recently started to evolve from the zero-age main sequence. KELT-24 is the brightest star known to host a transiting giant planet with a period between 5 and 10 days. Although the circularization timescale is much longer than the age of the system, we do not detect a large eccentricity or significant misalignment that is expected from dynamical migration. The brightness of its host star and its moderate surface gravity make KELT-24b an intriguing target for detailed atmospheric characterization through spectroscopic emission measurements since it would bridge the current literature results that have primarily focused on lower mass hot Jupiters and a few brown dwarfs.
    • KELT-25 b and KELT-26 b: A Hot Jupiter and a Substellar Companion Transiting Young A Stars Observed by TESS

      Martinez, Romy Rodriguez; Gaudi, B. Scott; Rodriguez, Joseph E.; Zhou, George; Labadie-Bartz, Jonathan; Quinn, Samuel N.; Penev, Kaloyan; Tan, Thiam-Guan; Latham, David W.; Paredes, Leonardo A.; et al. (IOP PUBLISHING LTD, 2020-09)
      We present the discoveries of KELT-25 b (TIC 65412605, TOI-626.01) and KELT-26 b (TIC 160708862, TOI1337.01), two transiting companions orbiting relatively bright, early A stars. The transit signals were initially detected by the KELT survey and subsequently confirmed by Transiting Exoplanet Survey Satellite (TESS) photometry. KELT-25 b is on a 4.40 day orbit around the V = 9.66 star CD-24 5016 (T-eff = 8280(-180)(+440) K, M-star = 2.18(-0.11)(+0.12) M-circle dot), while KELT-26 b is on a 3.34 day orbit around the V = 9.95 star HD 134004 (T-eff = 8640(-240)(+500) K, M-circle dot = 1.93(-0.16)(+0.14) M-circle dot), which is likely an Am star. We have confirmed the substellar nature of both companions through detailed characterization of each system using ground-based and TESS photometry, radial velocity measurements, Doppler tomography, and high-resolution imaging. For KELT-25, we determine a companion radius of R-P = 1.64(-0.043)(+0.039) R-J and a 3 sigma upper limit on the companion's mass of similar to 64 M-J. For KELT-26 b, we infer a planetary mass and radius of M-P = 1.41(-0.51)(+0.43) M-J and R-P = 1.94(-0.058)(+0.060) R-J. From Doppler tomographic observations, we find KELT-26 b to reside in a highly misaligned orbit. This conclusion is weakly corroborated by a subtle asymmetry in the transit light curve from the TESS data. KELT-25 b appears to be in a well-aligned, prograde orbit, and the system is likely a member of the cluster Theia 449.
    • KELT-9 as an Eclipsing Double-lined Spectroscopic Binary: A Unique and Self-consistent Solution to the System

      Pai Asnodkar, A.; Wang, J.; Gaudi, B.S.; Cauley, P.W.; Eastman, J.D.; Ilyin, I.; Strassmeier, K.; Beatty, T.; Department of Astronomy and Steward Observatory, University of Arizona (American Astronomical Society, 2022)
      Transiting hot Jupiters present a unique opportunity to measure absolute planetary masses due to the magnitude of their radial velocity signals and known orbital inclination. Measuring planet mass is critical to understanding atmospheric dynamics and escape under extreme stellar irradiation. Here we present the ultrahot Jupiter system KELT-9 as a double-lined spectroscopic binary. This allows us to directly and empirically constrain the mass of the star and its planetary companion without reference to any theoretical stellar evolutionary models or empirical stellar scaling relations. Using data from the PEPSI, HARPS-N, and TRES spectrographs across multiple epochs, we apply least-squares deconvolution to measure out-of-transit stellar radial velocities. With the PEPSI and HARPS-N data sets, we measure in-transit planet radial velocities using transmission spectroscopy. By fitting the circular orbital solution that captures these Keplerian motions, we recover a planetary dynamical mass of 2.17 ± 0.56 M J and stellar dynamical mass of 2.11 ± 0.78 M o˙, both of which agree with the discovery paper. Furthermore, we argue that this system, as well as systems like it, are highly overconstrained, providing multiple independent avenues for empirically cross-validating model-independent solutions to the system parameters. We also discuss the implications of this revised mass for studies of atmospheric escape. © 2022. The Author(s). Published by the American Astronomical Society..