Coggon, R. M., Teagle, D. A. H., Sylvan, J. B., Reece, J., Estes, E. R., Williams, T. J., Christeson, G. L., Aizawa, M., Albers, E., Amadori, C., Belgrano, T. M., Borrelli, C., Bridges, J. D., Carter, E. J., D'Angelo, T., Dinarès-Turell, J., Doi, N., Estep, J. D., Evans, A., and Gilhooly III, W. P.
Coggon, R. M., Sylvan, J. B., Estes, E. R., Teagle, D. A. H., Reece, J., Williams, T. J., Christeson, G. L., Aizawa, M., Borrelli, C., Bridges, J. D., Carter, E. J., Dinarès-Turell, J., Estep, J. D., Gilhooly III, W. P., Grant, L. J. C., Kaplan, M. R., Kempton, P. D., Lowery, C. M., McIntyre, A., and Routledge, C. M.
Coggon, R. M., Sylvan, J. B., Estes, E. R., Teagle, D. A. H., Reece, J., Williams, T. J., Christeson, G. L., Aizawa, M., Borrelli, C., Bridges, J. D., Carter, E. J., Dinarès-Turell, J., Estep, J. D., Gilhooly III, W. P., Grant, L. J. C., Kaplan, M. R., Kempton, P. D., Lowery, C. M., McIntyre, A., and Routledge, C. M.
Coggon, R. M., Sylvan, J. B., Estes, E. R., Teagle, D. A. H., Reece, J., Williams, T. J., Christeson, G. L., Aizawa, M., Borrelli, C., Bridges, J. D., Carter, E. J., Dinarès-Turell, J., Estep, J. D., Gilhooly III, W. P., Grant, L. J. C., Kaplan, M. R., Kempton, P. D., Lowery, C. M., McIntyre, A., and Routledge, C. M.
Coggon, R. M., Teagle, D. A. H., Sylvan, J. B., Reece, J., Estes, E. R., Williams, T. J., Christeson, G. L., Aizawa, M., Albers, E., Amadori, C., Belgrano, T. M., Borrelli, C., Bridges, J. D., Carter, E. J., D'Angelo, T., Dinarès-Turell, J., Doi, N., Estep, J. D., Evans, A., and Gilhooly III, W. P.
Coggon, R. M., Teagle, D. A. H., Sylvan, J. B., Reece, J., Estes, E. R., Williams, T. J., Christeson, G. L., Aizawa, M., Albers, E., Amadori, C., Belgrano, T. M., Borrelli, C., Bridges, J. D., Carter, E. J., D'Angelo, T., Dinarès-Turell, J., Doi, N., Estep, J. D., Evans, A., and Gilhooly III, W. P.
The South Atlantic Transect (SAT) is a multidisciplinary scientific ocean drilling experiment designed to investigate the evolution of the ocean crust and overlying sediments across the western flank of the Mid-Atlantic Ridge. This project comprises four International Ocean Discovery Program expeditions: fully staffed Expeditions 390 and 393 (April-August 2022) built on engineering preparations during Expeditions 390C and 395E (October-December 2020 and April-June 2021, respectively) that took place without science parties during the height of the Coronavirus Disease 2019 (COVID-19) pandemic. Through operations along a crustal flow line at ~31°S, the SAT recovered complete sedimentary sections and the upper ~40-340 m of the underlying ocean crust formed at a slow-to intermediate-spreading rate at the Mid-Atlantic Ridge over the past ~61 My. The sediments along this transect were originally spot cored more than 50 y ago during Deep Sea Drilling Project Leg 3 (December 1968-January 1969) to help verify the theories of seafloor spreading and plate tectonics. The SAT expeditions targeted six primary sites on 7, 15, 31, 49, and 61 Ma ocean crust that fill critical gaps in our sampling of intact in situ ocean crust with regard to crustal age, spreading rate, and sediment thickness. Drilling these sites was required to investigate the history, duration, and intensity of the low-temperature hydrothermal interactions between the aging ocean crust and the evolving South Atlantic Ocean. This knowledge will improve the quantification of past hydrothermal contributions to global biogeochemical cycles and help develop a predictive understanding of the impacts of variable hydrothermal processes and exchanges. Samples from the transect of the previously unexplored sediment- and basalt-hosted deep biosphere beneath the South Atlantic Gyre are essential to refine global biomass estimates and examine microbial ecosystems' responses to variable conditions in a low-energy gyre and aging ocean crust. The transect, located near World Ocean Circulation Experiment Line A10, provides records of carbonate chemistry and deepwater mass properties across the western South Atlantic through key Cenozoic intervals of elevated atmospheric CO2 and rapid climate change. Reconstruction of the history of the deep western boundary current and deepwater formation in the Atlantic basins will yield crucial data to test hypotheses regarding the role of evolving thermohaline circulation patterns in climate change and the effects of tectonic gateways and climate on ocean acidification. During engineering Expeditions 390C and 395E (5 October-5 December 2020 and 6 April-6 June 2021, respectively), a single hole was cored through the sediment cover and into the uppermost rocks of the ocean crust with the advanced piston corer and extended core barrel systems at five of the six primary proposed SAT sites. Reentry systems with casing were then installed either into basement or within 10 m of basement at each of those five sites. Expedition 390 (7 April-7 June 2022) conducted operations at three of the SAT sites, recovering 700 m of core (77% recovery) over 30.3 days of on-site operations. Sediment coring, basement coring, and wireline logging were conducted at two sites on ~61 Ma crust (Sites U1556 and U1557), and sediment coring was completed at the 7 Ma Site U1559. During Expedition 390, more than 1.2 km of sediments was characterized, including 793 m of core collected during Expeditions 390C and 395E at Sites U1556, U1557, and U1559 as well as Expedition 395E Site U1561, which was cored on thinly (<50 m) sedimented ~61 Ma crust. The uppermost ~342 and ~120 m of ~61 Ma ocean crust was cored at Sites U1556 and U1557, respectively. Geophysical wireline logging was achieved at both sites, but the basement hole at Site U1556 was not preserved as a legacy hole because of subsidence of the reentry cone below the seafloor. At Site U1557, the drill bit was deposited on the seafloor prior to downhole logging, leaving Hole U1557D available for future deepening and establishing a legacy borehole for basement hydrothermal and microbiological experiments. Expedition 393 (7 June-7 August 2022) operated at four sites, drilling in 12 holes to complete this initial phase of the SAT. Complete sedimentary sections were collected at Sites U1558, U1583, and U1560 on 49, 31, and 15 Ma crust, respectively, and together with 257.7 m of sediments cored during earlier operations, more than 600 m of sediments was characterized. The uppermost ocean crust was drilled at Sites U1558, U1560, and U1583 with good penetration (~130 to ~204 meters subbasement); however, at the youngest ~7 Ma Site U1559, only ~43 m of basement penetration was achieved in this initial attempt. Geophysical wireline logs were achieved at Sites U1583 and U1560 only. Expeditions 390 and 393 established legacy sites available for future deepening and downhole basement hydrothermal and microbiological experiments at Sites U1557, U1560, and U1559 on 61, 15, and 7 Ma crust, respectively. Highlights of the SAT expeditions include (1) recovering abundant altered glass, hydrothermal veins, complex breccias, and a wide range of alteration halos in the volcanic sequences of the uppermost ocean crust formed at 7-61 Ma, indicating low-temperature hydrothermal processes and exchanges between seawater and basalts across the western flank of the southern Mid-Atlantic Ridge for millions to tens of millions of years; (2) documenting extended redox gradients from both the seafloor and the sediment/basement interface that indicate significant subsurface fluid flow and may support a diversity of microorganisms and metabolisms; and (3) recovering an almost complete stratigraphic record of the Cenozoic (including the Paleocene/Eocene Thermal Maximum and other key climate events) composed of nannofossil oozes with varying amounts of clay indicating the shoaling and deepening of the calcite compensation depth. [ABSTRACT FROM AUTHOR]
Borrelli, C., Katz, M. E., and Toggweiler, J. R.
Sedimentary records show that calcium carbonate (CaCO3) preservation fluctuated during the Eocene. These fluctuations are well documented for the equatorial Pacific. However, data from other basins are sparse. In this study, we report new middle and late Eocene bulk calcium carbonate percentages and accumulation rates from the northwestern Pacific (Ocean Drilling Program—ODP—Site 884) and the Atlantic (ODP Sites 1053, 1090, and 1263) Oceans; in addition, we calculate CaCO3 accumulation rates for sites with published percentage bulk CaCO3 to expand geographic and paleobathymetric coverage. Using these data, we investigate the response of the carbonate cycle to environmental changes (e.g., temperatures, primary productivity, weathering, and ocean circulation) at the beginning of the greenhouse‐icehouse transition (∼43–34 Ma). Our results show that in the middle to late Eocene CaCO3 accumulation rates were highly variable at different paleodepths and ocean basins suggesting that the evolution of carbonate accumulation rates over the Eocene was influenced by different processes in different locations. In particular, our data emphasize the role of surface CaCO3 production and ocean ventilation in driving changes in CaCO3 preservation and burial at the seafloor. Our study also highlights the need for a better understanding of the processes regulating CaCO3 surface production today in order to correctly interpret geological records. Plain Language Summary: Over geological timescales, CaCO3 production in the ocean surface and burial in marine sediments are important components of the global carbon cycle. A rapid increase in CaCO3 preservation at deeper depths occurred at the Eocene/Oligocene boundary. However, what drove this change is still debated. Here, we investigate CaCO3 accumulation at sites from different paleodepths and ocean basins during the middle and late Eocene (∼43–34 Ma). This is a particularly important period of time as it marks the beginning of the greenhouse‐to‐icehouse climate transition. Our results show that CaCO3 accumulation and dissolution were spatially and temporally heterogeneous. Based on this, we propose that CaCO3 production at the ocean surface, as well as changes in ocean circulation, had a fundamental role in driving CaCO3 preservation in different ocean basins. Key Points: Calculation and comparison of carbonate accumulation rates depend on solid age modelsGeographic and paleobathymetric carbonate accumulation rates were highly variable during the middle and late EoceneSurface carbonate production and ocean ventilation were important drivers of the middle and late Eocene carbonate accumulation rates [ABSTRACT FROM AUTHOR]
Borrelli, C., Sabbatini, A., Luna, G. M., Nardelli, M. P., Sbaffi, T., Morigi, C., Danovaro, R., and Negri, A.
Benthic foraminifera are an important component of the marine biota, but protocols for investigating their viability and metabolism are still extremely limited. Classical studies on benthic foraminifera have been based on direct counting under light microscopy. Typically, these organisms are stained with Rose Bengal, which binds proteins and other macromolecules, but does not allow discrimination between viable and recently dead organisms. The fluorescent in situ hybridization technique (FISH) represents a new and useful approach to identify living cells possessing an active metabolism. Our work is the first test of the suitability of the FISH technique, based on fluorescent probes targeting the 18S rRNA, to detect live benthic foraminifera. The protocol was applied on Ammonia group and Miliolids, as well as on agglutinated polythalamous (i.e., Leptohalysis scottii and Eggerella scabra) and soft-shelled monothalamous (i.e., Psammophaga sp. and saccamminid morphotypes) taxa. The results from FISH analyses were compared with those obtained, on the same specimens assayed with FISH, from microscopic analysis of the cytoplasm colour, presence of pigments and pseudopodial activity. Our results indicate that FISH targets only metabolically active foraminifera, and allows discerning from low to high cellular activity, validating the hypothesis that the intensity of the fluorescent signal emitted by the probe is dependent upon the physiological status of cells. These findings support the usefulness of this molecular approach as a key tool for obtaining information on the physiology of living foraminifera, both in field and experimental settings. [ABSTRACT FROM AUTHOR]
Borrelli, C., Sabbatini, A., Luna, G. M., Morigi, C., Danovaro, R., and Negri, A.
Benthic foraminifera are an important component of the marine living biota, but protocols for investigating their viability and metabolism are still extremely limited. Classical studies on benthic foraminifera have been based on direct counting under light microscopy.Typically these organisms are stained with Rose Bengal, which binds proteins and other macromolecules, but this approach does not allow discriminating between viable and recently dead organisms. The fluorescent in situ hybridization technique (FISH) represents a potentially useful approach identifying living cells with active metabolism cells. In this work, we tested for the first time the suitability of the FISH technique based on fluorescent probes targeting the 18S rRNA, to detect these live benthic protists. The protocol was applied on the genus Ammonia, on the Miliolidae group and an attempt was made also with agglutinated species (i.e., Leptohalysis scottii and Eggerella scabra). In addition microscopic analysis of the cytoplasm colour, presence of pigments and, sometimes, those of pseudopodial activity where conducted. The results of the present study indicate that FISH targeted only live and metabolically active foraminifera. These results allowed to identify as "live", cells improperly classified as "dead" by means of the classical technique (Type I error) and vice versa to identify as dead the foraminifera without rRNA, but stained using Rose Bengal (Type II error). In addition, the comparative FISH analysis of starved and actively growing cells demonstrated that individuals with active metabolism were stained more intensively than starved cells. This finding supports the hypothesis that the physiological status of cells can be directly related with the intensity of the fluorescent signal emitted by the fluorescent probe. We conclude that the use of molecular approaches could represent a key tool for acquiring crucial information on living foraminifera speci mens and for investigating their ecological role in marine sediments. [ABSTRACT FROM AUTHOR]
Gori, E., Arpinati, M., Bonifazi, F., Errico, A., Mega, A., Alberani, F., Sabbi, V., Costazza, G., Leanza, S., Borrelli, C., Berni, M., Feraut, C., Polato, E., Altieri, M. C., Pirola, E., Loddo, M. C., Banfi, M., Barzetti, L., Calza, S., and Brignoli, C.
Severe oral mucositis is a major cause of morbidity following allogeneic hematopoietic stem cell transplantation (AHSCT). Cryotherapy, that is, the application of ice chips on the mucosa of the oral cavity during the administration of antineoplastic agents, may reduce the incidence and severity of chemotherapy-related oral mucositis. In this multicenter randomized study, we addressed whether cryotherapy during MTX administration is effective in the prevention of severe oral mucositis in patients undergoing myeloablative AHSCT. One hundred and thirty patients undergoing myeloablative AHSCT and MTX-containing GVHD prophylaxis were enrolled and randomized to receive or not receive cryotherapy during MTX administration. The incidence of severe (grade 3–4) oral mucositis, the primary end point of the study, was comparable in patients receiving or not cryotherapy. Moreover, no difference was observed in the incidence of oral mucositis grade 2–4 and the duration of oral mucositis grade 3–4 or 2–4, or in the kinetics of mucositis over time. In univariate and multivariate analysis, severe oral mucositis correlated with TBI in the conditioning regimen and lack of folinic acid rescue following MTX administration. Thus, cryotherapy during MTX administration does not reduce severe oral mucositis in patients undergoing myeloablative allogeneic HSCT. Future studies will assess cryotherapy before allogeneic HSCT.Bone Marrow Transplantation (2007) 39, 347–352. doi:10.1038/sj.bmt.1705590; published online 5 February 2007 [ABSTRACT FROM AUTHOR]
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