The role of black holes in galaxy formation and evolution.

Virtually all massive galaxies, including our own, host central black holes ranging in mass from millions to billions of solar masses. The growth of these black holes releases vast amounts of energy that powers quasars and other weaker active galactic nuclei. A tiny fraction of this energy, if absorbed by the host galaxy, could halt star formation by heating and ejecting ambient gas. A central question in galaxy evolution is the degree to which this process has caused the decline of star formation in large elliptical galaxies, which typically have little cold gas and few young stars, unlike spiral galaxies.

The Big Bang as scientific fact.

In the year 1900, humanity had barely a notion of our place on the cosmic stage, and no inkling at all of how we got here. The one hundred short years of the twentieth century sufficed to unravel 14 billion years of cosmic history and how those grand events, after 9 billions of years or so, set the stage for the birth of our own home, the Solar System. The key events in this history are not hard to comprehend; they can be sketched in a few brief pages. This precious knowledge is part of our shared heritage as human beings and is fundamental to the future prospects of our species. Without it, we are ignorant of the powerful forces that have shaped our past and that will shape our destiny in the future. Read here the cosmic history of humanity, beginning with the Big Bang.

Experience with Eudragit-S-coated mesalamine (Asacol) in inflammatory bowel disease. An open study.

We reviewed the courses of 63 patients with inflammatory bowel disease (IBD) treated in a private gastroenterology practice. All were allergic, unresponsive, or in some way intolerant of sulfasalazine and therefore were treated with Eudragit-S-coated mesalamine (Asacol). Thirty-eight patients had ulcerative colitis (UC) and 25 had Crohn's disease. In 22 and 14, respectively, mesalamine was used to treat active disease; in 16 and 11, respectively, it was introduced to maintain remission. In some patients, mesalamine was used along with other medications. Symptomatic and endoscopic response was seen in seven of nine (77%) with active UC treated with measalamine alone; remission was maintained in seven of eight (94%) when mesalamine was used alone. Therapeutic success was noted in eight of 10 (80%) with active Crohn's disease, and remission was maintained in seven of nine (78%) when mesalamine was used alone. Adverse reactions of varying severity occurred in 21 of 63 (33%), but the drug had to be terminated in only 9 of 63 (14%). Eudragit-S-coated mesalamine appears to be effective in the treatment and maintenance of remission of UC in 82% of those patients allergic or intolerant to the parent drug, sulfasalazine. Furthermore, contrary to what was expected, we found it effective in a much larger percentage of patients with Crohn's disease (79%) than the parent drug.