The target list | ScienceGate

The discovery of transiting circumbinary planets by the Kepler mission suggests that planets can form efficiently around binary stars. None of the stellar binaries currently known to host planets has a period shorter than 7 d, despite the large number of eclipsing binaries found in the Kepler target list with periods shorter than a few days. These compact binaries are believed to have evolved from wider orbits into their current configurations via the so-called Lidov–Kozai migration mechanism, in which gravitational perturbations from a distant tertiary companion induce large-amplitude eccentricity oscillations in the binary, followed by orbital decay and circularization due to tidal dissipation in the stars. Here we explore the orbital evolution of planets around binaries undergoing orbital decay by this mechanism. We show that planets may survive and become misaligned from their host binary, or may develop erratic behavior in eccentricity, resulting in their consumption by the stars or ejection from the system as the binary decays. Our results suggest that circumbinary planets around compact binaries could still exist, and we offer predictions as to what their orbital configurations should be like.

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The TESS Input Catalog and Candidate Target List

The Astronomical Journal ◽

10.3847/1538-3881/aad050 ◽

2018 ◽

Vol 156 (3) ◽

pp. 102 ◽

Cited By ~ 178

Author(s):

Keivan G. Stassun ◽

Ryan J. Oelkers ◽

Joshua Pepper ◽

Martin Paegert ◽

Nathan De Lee ◽

...

Keyword(s):

Target List ◽

Candidate Target

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miR-548b-3p Regulates Proliferation, Apoptosis, and Mitochondrial Function by Targeting CIP2A in Hepatocellular Carcinoma

BioMed Research International ◽

10.1155/2018/7385426 ◽

2018 ◽

Vol 2018 ◽

pp. 1-9 ◽

Cited By ~ 1

Author(s):

Lin Lin ◽

Yong Wang

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Cycle ◽

Cell Growth ◽

Mitochondrial Function ◽

Luciferase Reporter ◽

Target List ◽

Downstream Target ◽

Normal Tissues ◽

Cisplatin Sensitivity ◽

Cell Cycle Transition

The roles of miR-548b-3p in the progression of hepatocellular carcinoma (HCC) remain undiscovered. This study aims to explore the roles and mechanisms of miR-548b-3p in HCC. Using TCGA database, we found that miR-548b-3p expression was lower in HCC compared to the normal tissues, which was further confirmed by RT-qPCR of 20 cases of surgically resected HCC and corresponding normal tissues. miR-548b-3p mimic and inhibitor were transfected into Huh7 and SK-Hep-1 cells, respectively. MTT, colony formation, and cell cycle assays showed that miR-548b-3p mimic suppressed cell growth and G1/S cell cycle transition. In contrast, miR-548b-3p inhibitor facilitated cell growth and cell cycle transition. miR-548b-3p mimic also increased cisplatin sensitivity by upregulating apoptosis rate. JC-1 staining showed that miR-548b-3p mimic downregulated mitochondrial membrane potential, while miR-548b-3p inhibitor showed the opposite effects in SK-Hep-1 cells. Using prediction software, we found that CIP2A was on the target list of miR-548b-3p. miR-548b-3p mimic downregulated CIP2A and its downstream target protein c-Myc. Luciferase reporter assay demonstrated that CIP2A was as a direct target of miR-548b-3p. CIP2A depletion partly reduced the effect of miR-548b-3p mimic/inhibitor on c-Myc. CIP2A depletion also reduced the effect of miR-548b-3p mimic/inhibitor on proliferation. In conclusion, our data demonstrated that miR-548b-3p was downregulated in HCC. miR-548b-3p regulates proliferation, apoptosis and mitochondrial function by targeting CIP2A in HCC.

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Which stars can see Earth as a transiting exoplanet?

Monthly Notices of the Royal Astronomical Society Letters ◽

10.1093/mnrasl/slaa161 ◽

2020 ◽

Vol 499 (1) ◽

pp. L111-L115

Author(s):

L Kaltenegger ◽

J Pepper

Keyword(s):

Main Sequence ◽

Line Of Sight ◽

Main Sequence Stars ◽

Target List ◽

Distant Observer ◽

Spectroscopic Observations ◽

Transiting Planets ◽

Vantage Points ◽

Life On Earth ◽

Gaia Dr2

ABSTRACT Transit observations have found the majority of exoplanets to date. Also spectroscopic observations of transits and eclipses are the most commonly used tool to characterize exoplanet atmospheres and will be used in the search for life. However, an exoplanet’s orbit must be aligned with our line of sight to observe a transit. Here, we ask, from which stellar vantage points would a distant observer be able to search for life on Earth in the same way? We use the TESS Input Catalog and data from Gaia DR2 to identify the closest stars that could see Earth as a transiting exoplanet: We identify 1004 main-sequence stars within 100 parsecs, of which 508 guarantee a minimum 10-h long observation of Earth’s transit. Our star list consists of about 77 percent M-type, 12 percent K-type, 6 percent G-type, 4 percent F-type stars, and 1 percent A-type stars close to the ecliptic. SETI searches like the Breakthrough Listen Initiative are already focusing on this part of the sky. Our catalogue now provides a target list for this search. As part of the extended mission, NASA’s TESS will also search for transiting planets in the ecliptic to find planets that could already have found life on our transiting Earth .

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Analysis of Pre and Post-MCCG 2017: Leadership Effectiveness Through the Board Nomination Committee of Top 50 Malaysian PLCs

Business Management and Strategy ◽

10.5296/bms.v11i2.17567 ◽

2020 ◽

Vol 11 (2) ◽

pp. 43

Author(s):

Dayana Mastura Baharudin ◽

Maran Marimuthu

Keyword(s):

Corporate Governance ◽

Best Practices ◽

Statistical Methods ◽

Design Methodology ◽

Annual Review ◽

Target List ◽

Corporate Governance Code ◽

Recruitment Activities ◽

The Right ◽

The Impact

Purpose – This paper investigates the impact of the two main aspects on selecting the right Board candidate including best practices within the position and structure along with the recruitment activities proposed under the Malaysian Corporate Governance Code (Code) compared across 2012 and 2017.Design/ methodology approach - For this analysis, a target list of the top 50 PLCs based on market capitalization was gathered from 784 Malaysian PLCs as of 14 August 2020. In the annual review of the reports, this study includes statistical methods to quantify and interpret the disclosures.Originality - This study reviews the developments of the policies from the Code in 2012 to the Code in 2017. Also applicable to other PLCs other than the top 50 Malaysian PLCs would be the Board Nomination Committee – Role and Structure and the Board Nomination Committee – Recruitment Activities scoring indices designed.

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Avian Immunome DB: an example of a user-friendly interface for extracting genetic information

BMC Bioinformatics ◽

10.1186/s12859-020-03764-3 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Ralf C. Mueller ◽

Nicolai Mallig ◽

Jacqueline Smith ◽

Lél Eöery ◽

Richard I. Kuo ◽

...

Keyword(s):

Bird Species ◽

Gene Symbol ◽

Immune Gene ◽

Command Line ◽

Biological Processes ◽

Command Line Interface ◽

Target List ◽

Immune Genes ◽

Front End ◽

Gene Symbols

Abstract Background Genomic and genetic studies often require a target list of genes before conducting any hypothesis testing or experimental verification. With the ever-growing number of sequenced genomes and a variety of different annotation strategies, comes the potential for ambiguous gene symbols, making it cumbersome to capture the “correct” set of genes. In this article, we present and describe the Avian Immunome DB (Avimm) for easy gene property extraction as exemplified by avian immune genes. The avian immune system is characterised by a cascade of complex biological processes underlaid by more than 1000 different genes. It is a vital trait to study particularly in birds considering that they are a significant driver in spreading zoonotic diseases. With the completion of phase II of the B10K (“Bird 10,000 Genomes”) consortium’s whole-genome sequencing effort, we have included 363 annotated bird genomes in addition to other publicly available bird genome data which serve as a valuable foundation for Avimm. Construction and content A relational database with avian immune gene evidence from Gene Ontology, Ensembl, UniProt and the B10K consortium has been designed and set up. The foundation stone or the “seed” for the initial set of avian immune genes is based on the well-studied model organism chicken (Gallus gallus). Gene annotations, different transcript isoforms, nucleotide sequences and protein information, including amino acid sequences, are included. Ambiguous gene names (symbols) are resolved within the database and linked to their canonical gene symbol. Avimm is supplemented by a command-line interface and a web front-end to query the database. Utility and discussion The internal mapping of unique gene symbol identifiers to canonical gene symbols allows for an ambiguous gene property search. The database is organised within core and feature tables, which makes it straightforward to extend for future purposes. The database design is ready to be applied to other taxa or biological processes. Currently, the database contains 1170 distinct avian immune genes with canonical gene symbols and 612 synonyms across 363 bird species. While the command-line interface readily integrates into bioinformatics pipelines, the intuitive web front-end with download functionality offers sophisticated search functionalities and tracks the origin for each record. Avimm is publicly accessible at https://avimm.ab.mpg.de.

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WR+O binaries observed from the DAO

Symposium - International Astronomical Union ◽

10.1017/s0074180900202003 ◽

1995 ◽

Vol 163 ◽

pp. 235-238

Author(s):

G.M. Hill ◽

A.B. Underhill

Keyword(s):

Primary Target ◽

Target List ◽

Long Period ◽

Eccentric Orbits ◽

Short Period

We report here the results, to date, of our monitoring of northern WR stars. New orbits have been published for the short period binaries HD 193576 and HD 214419. Of particular interest are two long period binaries with fairly eccentric orbits, HD 190918 and HD 193793. A new orbit has been determined for HD 190918. We are currently analysing spectra obtained over one cycle of the 7.9 year period of HD 193793. Other stars on our primary target list include HD 192163, HD 192641, and HD 193077.

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Know thy star, know thy planet: chemo-kinematically characterizing TESS targets

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz3255 ◽

2019 ◽

Vol 491 (3) ◽

pp. 4365-4381 ◽

Cited By ~ 5

Author(s):

Andreia Carrillo ◽

Keith Hawkins ◽

Brendan P Bowler ◽

William Cochran ◽

Andrew Vanderburg

Keyword(s):

Distribution Functions ◽

Target List ◽

Thick Disc ◽

Thin Disc ◽

Candidate Target ◽

Stellar Properties ◽

The Individual ◽

Host Stars ◽

Gaia Dr2 ◽

Kinematic Properties

ABSTRACT The Transiting Exoplanet Survey Satellite (TESS) has already begun to discover what will ultimately be thousands of exoplanets around nearby cool bright stars. These potential host stars must be well understood to accurately characterize exoplanets at the individual and population levels. We present a catalogue of the chemo-kinematic properties of 2218 434 stars in the TESS Candidate Target List using survey data from Gaia DR2, APOGEE, GALAH, RAVE, LAMOST, and photometrically derived stellar properties from SkyMapper. We compute kinematic thin disc, thick disc, and halo membership probabilities for these stars and find that though the majority of TESS targets are in the thin disc, 4 per cent of them reside in the thick disc and <1 per cent of them are in the halo. The TESS Objects of Interest in our sample also display similar contributions from the thin disc, thick disc, and halo with a majority of them being in the thin disc. We also explore metallicity and [α/Fe] distributions for each Galactic component and show that each cross-matched survey exhibits metallicity and [α/Fe] distribution functions that peak from higher to lower metallicity and lower to higher [α/Fe] from the thin disc to the halo. This catalogue will be useful to explore planet occurrence rates, among other things, with respect to kinematics, component membership, metallicity, or [α/Fe].

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A comparison analysis for the determination of stellar parameters of Ariel targets

10.5194/epsc2020-898 ◽

2020 ◽

Author(s):

Anna Brucalassi

Keyword(s):

Reference Sample ◽

Selection Strategy ◽

Spectroscopic Techniques ◽

Comparison Analysis ◽

Target List ◽

Accurate Knowledge ◽

Scientific Goal ◽

Key Factor ◽

Definition Of

&#160; &#160; &#160; Ariel has been selected as the next ESA M4 science mission and it will observe the atmospheres of a large and diversified population of transiting exoplanets. Key factor for the achievement of the scientific goal of ARIEL is the selection strategy for the definition of the input target list. A meaningful choice of the targets requires an accurate knowledge of the planet hosting star properties and this is necessary to be obtained well before the launch. We present the results of a bench-marking analysis between three different spectroscopic techniques used to determine stellar parameters for a selected number of targets belonging to the Ariel reference sample. Our goal is to consolidate a method that will be used to homogeneously determine the stellar parameters of the complete Ariel reference sample.

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