Islands of ice: Influence of free-drifting Antarctic icebergs on pelagic marine ecosystems

Regional warming around West Antarctica, including the Antarctic Peninsula, is related to the retreat of glaciers that has resulted in significant ice mass loss in recent decades. We examined freedrifting icebergs in the Atlantic sector of the Southern Ocean in December 2005, aboard ARSV Laurence M. Gould, and in June 2008 and March/April 2009, aboard RVIB Nathaniel B. Palmer. Prior to these studies, little information was available about the effects of icebergs on the pelagic realm.Facultad de Ciencias Naturales y Muse

Islands of ice: Influence of free-drifting Antarctic icebergs on pelagic marine ecosystems

Regional warming around West Antarctica, including the Antarctic Peninsula, is related to the retreat of glaciers that has resulted in significant ice mass loss in recent decades. We examined freedrifting icebergs in the Atlantic sector of the Southern Ocean in December 2005, aboard ARSV Laurence M. Gould, and in June 2008 and March/April 2009, aboard RVIB Nathaniel B. Palmer. Prior to these studies, little information was available about the effects of icebergs on the pelagic realm.Facultad de Ciencias Naturales y Muse

Ice sheets as a missing source of silica to the polar oceans

Ice sheets play a more important role in the global silicon cycle than previously appreciated. Input of dissolved and amorphous particulate silica into natural waters stimulates the growth of diatoms. Here we measure dissolved and amorphous silica in Greenland Ice Sheet meltwaters and icebergs, demonstrating the potential for high ice sheet export. Our dissolved and amorphous silica flux is 0.20 (0.06-0.79) Tmol year(-1), ∼50% of the input from Arctic rivers. Amorphous silica comprises >95% of this flux and is highly soluble in sea water, as indicated by a significant increase in dissolved silica across a fjord salinity gradient. Retreating palaeo ice sheets were therefore likely responsible for high dissolved and amorphous silica fluxes into the ocean during the last deglaciation, reaching values of ∼5.5 Tmol year(-1), similar to the estimated export from palaeo rivers. These elevated silica fluxes may explain high diatom productivity observed during the last glacial-interglacial period

Frozen elephant trunk surgery using the E-vita open plus prosthesis.

this manuscript describes our surgical FET approach with ASCP in detail. The video illustrates the surgical treatment of a 75-year-old man who had previously undergone a Bentall procedure and myocardial revascularization for a DeBakey type 1 acute aortic dissection

'Double layer' frozen elephant trunk with balloon endoclamping: A technique to simplify the 2-stage open repair of thoraco-abdominal aortic aneurysms

Staged replacement of the aortic arch and thoraco-abdominal aorta (TAA) with a frozen elephant trunk followed by TAA repair is a valuable treatment for patients with chronic TAA dissection. However, in patients with an unclampable descending thoracic aorta, the retrieval of the trunk can be problematic and the proximal stent graft-to-graft anastomosis technically challenging. Here we present our 'double layer' frozen elephant trunk technique to treat patients with TAA dissection

Aortic root endocarditis: A Biointegral Bioconduit subannular implantation

none4no-noneEusanio M.D.; Berretta P.; Alfonsi J.; Cefarelli M.Eusanio M.D.; Berretta P.; Alfonsi J.; Cefarelli M