Determination of astrophysical parameters of open clusters using classical and semi-automated isochrone-fitting methods

AbstractWhen we use optical isochrone-fitting solutions from the literature to 2mass CMDs, they are often not the best solutions in the infrared domain. We analysed 10 open clusters with 2mass, nine of them previously studied with optical photometry (NGC 1245, NGC 1342, NGC 1502, NGC 2104, NGC 2204, NGC 2243, NGC 2281, NGC 6709 and NGC 744) and one using integrated spectroscopy (BH 132). The study involved the classical (by eye) and a semi-automated method of isochrone fitting. We used the solutions of the first method as input for the second, looking for refined solutions. The semi-automated method uses a synthetic color–magnitude diagram (CMD), based on different Padova isochrones, to compare with the observed CMDs by means of likelihood statistics. The derived astrophysical parameters are age, distance and reddening values. The present results show better fits than those implied by the optical values. We also show that the semi-automated method decreases the parameter uncertainties.

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In Vitro Validation of an Automated Method Based on Color Doppler Imaging for Determination of Flow Volume in the Presence of Nonflat Velocity Distributions

Journal of the American College of Cardiology ◽

10.1016/s0735-1097(97)88255-1 ◽

1998 ◽

Vol 31 (2) ◽

pp. 518A ◽

Cited By ~ 1

Author(s):

K Dennig

Keyword(s):

Color Doppler ◽

Color Doppler Imaging ◽

Doppler Imaging ◽

Flow Volume ◽

Automated Method

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An Automated Method for the Determination of Serum Calcium with Glyoxal Bis (2-Hydroxyanil)

Clinical Chemistry ◽

10.1093/clinchem/13.6.515 ◽

1967 ◽

Vol 13 (6) ◽

pp. 515-520 ◽

Cited By ~ 18

Author(s):

Genevieve Farese ◽

Janice L Schmidt ◽

Milton Mager

Keyword(s):

Serum Calcium ◽

Automated Analysis ◽

Automated Method ◽

Good Agreement

Abstract A completely automated analysis is described for the determination of serum calcium with glyoxal bis (2-hydroxyanil) solution (GBHA). The method is simple and precise, and the data obtained are in good agreement with results obtained by the manual GBHA procedure.

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Automated method for the colorimetric determination of acyl esters in serum

The Journal of Lipid Research ◽

10.1016/s0022-2275(20)38997-5 ◽

1965 ◽

Vol 6 (2) ◽

pp. 301-306

Author(s):

Arnold Antonis ◽

D.S. Platt ◽

J.M. Thorp

Keyword(s):

Colorimetric Determination ◽

Automated Method

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Gaia DR1 completeness within 250 pc & star formation history of the Solar neighbourhood

Proceedings of the International Astronomical Union ◽

10.1017/s1743921317006159 ◽

2017 ◽

Vol 12 (S330) ◽

pp. 148-151 ◽

Cited By ~ 1

Author(s):

Edouard J. Bernard

Keyword(s):

Star Formation ◽

Star Formation History ◽

Solar Neighbourhood ◽

The Sun ◽

Thick Disc ◽

Formation History ◽

Magnitude Diagram ◽

History Of

AbstractWe took advantage of the Gaia DR1 to combine TGAS parallaxes with Tycho-2 and APASS photometry to calculate the star formation history (SFH) of the solar neighbourhood within 250 pc using the colour-magnitude diagram fitting technique. We present the determination of the completeness within this volume, and compare the resulting SFH with that calculated from the Hipparcos catalogue within 80 pc of the Sun. We also show how this technique will be applied out to ~5 kpc thanks to the next Gaia data releases, which will allow us to quantify the SFH of the thin disc, thick disc and halo in situ, rather than extrapolating based on the stars from these components that are today in the solar neighbourhood.

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An HPLC-automated Derivatization for Glutathione and Related Thiols Analysis in Brassica rapa L.

Agronomy ◽

10.3390/agronomy11061157 ◽

2021 ◽

Vol 11 (6) ◽

pp. 1157

Author(s):

Francesco Nacca ◽

Concetta Cozzolino ◽

Petronia Carillo ◽

Pasqualina Woodrow ◽

Amodio Fuggi ◽

...

Keyword(s):

Brassica Rapa ◽

High Performance ◽

Internal Standard ◽

Plant Tissues ◽

Cellular Functions ◽

Sulphur Compounds ◽

Stress Protection ◽

Automated Method ◽

Reduced Forms

The high content of glucosinolates and glutathione makes the Brassicaceae an important healthy food. Thiols and especially glutathione and γ-Glu-Cys-Gly tripeptide are involved in many fundamental cellular functions such as oxidative stress protection. Although several methods for sulphur compounds analysis in biological samples are actually used, the determination of glutathione and other sulphur derivatives in plant tissues is rather problematic due to their extreme susceptibility to oxidation, which can lead to their overestimation. The aim of this work was the improvement and validation of an automated method for determination of reduced and oxidised glutathione, cysteine and γ-glutamylcysteine in plant tissues. The method consists of a fully automated pre-column derivatization of thiols based on monobromobimane reagent, a high-performance liquid chromatography derivatives separation, and a fluorimetric detection and quantification. The method was successfully applied for determination of the oxidized and reduced forms of Cys, γ-GC and GSH content in leaves, petioles, inflorescences and roots of Brassica rapa L. subsp. Sylvestris. At harvest, in freshly cut plants, the average contents of GSH/2GSSG were 840/45, 345/70 and 150/70 nmol g−1 FW for the florets, leaf blades and stems, respectively; those of Cys/2Cys were 80/12, 29/12 and 24/6 nmol g-1 FW; while those of γ-GC/γ-GCCG-γ were 8.0/4.0, and 6.0/3.0, 3.0/2.0 nmol g−1 FW, respectively. Such amounts were lower in low-sulphur-grown plants at harvest. The very low coefficient of variation between repeated tests (maximum 1.6%), the high recovery of internal standard (>96%) and the linear correlation coefficient of the calibration (R2 > 0.99) support the efficiency of this method that allowed analysing about 50 samples/die in a totally automated manner with no operator intervention. Our results show that the reported method integrations can significantly improve thiols detection via HPLC.

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Automated Fluoride Ion Determination

Annals of Clinical Biochemistry International Journal of Laboratory Medicine ◽

10.1177/000456327701400174 ◽

1977 ◽

Vol 14 (1-6) ◽

pp. 269-274 ◽

Cited By ~ 8

Author(s):

David C. Cowell

Keyword(s):

Continuous Flow ◽

Ion Concentration ◽

Fluoride Ion ◽

Selective Electrode ◽

Automated Method ◽

Electrode Response ◽

Kinetics Of ◽

Fluoride Ion Selective Electrode ◽

Flow Techniques

An automated method is described, using standard continuous flow techniques, for the determination of urine fluoride ion concentration using a fluoride ion selective electrode. It is shown that the kinetics of the electrode response to changes in fluoride ion can be used for the accurate measurement of fluoride ion concentration in urine, and that equilibration of the electrode response is not a prerequisite for the measurement of fluoride ion. Recovery experiments are in the range 83 to 90%; in-batch precision is between 0·9 and 1·6% and carryover 2·5% or less.

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