The morphological transformation of red sequence galaxies in the distant cluster XMMU J1229+0151

AbstractIn this work, we study the properties of galaxies that are showing the inside-out assembly (which we call inside-out assembled galaxies; IOAGs), with the main aim to understand better their properties and morphological transformation. We analysed a sample of galaxies from the Sloan Digital Sky Survey (SDSS) Data Release 8 (DR8), with stellar masses in the range log M* = 10.73 – 11.03 M⊙ at at z < 0.1, and analyze their location in the stellar mass-SFR and the color-stellar mass diagram. We found that IOAGs have different spectroscopic properties, most of them being classified either as AGN or composite. We found that the majority of our sources are located below the main sequence of star formation in the SFR-stellar mass diagram, and in the green valley or red sequence in the color-stellar mass diagram. We argue that IOAGs seem to correspond to the transition area where the galaxies are moving from star-forming to quiescent, and from the blue cloud to the red sequence and/or to recently quenched galaxies.

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The morphological transformation of red sequence galaxies in clusters since z ∼ 1

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stx1687 ◽

2017 ◽

Vol 472 (1) ◽

pp. 254-272 ◽

Cited By ~ 9

Author(s):

P. Cerulo ◽

W. J. Couch ◽

C. Lidman ◽

R. Demarco ◽

M. Huertas-Company ◽

...

Keyword(s):

Morphological Transformation ◽

Red Sequence

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AGN and star formation properties of inside–out assembled galaxy candidates at z < 0.1

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa2488 ◽

2020 ◽

Vol 498 (3) ◽

pp. 4345-4355

Author(s):

Dejene Zewdie ◽

Mirjana Pović ◽

Manuel Aravena ◽

Roberto J Assef ◽

Asrate Gaulle

Keyword(s):

Star Formation ◽

Main Sequence ◽

Mass Range ◽

Central Star ◽

Morphological Transformation ◽

Star Forming ◽

The Galaxy ◽

High Fraction ◽

Inside Out ◽

Red Sequence

ABSTRACT We study a sample of 48 127 galaxies selected from the SDSS MPA-JHU catalogue, with log M⋆/M⊙ = 10.73−11.03 and z < 0.1. Local galaxies in this stellar mass range have been shown to have systematically shorter assembly times within their inner regions (<0.5 R50) when compared to that of the galaxy as a whole, contrary to lower or higher mass galaxies that show consistent assembly times at all radii. Hence, we refer to these galaxies as Inside-Out Assembled Galaxy (IOAG) candidates. We find that the majority of IOAG candidates with well-detected emission lines are classified as either active galactic nucleus (AGN; 40 per cent) or composite (40 per cent) in the BPT (Baldwin, Phillips & Terlevich) diagram. We also find that the majority of our sources are located below the main sequence of star formation, and within the green valley or red sequence. Most BPT-classified star-forming IOAG candidates have spiral morphologies and are in the main sequence, whereas Seyfert 2 and composites have mostly spiral morphologies but quiescent star formation rates (SFRs). We argue that a high fraction of IOAG candidates seem to be in the process of quenching, moving from the blue cloud to the red sequence. Those classified as AGN have systematically lower SFRs than star-forming galaxies, suggesting that AGN activity may be related to this quenching. However, the spiral morphology of these galaxies remains in place, suggesting that the central star formation is suppressed before the morphological transformation occurs.

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Effects of Aging on the Morphology of Rubber-Brass Interfacial Layer

Tire Science and Technology ◽

10.2346/1.3555084 ◽

2011 ◽

Vol 39 (1) ◽

pp. 20-43 ◽

Cited By ~ 7

Author(s):

A. Ashirgade ◽

P. B. Harakuni ◽

W. J. Vanooij

Keyword(s):

Chemical Composition ◽

Interfacial Layer ◽

Secondary Ion Mass Spectrometry ◽

Morphological Changes ◽

Grazing Incidence ◽

Complex Nature ◽

Rubber Compound ◽

Tire Cord ◽

Morphological Transformation ◽

Adhesion Promoter

Abstract Adhesion between rubber compound and brass-plated steel tire cord is crucial in governing the overall performance of tires. The rubber-brass interfacial adhesion is influenced by the chemical composition and thickness of the interfacial layer. It has been shown that the interfacial layer consists mainly of sulfides and oxides of copper and zinc. This paper discusses the effect of changes in the chemical composition and the structure of the interfacial layers due to addition of adhesion promoter resins. Grazing incidence x-ray diffraction (GIXRD) experiments were run on sulfidized polished brass coupons previously bonded to five experimental rubber compounds. It was confirmed that heat and humidity conditions lead to physical and chemical changes of the rubber-steel tire cord interfacial layer, closely related to the degree of rubber-brass adhesion. Morphological transformation of the interfacial layer led to loss of adhesion after aging. The adhesion promoter resins inhibit unfavorable morphological changes in the interfacial layer, thus stabilizing it during aging and prolonging failure. Tire cord adhesion tests illustrated that the one-component resins improved adhesion after aging using a rubber compound with lower cobalt loading. Based on the acquired diffraction profiles, these resins were also found to impede crystallization of the sulfide layer after aging, leading to improved adhesion. Secondary ion mass spectrometry depth profiles and scanning electron microscopy micrographs strongly corroborated the findings from GIXRD. This interfacial analysis adds valuable information to our understanding of the complex nature of the rubber-brass bonding mechanism.

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Myricetin as an Antivirulence Compound Interfering with a Morphological Transformation into Coccoid Forms and Potentiating Activity of Antibiotics against Helicobacter pylori

International Journal of Molecular Sciences ◽

10.3390/ijms22052695 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2695

Author(s):

Paweł Krzyżek ◽

Paweł Migdał ◽

Emil Paluch ◽

Magdalena Karwańska ◽

Alina Wieliczko ◽

...

Keyword(s):

Helicobacter Pylori ◽

Biofilm Formation ◽

Inhibitory Effect ◽

Morphological Transformation ◽

High Tendency ◽

Minimal Inhibitory Concentrations ◽

Coccoid Form ◽

Stomach Diseases ◽

Fold Reduction ◽

H Pylori

Helicobacter pylori, a gastric pathogen associated with a broad range of stomach diseases, has a high tendency to become resistant to antibiotics. One of the most important factors related to therapeutic failures is its ability to change from a spiral to a coccoid form. Therefore, the main aim of our original article was to determine the influence of myricetin, a natural compound with an antivirulence action, on the morphological transformation of H. pylori and check the potential of myricetin to increase the activity of antibiotics against this pathogen. We observed that sub-minimal inhibitory concentrations (sub-MICs) of this compound have the ability to slow down the process of transformation into coccoid forms and reduce biofilm formation of this bacterium. Using checkerboard assays, we noticed that the exposure of H. pylori to sub-MICs of myricetin enabled a 4–16-fold reduction in MICs of all classically used antibiotics (amoxicillin, clarithromycin, tetracycline, metronidazole, and levofloxacin). Additionally, RT-qPCR studies of genes related to the H. pylori morphogenesis showed a decrease in their expression during exposure to myricetin. This inhibitory effect was more strongly seen for genes involved in the muropeptide monomers shortening (csd3, csd6, csd4, and amiA), suggesting their significant participation in the spiral-to-coccoid transition. To our knowledge, this is the first research showing the ability of any compound to synergistically interact with all five antibiotics against H. pylori and the first one showing the capacity of a natural substance to interfere with the morphological transition of H. pylori from spiral to coccoid forms.

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Ages of Galactic and Extragalactic Star Clusters of Various Abundances

Highlights of Astronomy ◽

10.1017/s1539299600005025 ◽

1983 ◽

Vol 6 ◽

pp. 109-117 ◽

Cited By ~ 3

Author(s):

R.D. Cannon

Keyword(s):

Star Clusters ◽

Magellanic Clouds ◽

Open Clusters ◽

Simultaneous Solution ◽

Low Mass Stars ◽

Cluster Systems ◽

Distant Cluster ◽

Low Mass

In this review I shall concentrate mainly on globular star clusters in our Galaxy since these are the objects for which most work has been done recently, both observationally and theoretically. However, I shall also discuss briefly the oldest open clusters and clusters in the Magellanic Clouds. Little can be said about more distant cluster systems, since the only observations available are of integrated colours or spectra and these seem to be rather unreliable indicators of age. It is perhaps worth pointing out that the title may be slightly misleading; the problem is not so much to determine the ages of clusters of known abundances, as to obtain the best simultaneous solution for both age and composition, since some of the most important abundances (notably helium and oxygen) are virtually unobservable in little-evolved low mass stars.

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Synthesis of magnesium carbonate hydrate from natural talc

Open Chemistry ◽

10.1515/chem-2020-0154 ◽

2020 ◽

Vol 18 (1) ◽

pp. 951-961

Author(s):

Qiuju Chen ◽

Tao Hui ◽

Hongjuan Sun ◽

Tongjiang Peng ◽

Wenjin Ding

Keyword(s):

Crystal Structure ◽

Particle Size ◽

Crystal Growth ◽

Crystal Morphology ◽

Magnesium Carbonate ◽

Organic Additives ◽

X Ray Diffraction ◽

Morphological Transformation ◽

X Ray ◽

Carbonation Process

AbstractVarious morphologies of magnesium carbonate hydrate had been synthesized without using any organic additives by carefully adjusting the reaction temperature and time during the talc carbonation process. At lower temperatures, magnesium carbonate hydrate was prone to display needle-like morphology. With the further increase of the carbonation temperature, the sheet-like crystallites became the preferred morphology, and at higher aging temperatures, these crystallites tended to assemble into layer-like structures with diverse morphologies, such as rose-like particles and nest-like structure. The reaction time had no effect on the crystal morphology, but it affected the particle size and situation of the crystal growth. X-Ray diffraction results showed that these various morphologies were closely related to their crystal structure and compositions. The needle-like magnesium carbonate hydrate had a formula of MgCO3·3H2O, whereas with the morphological transformation from needle-like to sheet-like, rose-like, and nest-like structure, their corresponding compositions also changed from MgCO3·3H2O to 4MgCO3·Mg(OH)2·8H2O, 4MgCO3·Mg(OH)2·5H2O, and 4MgCO3·Mg(OH)2·4H2O.

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Transition-metal ion-mediated morphological transformation of pyridine-based peptide nanostructures

New Journal of Chemistry ◽

10.1039/d0nj04260a ◽

2021 ◽

Vol 45 (1) ◽

pp. 153-161

Author(s):

Narendra Singh ◽

Ramesh Singh ◽

Swati Sharma ◽

Khushboo Kesharwani ◽

Khashti Ballabh Joshi ◽

...

Keyword(s):

Transition Metal ◽

Metal Ion ◽

Chemical Structure ◽

Morphological Transformation ◽

Transition Metal Ion

Pyridine-mediated constitutionally isomeric artificial metallopeptides possess remarkable advantages over the natural counterparts mainly due to their tailor-made chemical structure.

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