The formation, evolution and death of massive stars release large quantities of energy and momentum into the gas surrounding the sites of star formation. This process, generically termed 'feedback', inhibits further star formation either by removing gas from the galaxy, or by heating it to temperatures that are too high to form new stars. Observations reveal feedback in the form of galactic-scale outflows of gas in galaxies with high rates of star formation, especially in the early Universe.
View Article and Find Full Text PDFAlthough grand-design spiral galaxies are relatively common in the local Universe, only one has been spectroscopically confirmed to lie at redshift z > 2 (HDFX 28; z = 2.011); and it may prove to be a major merger that simply resembles a spiral in projection. The rarity of spirals has been explained as a result of disks being dynamically 'hot' at z > 2 (refs 2-5), which may instead favour the formation of commonly observed clumpy structures.
View Article and Find Full Text PDFLower socioeconomic status and lack of access to care are often implicated as plausible causes for African American women to present with later stage breast cancer than Caucasian women. Our objective is to determine if racial differences are present in newly diagnosed breast cancer in women of equivalent socioeconomic status. A retrospective review of prospectively gathered data from women with newly diagnosed breast cancer was performed.
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