1,422 research outputs found
Potential molecular prognostic markers for lymph node metastasis in head and neck squamous cell carcinoma
No full textDetailed stellar activity analysis and modelling of GJ 832
No full textContext. Gliese-832 (GJ 832) is an M2V star hosting a massive planet on a decade-long orbit, GJ 832b, discovered by radial velocity (RV). Later, a super Earth or mini-Neptune orbiting within the stellar habitable zone was reported (GJ 832c). The recently determined stellar rotation period (45.7 ± 9.3 days) is close to the orbital period of putative planet c (35.68 ± 0.03 days).
Aims. We aim to confirm or dismiss the planetary nature of the RV signature attributed to GJ 832c, by adding 119 new RV data points, new photometric data, and an analysis of the spectroscopic stellar activity indicators. Additionally, we update the orbital parameters of the planetary system and search for additional signals.
Methods. We performed a frequency content analysis of the RVs to search for periodic and stable signals. Radial velocity time series were modelled with Keplerians and Gaussian process (GP) regressions alongside activity indicators to subsequently compare them within a Bayesian framework.
Results. We updated the stellar rotational period of GJ 832 from activity indicators, obtaining 37.5+1.4-1.5 days, improving the precision by a factor of 6. The new photometric data are in agreement with this value. We detected an RV signal near 18 days (FAP < 4.6%), which is half of the stellar rotation period. Two Keplerians alone fail at modelling GJ 832b and a second planet with a 35-day orbital period. Moreover, the Bayesian evidence from the GP analysis of the RV data with simultaneous activity indices prefers a model without a second Keplerian, therefore negating the existence of planet c
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GJ 3929: High-precision Photometric and Doppler Characterization of an Exo-Venus and Its Hot, Mini-Neptune-mass Companion
No full textWe 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 (P b = 2.616272 ± 0.000005 days; Sb = 17.3 − 0.7 + 0.8 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 (M b = 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 R p = 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. © 2022. The Author(s). Published by the American Astronomical Society.Open access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
GJ 3090 b: one of the most favourable mini-Neptune for atmospheric characterisation
No full textWe report the detection of GJ 3090 b (TOI-177.01), a mini-Neptune on a 2.9-day orbit transiting a bright (K = 7.3 mag) M2 dwarf located at 22 pc. The planet was identified by the Transiting Exoplanet Survey Satellite and was confirmed with the High Accuracy Radial velocity Planet Searcher radial velocities. Seeing-limited photometry and speckle imaging rule out nearby eclipsing binaries. Additional transits were observed with the LCOGT, Spitzer, and ExTrA telescopes. We characterise the star to have a mass of 0.519 ± 0.013 M and a radius of 0.516 ± 0.016 R . We modelled the transit light curves and radial velocity measurements and obtained a planetary mass of 3.34 ± 0.72 ME, a radius of 2.13 ± 0.11 RE, and a mean density of 1.89+0.52 −0.45 g/cm3 . The low density of the planet implies the presence of volatiles, and its radius and insolation place it immediately above the radius valley at the lower end of the mini-Neptune cluster. A coupled atmospheric and dynamical evolution analysis of the planet is inconsistent with a pure H-He atmosphere and favours a heavy mean molecular weight atmosphere. The transmission spectroscopy metric of 221+66 −46 means that GJ 3090 b is the second or third most favourable mini-Neptune after GJ 1214 b whose atmosphere may be characterised. At almost half the mass of GJ 1214 b, GJ 3090 b is an excellent probe of the edge of the transition between super-Earths and mini-Neptunes. We identify an additional signal in the radial velocity data that we attribute to a planet candidate with an orbital period of 13 days and a mass of 17.1+8.9 −3.2 ME, whose transits are not detected.Fil: Almenara, J. M.. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Bonfils, X.. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Otegi, J. F.. Université de Genève; Suiza. Universitat Zurich; SuizaFil: Attia, O.. Université de Genève; SuizaFil: Turbet, M.. Université de Genève; SuizaFil: Astudillo Defru, Nicola. Universidad Católica de la Santísima Concepción; ChileFil: Collins, K .A.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Polanski, A. S.. University of Kansas; Estados UnidosFil: Bourrier, V.. University of Kansas; Estados UnidosFil: Hellier, C.. Keele University; Reino UnidoFil: Ziegler, C.. Stephen F. Austin State University; Estados UnidosFil: Bouchy, F.. Université de Genève; SuizaFil: Briceno, C.. Soar Telescope/nsf's Noirlab; ChileFil: Charbonneau, D.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Cointepas, M.. Université de Genève; Francia. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Collins, K .I.. George Mason University; Estados UnidosFil: Crossfield, I.. University of Kansas; Estados UnidosFil: Delfosse, X.. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Diaz, Rodrigo Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Físicas. - Universidad Nacional de San Martín. Instituto de Ciencias Físicas; Argentina. Universidad Nacional de San Martín; ArgentinaFil: Dorn, C.. Universitat Zurich; SuizaFil: Doty, J.P.. Noqsi Aerospace Ltd.; Estados UnidosFil: Forveille, T.. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Gaisné, G.. Universite Grenoble Alpes; Francia. Centre National de la Recherche Scientifique; FranciaFil: Gan, T.. Tsinghua University; ChinaFil: Myers, G.. American Association of Variable Star Observers; Estados UnidosFil: Seager, S.. Massachusetts Institute of Technology; Estados UnidosFil: Shporer, A.. Massachusetts Institute of Technology; Estados UnidosFil: Tan, T. G.. Curtin University; Australia. Perth Exoplanet Survey Telescope; AustraliaFil: Twicken, J. D.. Curtin University; Australia. National Aeronautics and Space Administration; Estados UnidosFil: Winn, J.. University of Princeton; Estados Unido
GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star
No full textUltrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 ± 0.054 Earth-radii and a mass of 0.546 ± 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 ± 2.165 grams per cubic centimeter—close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 ± 5%, similar to that of Mercury’s interior.Fil: Lam, Kristine W.F.. German Aerospace Center; Alemania. Technishe Universitat Berlin; AlemaniaFil: Csizmadia, Szilárd. German Aerospace Center; AlemaniaFil: Astudillo Defru, Nicola. Universidad Católica de la Santísima Concepción; ChileFil: Bonfils, Xavier. Universite Grenoble Alpes; FranciaFil: Gandolfi, Davide. Università di Torino; ItaliaFil: Padovan, Sebastiano. European Organisation for the Exploitation of Meteorological Satellites; Alemania. German Aerospace Center; AlemaniaFil: Esposito, Massimiliano. Thüringer Landessternwarte Tautenburg; AlemaniaFil: Hellier, Coel. Keele University; Reino UnidoFil: Hirano, Teruyuki. Tokyo Institute Of Technology; JapónFil: Livingston, John. The University Of Tokyo; JapónFil: Murgas, Felipe. Instituto Astrofisico de Canarias; España. Universidad de La Laguna; EspañaFil: Smith, Alexis M.S.. German Aerospace Center; AlemaniaFil: Collins, Karen A.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Mathur, Savita. Instituto Astrofisico de Canarias; España. Universidad de La Laguna; EspañaFil: Garcia, Rafael A.. Universite Paris-Saclay;Fil: Howell, Steve B.. NASA Ames Research Center; Estados UnidosFil: Santos, Nuno C.. Universidad de Porto; PortugalFil: Dai, Fei. California Institute of Technology; Estados UnidosFil: Ricker, George R.. Massachusetts Institute of Technology; Estados UnidosFil: Vanderspek, Roland. Massachusetts Institute of Technology; Estados UnidosFil: Latham, David W.. Harvard-Smithsonian Center for Astrophysics; Estados UnidosFil: Seager, Sara. Massachusetts Institute of Technology; Estados UnidosFil: Winn, Joshua N.. University of Princeton; Estados UnidosFil: Jenkins, Jon M.. Nasa Ames Research Center; Estados UnidosFil: Albrecht, Simon. University Aarhus; DinamarcaFil: Almenara, Jose M.. Universite Grenoble Alpes; FranciaFil: Artigau, Etienne. Universite Grenoble Alpes; FranciaFil: Barragán, Oscar. University of Oxford; Reino UnidoFil: Bouchy, François. Universidad de Ginebra; SuizaFil: Cabrera, Juan. Universite Grenoble Alpes; FranciaFil: Diaz, Rodrigo Fernando. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ciencias Físicas. - Universidad Nacional de San Martín. Instituto de Ciencias Físicas; Argentin
TUNEL labeling in retinal explants treated with GJ blockers.
No full text<p>Retinal explants were cultured for 4 hours with (A) PBS, (B) carbenoxolone (CBX), (C) quinine (Quin) and (D) CBX 100 µM + quinine 100 µM. Transverse sections of chick retina explants were submitted to terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) to characterize apoptotic spatial pattern. In each image it is possible to localize the focus of the lesion (arrows). (E–H) In order to determine whether GJ blockers caused changes in the distribution of apoptotic cells, we have counted the number of TUNEL- positive nuclei located as far as 150 µm away from the focus of the lesion. Values were plotted according to the distance of the focus, and were submitted to linear regression using the least square approach, generating mathematical parameters such as <i>R<sup>2</sup></i>, <i>R</i> and also first order equation (<i>y = ax + b</i>). (I–L) The same procedure was undertaken using values from pixel analysis. <i>X–Y</i> axis bitmap analysis was used to view the pixel values in numeric format, where values correspond to the brightness of the pixels. (M) Considering the distribution of TUNEL-positive nuclei, the means of angular coefficient from first order equation (<i>a</i>) were calculated for each experimental condition (n = 3). When compared to the control (PBS), the means of <i>a</i> angular coefficient were higher for all evaluated conditions using GJ blockers (CBX, quinine and CBX + quinine). (N) Regarding values from bitmap pixel analysis, we observed that the means of <i>a</i> angular coefficient were higher for quinine and CBX + quinine conditions. *<i>P</i><0.01 and **<i>P</i><0.05 vs. PBS in Newman-Keuls pairwise comparisons after one-way ANOVA. Scale bar: 60 µm.</p
GJ 367b: A dense, ultrashort-period sub-Earth planet transiting a nearby red dwarf star
No full textInternational audienceUltrashort-period (USP) exoplanets have orbital periods shorter than 1 day. Precise masses and radii of USP exoplanets could provide constraints on their unknown formation and evolution processes. We report the detection and characterization of the USP planet GJ 367b using high-precision photometry and radial velocity observations. GJ 367b orbits a bright (V-band magnitude of 10.2), nearby, and red (M-type) dwarf star every 7.7 hours. GJ 367b has a radius of 0.718 ± 0.054 Earth-radii and a mass of 0.546 ± 0.078 Earth-masses, making it a sub-Earth planet. The corresponding bulk density is 8.106 ± 2.165 grams per cubic centimeter—close to that of iron. An interior structure model predicts that the planet has an iron core radius fraction of 86 ± 5%, similar to that of Mercury’s interior
The Optimization of the Performance Management for Operators in GJ Company Xiamen
No full text本文以绩效管理的基本理论和GJ厦门厂的实际情况为基础，分析了GJ厦门厂一线作业员绩效管理的问题点，并结合公司目前的实际情况提出一线作业员的绩效管理改善方案。该方案以平衡计分卡的绩效管理体系为逻辑，将公司的战略目标分解到制造处，再分解至一线作业员，让作业员的绩效也能从财务面、客户面、内部运营面、学习成长面四个维度上对公司的战略发展起到支撑作用，以促进组织战略目标的实现。 在绩效管理改进方案中，作者特别强调沟通在绩效管理过程中的重要作用，它贯穿了绩效管理的整个过程。沟通有助于促进员工个人绩效的提升和员工个人的成长，从而提升组织的整体效益。 根据GJ厦门厂的实际情况，将一线作业员的绩效考核结...In this paper, operators’ performance management problems in GJ Company are analyzed based on the basic theory of performance management and the real situation of the company. The author propose to break down the company’s strategic targets to lower levels with balanced scorecard system by four levels of financial, customer, internal operation, learning and developing. So that operators’ performa...学位：管理学硕士院系专业：管理学院_工商管理硕士(工商管理硕士)学号：1792012115103
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