8 research outputs found
Globular cluster systems and galaxy formation
Globular clusters are compact, gravitationally bound systems of up to a
million stars. The GCs in the Milky Way contain some of the oldest stars known,
and provide important clues to the early formation and continuing evolution of
our Galaxy. More generally, GCs are associated with galaxies of all types and
masses, from low-mass dwarf galaxies to the most massive early-type galaxies
which lie in the centres of massive galaxy clusters. GC systems show several
properties which connect tightly with properties of their host galaxies. For
example, the total mass of GCs in a system scales linearly with the dark matter
halo mass of its host galaxy. Numerical simulations are at the point of being
able to resolve globular cluster formation within a cosmological framework.
Therefore, GCs link a range of scales, from the physics of star formation in
turbulent gas clouds, to the large-scale properties of galaxies and their dark
matter. In this Chapter we review some of the basic observational approaches
for GC systems, some of their key observational properties, and describe how
GCs provide important clues to the formation of their parent galaxies.Comment: 32 pages, 6 figures. Accepted for publication in the book "Reviews in
Frontiers of Modern Astrophysics: From Space Debris to Cosmology" (eds
Kabath, Jones and Skarka; publisher Springer Nature) funded by the European
Union Erasmus+ Strategic Partnership grant "Per Aspera Ad Astra Simul"
2017-1-CZ01-KA203-03556
Proteomic Analysis of the Cyst Stage of Entamoeba histolytica
We used tandem mass spectrometry to identify E. histolytica cyst proteins in 5 cyst positive stool samples. We report the identification of 417 non-redundant E. histolytica proteins including 195 proteins that were not identified in existing trophozoite derived proteome or EST datasets, consistent with cyst specificity. Because the cysts were derived directly from patient samples with incomplete purification, a limited number of proteins were identified (Nâ=â417) that probably represent only a partial proteome. Nevertheless, the study succeeded in identifying proteins that are likely to be abundant in the cyst stage of the parasite. Several of these proteins may play roles in E. histolytica stage conversion or cyst function. Proteins identified in this study may be useful markers for diagnostic detection of E. histolytica cysts. Overall, the data generated in this study promises to aid the understanding of the cyst stage of the parasite which is vital for disease transmission and pathogenesis in E. histolytica
Dark Matter in the Milky Way's Dwarf Spheroidal Satellites
The Milky Way's dwarf spheroidal satellites include the nearest, smallest and
least luminous galaxies known. They also exhibit the largest discrepancies
between dynamical and luminous masses. This article reviews the development of
empirical constraints on the structure and kinematics of dSph stellar
populations and discusses how this phenomenology translates into constraints on
the amount and distribution of dark matter within dSphs. Some implications for
cosmology and the particle nature of dark matter are discussed, and some
topics/questions for future study are identified.Comment: A version with full-resolution figures is available at
http://www.cfa.harvard.edu/~mwalker/mwdsph_review.pdf; 70 pages, 22 figures;
invited review article to be published in Vol. 5 of the book "Planets, Stars,
and Stellar Systems", published by Springe