84 resultados para Orbital volume
Resumo:
In North America, terrestrial records of biodiversity and climate change that span Marine Oxygen Isotope Stage (MIS) 5 are rare. Where found, they provide insight into how the coupling of the ocean-atmosphere system is manifested in biotic and environmental records and how the biosphere responds to climate change. In 2010-2011, construction at Ziegler Reservoir near Snowmass Village, Colorado (USA) revealed a nearly continuous, lacustrine/wetland sedimentary sequence that preserved evidence of past plant communities between similar to 140 and 55 lea, including all of MIS 5. At an elevation of 2705 m, the Ziegler Reservoir fossil site also contained thousands of well-preserved bones of late Pleistocene megafauna, including mastodons, mammoths, ground sloths, horses, camels, deer, bison, black bear, coyotes, and bighorn sheep. In addition, the site contained more than 26,000 bones from at least 30 species of small animals including salamanders, otters, muskrats, minks, rabbits, beavers, frogs, lizards, snakes, fish, and birds. The combination of macro- and micro-vertebrates, invertebrates, terrestrial and aquatic plant macrofossils, a detailed pollen record, and a robust, directly dated stratigraphic framework shows that high-elevation ecosystems in the Rocky Mountains of Colorado are climatically sensitive and varied dramatically throughout MIS 5
Resumo:
Using patch-clamp and calcium imaging techniques, we characterized the effects of ATP and histamine on human keratinocytes. In the HaCaT cell line, both receptor agonists induced a transient elevation of [Ca2+]i in a Ca2+-free medium followed by a secondary [Ca2+]i rise upon Ca2+ readmission due to store-operated calcium entry (SOCE). In voltage-clamped cells, agonists activated two kinetically distinct currents, which showed differing voltage dependences and were identified as Ca2+-activated (ICl(Ca)) and volume-regulated (ICl, swell) chloride currents. NPPB and DIDS more efficiently inhibited ICl(Ca) and ICl, swell, respectively. Cell swelling caused by hypotonic solution invariably activated ICl, swell while regulatory volume decrease occurred in intact cells, as was found in flow cytometry experiments. The PLC inhibitor U-73122 blocked both agonist- and cell swelling–induced ICl, swell, while its inactive analogue U-73343 had no effect. ICl(Ca) could be activated by cytoplasmic calcium increase due to thapsigargin (TG)-induced SOCE as well as by buffering [Ca2+]i in the pipette solution at 500 nM. In contrast, ICl, swell could be directly activated by 1-oleoyl-2-acetyl-sn-glycerol (OAG), a cell-permeable DAG analogue, but neither by InsP3 infusion nor by the cytoplasmic calcium increase. PKC also had no role in its regulation. Agonists, OAG, and cell swelling induced ICl, swell in a nonadditive manner, suggesting their convergence on a common pathway. ICl, swell and ICl(Ca) showed only a limited overlap (i.e., simultaneous activation), although various maneuvers were able to induce these currents sequentially in the same cell. TG-induced SOCE strongly potentiated ICl(Ca), but abolished ICl, swell, thereby providing a clue for this paradox. Thus, we have established for the first time using a keratinocyte model that ICl, swell can be physiologically activated under isotonic conditions by receptors coupled to the phosphoinositide pathway. These results also suggest a novel function for SOCE, which can operate as a "selection" switch between closely localized channels.
Resumo:
This study presents a reproducible, cost-effective in vitro encrustation model and, furthermore, describes the effects of components of the artificial urine and the presence of agents that modify the action of urease on encrustation on commercially available ureteral stents. The encrustation model involved the use of small-volume reactors (700 mL) containing artificial urine and employing an orbital incubator (at 37 degrees C) to ensure controlled stirring. The artificial urine contained sources of calcium and magnesium (both as chlorides), albumin and urease. Alteration of the ratio (% w/w) of calcium salt to magnesium salt affected the mass of encrustation, with the greatest encrustation noted whenever magnesium was excluded from the artificial urine. Increasing the concentration of albumin, designed to mimic the presence of protein in urine, significantly decreased the mass of both calcium and magnesium encrustation until a plateau was observed. Finally, exclusion of urease from the artificial urine significantly reduced encrustation due to the indirect effects of this enzyme on pH. Inclusion of the urease inhibitor, acetohydroxamic acid, or urease substrates (methylurea or ethylurea) into the artificial medium markedly reduced encrustation on ureteral stents. In conclusion, this study has described the design of a reproducible, cost-effective in vitro encrustation model. Encrustation was markedly reduced on biomaterials by the inclusion of agents that modify the action of urease. These agents may, therefore, offer a novel clinical approach to the control of encrustation on urological medical devices. (c) 2005 Wiley Periodicals, Inc.
Resumo:
Volume III of the new eleven-volume edition of Milton's Complete Works provides a definitive scholarly edition of all of Milton's shorter poems in English, Latin, Italian, and Greek, as well as his Mask, taken from both published and manuscript sources. It includes his 1645 Poems complete with all prefatory materials, thus illuminating the ways in which author, publisher, and print shop shaped this volume. It then presents all the new poems added in the 1673 edition (with the new Table of Contents), as well as the poems omitted from both editions. A careful collation of textual variants among these sources as well as the 1637 anonymous publication of Milton's Mask is provided. The Bridgewater manuscript of Milton's Mask (probably close to the acting version) and his working copy from the Trinity Manuscript, with its many alterations and additions, are transcribed in their entirety, so that the various versions may be compared and studied.
A special feature of this edition is a new translation of Milton's many Latin and Greek poems that is both accurate and attentive to their literary qualities. This is augmented by a detailed and comprehensive commentary that highlights classical, vernacular, and neo-Latin parallels. A poetic translation of Milton's six Italian sonnets and Canzone is also supplied. In addition, the Appendices contain all the versions of Milton's shorter poems in all the contemporary manuscript and printed sources, so they may be examined in relation to their specific contexts. The transcription of all the versions of Milton's poems in the Trinity Manuscript allows in several cases, notably 'Lycidas' and 'At a Solemn Music,' for examination of the evolution of these poems as Milton weighed choiced of diction and sound qualities, enabling further understanding of his poetic practices.
Barbara Lewalski is responsible for text, textual apparatus, and commentary pertaining to the vernacular poems in all sections of this edition including the appendices, and manuscript transcriptions (with the exception of A Maske), as well as the Occasions, Vernacular Poems,and Textual Introductions. Estelle Haan is responsible for text, textual apparatus, and commentary for the Poemata in all sections of this edition,and for the Poemata Introduction. She has also provided all translations from Latin, Italian, and Greek in the Testimonia, Poemata, and associated commentary, and transcriptions of the BL Damon, the Bodleian AdJoannem Rousium, and A Maske from the Trinity and Bridgewater manuscripts. Andrew McNeillie has provided poetic translations for Milton’s Italian sonnets, and Jason Rosenblatt has provided some Hebrew text and commentary pertaining to Milton’s Psalm translations.John Cunningham has transcribed Henry Lawes’ music for Milton’s masque, with commentary (Appendix E). Biblical references are taken from the King James (Authorized) Version.