4 research outputs found
Variations in the 6.2 m emission profile in starburst-dominated galaxies: a signature of polycyclic aromatic nitrogen heterocycles (PANHs)?
Analyses of the polycyclic aromatic hydrocarbon (PAH) feature profiles,
especially the 6.2 m feature, could indicate the presence of nitrogen
incorporated in their aromatic rings. In this work, 155 predominantly
starburst-dominated galaxies (including HII regions and Seyferts, for example),
extracted from the Spitzer/IRS ATLAS project (Hern\'an-Caballero &
Hatziminaoglou 2011), have their 6.2 m profiles fitted allowing their
separation into the Peeters' A, B and C classes (Peeters et al. 2002). 67% of
these galaxies were classified as class A, 31% were as class B and 2% as class
C. Currently class A sources, corresponding to a central wavelength near 6.22
m, seem only to be explained by polycyclic aromatic nitrogen heterocycles
(PANH, Hudgins et al. 2005), whereas class B may represent a mix between PAHs
and PANHs emissions or different PANH structures or ionization states.
Therefore, these spectra suggest a significant presence of PANHs in the
interstellar medium (ISM) of these galaxies that could be related to their
starburst-dominated emission. These results also suggest that PANHs constitute
another reservoir of nitrogen in the Universe, in addition to the nitrogen in
the gas phase and ices of the ISM
Comment on "Ab initio calculations of the lattice parameter and elastic stiffness coefficients of bcc Fe with solutes" Comp. Mat. Sci. v.126 pp.503-513 (2017)
In a recent paper, the authors propose to separately calculate the volumetric
and chemical contributions to the elastic stiffness coefficients of systems
containing solutes, as it is "computationally more efficient". We show that
this is not the case and further that their methodology and hence their results
are incorrect. There is no short cut for performing the desired calculations,
if done rigorously, as we show in our 2012 work
Application of <i>Spiroplasma melliferum</i> Proteogenomic Profiling for the Discovery of Virulence Factors and Pathogenicity Mechanisms in Host-associated Spiroplasmas
To date, no genome of any of the species from the genus <i>Spiroplasma</i> has been completely sequenced. Long repetitive
sequences similar to mobile units present a major obstacle for current
genome sequencing technologies. Here, we report the assembly of the <i>Spiroplasma melliferum</i> KC3 genome into 4 contigs, followed
by proteogenomic annotation and metabolic reconstruction based on
the discovery of 521 expressed proteins and comprehensive metabolomic
profiling. A systems approach allowed us to elucidate putative pathogenicity
mechanisms and to discover major virulence factors, such as Chitinase
utilization enzymes and toxins never before reported for insect pathogenic
spiroplasmas
Additional file 5: of Genome analysis of E. coli isolated from Crohn’s disease patients
Phage sensitivity test of E. coli CD-isolates (see Methods). (DOC 45 kb