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Trees are partial orders in which every element has a linearly ordered set of predecessors. Here we initiate the exploration of the structural theory of trees with the study of different notions of \emph{branching in trees} and of…

Combinatorics · Mathematics 2023-01-18 Valentin Goranko , Ruaan Kellerman , Alberto Zanardo

Abundances of Mg, Ca, Sc, Cr, Fe, and Ni are derived for A stars of five nearby open clusters of various ages using high resolution spectroscopy. We point out a correlation between the abundance of Ca and that of Sc, suggesting that the…

Astrophysics · Physics 2007-05-23 A. Hui-Bon-Hoa

Star clusters have long been used to illuminate both stellar evolution and Galactic evolution. They also hold clues to the chemical and nucleosynthetic processes throughout the history of the Galaxy. We have taken high signal-to-noise,…

Solar and Stellar Astrophysics · Physics 2015-06-16 Ann Merchant Boesgaard , Brian W. Roper , Michael G. Lum

A closed-form formula is derived for the number of occurrences of matches of a multiset of patterns among all ordered (plane-planted) trees with a given number of edges. A pattern looks like a tree, with internal nodes and leaves, but also…

Discrete Mathematics · Computer Science 2020-06-30 Nachum Dershowitz

In this paper, we employ Probabilistic Neural Network (PNN) with image and data processing techniques to implement a general purpose automated leaf recognition algorithm. 12 leaf features are extracted and orthogonalized into 5 principal…

Artificial Intelligence · Computer Science 2007-07-31 Stephen Gang Wu , Forrest Sheng Bao , Eric You Xu , Yu-Xuan Wang , Yi-Fan Chang , Qiao-Liang Xiang

The results of determining the metallicity, age, helium mass fraction (Y) and abundances of the elements C, N, Mg, Ca, Mn, Ti and Cr by moderate resolution spectra for four globular clusters in the galaxy M 31: Bol 6, Bol 20, Bol 45 and Bol…

Astrophysics of Galaxies · Physics 2022-01-19 M. I. Maricheva

The aim of this paper is to characterise the abundance patterns of five iron-peak elements (Mn, Fe, Ni, Cu, and Zn) for which the stellar origin and chemical evolution are still debated. We automatically derived iron peak (Mn, Fe, Ni, Cu,…

Solar and Stellar Astrophysics · Physics 2017-10-10 Š. Mikolaitis , P. de Laverny , A. Recio-Blanco , V. Hill , C. C. Worley , M. de Pascale

This paper proposes a joint analysis of variations of global sea-level pressure and of Earth's rotation (RP), expressed as the coordinates of the rotation pole and length of day. Sea-Level-Pressure (SLP) extracted components are a weak…

Geophysics · Physics 2023-01-20 V. Courtillot , J-L. Le Mouël , F. Lopes , D. Gibert

We present ages, [Fe/H] and abundances of the alpha elements Ca I, Si I, Ti I, Ti II, and light elements Mg I, Na I, and Al I for 31 globular clusters in M31, which were obtained from high resolution, high signal-to-noise ratio (SNR$>60$)…

Astrophysics of Galaxies · Physics 2015-06-23 J. E. Colucci , R. A. Bernstein , J. Cohen

A study of gas-phase element abundances reported in the literature for 17 different elements sampled over 243 sight lines in the local part of our Galaxy reveals that the depletions into solid form (dust grains) are extremely well…

Astrophysics of Galaxies · Physics 2009-07-22 Edward B. Jenkins

We present families of combinatorial classes described as trees with nodes that can carry one of two types of "flowers": integer partitions or integer compositions. Two parameters on the flowers of trees will be considered: the number of…

Combinatorics · Mathematics 2024-03-05 Ricardo Gómez Aíza

Apple(\textit{Malus domestica} Borkh.) trees are deciduous, shedding leaves each year. This process is preceded by a gradual change in leaf color from green to yellow as chlorophyll is degraded prior to abscission. The initiation and rate…

Circular polarization spectroscopy has proven to be an indispensable tool in photosynthesis research and (bio)-molecular research in general. Oxygenic photosystems typically display an asymmetric Cotton effect around the chlorophyll…

We provide a local probabilistic description of the limiting statistics of large preferential attachment trees in terms of the ordinary degree (number of neighbors) but augmented with information on leafdegree (number of neighbors that are…

Statistical Mechanics · Physics 2026-02-03 Harrison Hartle , P. L. Krapivsky

We use very deep spectra obtained with the Ultraviolet-Visual Echelle Spectrograph in the Very Large Telescope in order to determine the physical conditions, the chemical abundances and the iron depletion factors of four H II regions of the…

Astrophysics of Galaxies · Physics 2017-01-11 G. Domínguez-Guzmán , M. Rodríguez , C. Esteban , J. García-Rojas

Leaves and flowers frequently have a characteristic rippling pattern at their edges. Recent experiments found similar patterns in torn plastic. These patterns can be reproduced by imposing metrics upon thin sheets. The goal of this paper is…

Soft Condensed Matter · Physics 2022-10-12 M. Marder

Spectropolarimetry of intact plant leaves allows to probe the molecular architecture of vegetation photosynthesis in a non-invasive and non-destructive way and, as such, can offer a wealth of physiological information. In addition to the…

Globular clusters (GCs) are key to understanding the formation and evolution of our Galaxy. While the abundances of light and Fe-peak elements in GCs have been widely studied, investigations into heavier, neutron-capture elements -- and…

In fulfilling the aims of the planetary and asteroseismic research missions, such as that of the NASA Transiting Exoplanet Survey Satellite (TESS) space telescope, accurate stellar atmospheric parameters and a detailed chemical composition…

Some studies of stars' multi-element abundance distributions suggest at least 5-7 significant dimensions, but others show that many elemental abundances can be predicted to high accuracy from [Fe/H] and [Mg/Fe] (or [Fe/H] and age) alone. We…

Astrophysics of Galaxies · Physics 2022-03-30 Yuan-Sen Ting , David H. Weinberg