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127 results on '"Onofrio, R"'

1. Evolution of interface singularities in shallow water equations with variable bottom topography

Author

Camassa, R., D'Onofrio, R., Falqui, G., Ortenzi, G., and Pedroni, M.

Subjects
Mathematical Physics, Nonlinear Sciences - Exactly Solvable and Integrable Systems, Physics - Fluid Dynamics
Abstract

Wave front propagation with non-trivial bottom topography is studied within the formalism of hyperbolic long wave models. Evolution of non-smooth initial data is examined, and in particular the splitting of singular points and their short time behaviour is described. In the opposite limit of longer times, the local analysis of wavefronts is used to estimate the gradient catastrophe formation and how this is influenced by the topography. The limiting cases when the free surface intersects the bottom boundary, belonging to the so-called "physical" and "non-physical" vacuum classes, are examined. Solutions expressed by power series in the spatial variable lead to a hierarchy of ordinary differential equations for the time-dependent series coefficients, which are shown to reveal basic differences between the two vacuum cases: for non-physical vacuums, the equations of the hierarchy are recursive and linear past the first two pairs, while for physical vacuums the hierarchy is non-recursive, fully coupled and nonlinear. The former case may admit solutions that are free of singularities for nonzero time intervals, while the latter is shown to develop non-standard velocity shocks instantaneously. We show that truncation to finite dimensional systems and polynomial solutions is in general only possible for the case of a quadratic bottom profile. In this case the system's evolution can reduce to, and is completely described by, a low dimensional dynamical system for the time-dependent coefficients. This system encapsulates all the nonlinear properties of the solution for general power series initial data, and in particular governs the loss of regularity in finite times at the dry point. For the special case of parabolic bottom topographies, an exact, self-similar solution class is introduced and studied to illustrate via closed form expressions the general results., Comment: 32 pages, 15 figures

Published
2022

3. Efficient computation of collisional $\ell$-mixing rate coefficients in astrophysical plasmas

Author

Vrinceanu, D., Onofrio, R., Oonk, J. B. R., Salas, P., and Sadeghpour, H. R.

Subjects
Astrophysics - Instrumentation and Methods for Astrophysics, Astrophysics - Astrophysics of Galaxies
Abstract

We present analytical expressions for direct evaluation of $\ell$-mixing rate coefficients in proton-excited hydrogen atom collisions and describe a software package for efficient numerical evaluation of the collisional rate coefficients. Comparisons between rate coefficients calculated with various levels of approximation are discussed, highlighting their range of validity. These rate coefficients are benchmarked via radio recombination lines for hydrogen, evaluating the corresponding departure coefficients from local thermal equilibrium.

Published
2019
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4. On the treatment of $\ell$-changing proton-hydrogen Rydberg atom collisions

Author

Vrinceanu, D., Onofrio, R., and Sadeghpour, H. R.

Subjects
Physics - Atomic Physics, Astrophysics - Cosmology and Nongalactic Astrophysics
Abstract

Energy-conserving, angular momentum-changing collisions between protons and highly excited Rydberg hydrogen atoms are important for precise understanding of atomic recombination at the photon decoupling era, and the elemental abundance after primordial nucleosynthesis. Early approaches to $\ell$-changing collisions used perturbation theory for only dipole-allowed ($\Delta \ell=\pm 1$) transitions. An exact non-perturbative quantum mechanical treatment is possible, but it comes at computational cost for highly excited Rydberg states. In this note we show how to obtain a semi-classical limit that is accurate and simple, and develop further physical insights afforded by the non-perturbative quantum mechanical treatment.

Published
2017
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5. External and internal motor load in Italian young beach soccer players: A pilot study.

Author

SANNICANDRO I., COFANO G., CASTRO F., D'ONOFRIO R., and ALIBERTI S.

Abstract

Purpose. The primary aim of this study was to asses the internal and external match demands of young beach soccer players during an official match. The secondary aim was to evaluate how these demands compared to those of 11-a-side soccer Materials and methods. The study involved 24 young soccer players under the age of 17 (all outfield players). Performance assessments were performed on a sand field (35 x 28 m) with beach soccer ball, over three 12-min periods. Internal physiological indicators (heart rate, RPE) and external indicators (total distance, distance/per minute, peak speed, ecc) were collected during and after the match. Results. The internal load values obtained show that the beach soccer competition imposes high cardio-vascular intensity on the young soccer player: about 70% of the distance covered results in a HR value between 80% and 100% of HRmax, with an average HR of about 95% of HRmax. The playing time for each player was 17.11±4.23 minutes. The total distance covered and the distance achieved per minute of play were 1733.21±280.76 meters and 83.95±6.29 meters, respectively. The equivalent distance was 1957.98±320.29 meters. The peak speed reached by the young soccer players was 20.01±0.97 km/h while the average speed observed was 5.12±0.52 km/h. The distance measured in moderate- and high-intensity running was significantly lower than the value of low-intensity running (p<0.05). The metabolic power intervals showed that the young soccer players ran 1480.46 ± 236.48 meters at low power, 199.45 ± 49.56 meters at high power, 46.13 ± 14.25 at very high power, and 7.43 ± 6.57 meters at maximum power. The values at high power (p<0.05), very high power (p<0.05) and maximum power (p<0.001) were significantly lower than those at low power. Conclusions. The performance profile of the young beach soccer player imposes high heart rate values and modest mechanical load during official competition. The performance profile is very different from that of the young 11-a-side soccer player. Beach soccer can be considered a sport that complements the physical condition of the 11-a-side soccer player. [ABSTRACT FROM AUTHOR]

Published
2024
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6. SROI Methods for Impact Assessment in Economy of Wellbeing

Author

Lettieri, E., Biasin, C., Selva, A., Isella, L., Onofrio, R., Bertelè, P., Bartezzaghi, Emilio, Series Editor, Bracchi, Giampio, Series Editor, Del Bo, Adalberto, Series Editor, Sagarra Trias, Ferran, Series Editor, Stellacci, Francesco, Series Editor, Zio, Enrico, Series Editor, Andreoni, Giuseppe, editor, and Mambretti, Cinzia, editor

Published
2021
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8. Conceptual Understanding of Newtonian Mechanics through Cluster Analysis of FCI Student Answers

Author

Fazio, Claudio and Battaglia, Onofrio R.

Abstract

The Force Concept Inventory is a multiple-choice test and is one of the most popular and most analyzed concept inventories. It is used to investigate student understanding of Newtonian mechanics. A structured approach to data analysis can transform it in a "diagnostic" instrument that can validate inferences about student thinking. In this paper, we show how cluster analysis methods can be used to investigate patterns of student conceptual understanding and supply useful details about the relationships among student concepts and misconceptions. The answers given to the FCI questionnaire by a sample of freshman engineering have been analyzed. The analysis takes into account the decomposition of the force concept into the conceptual dimensions suggested by the FCI authors and successive studies. Our approach identifies latent structures within the student response patterns and groups students characterized by similar correct answers, as well as by non-correct answers. These response patterns give us new insights into the relationships between the student force concepts and their ability to analyze motions. Our results show that cluster analysis proved to be a useful tool to identify latent structures within the student conceptual understanding. Such structures can supply diagnostic insights for classroom pedagogy and teaching approaches.

Published
2019
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9. T.04.8: IBD PATIENTS SHOW WORRYING LEVELS OF SELF-REPORTED PHYSICAL INACTIVITY AS MEASURED BY THE INTERNATIONAL PHYSICAL ACTIVITY QUESTIONNAIRE INDEPENDENTLY OF DISEASE ACTIVITY AND IBD PHENOTYPE: RESULTS FROM THE EXTENDED “BE-FIT-IBD” CROSS-SECTIONAL STUDY

Author

Gravina, A.G., primary, Pellegrino, R., additional, Palladino, G., additional, Imperio, G., additional, D'Onofrio, R., additional, Arboretto, G., additional, Romeo, M., additional, Ciamarra, P., additional, Dallio, M., additional, and Federico, A., additional

Published
2024
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10. Singularities in fluid dynamics: from the classical approach to Monge-Ampère geometry

Author

D'Onofrio, R, WEIGEL, THOMAS STEFAN, D'ONOFRIO, ROBERTO, D'Onofrio, R, WEIGEL, THOMAS STEFAN, and D'ONOFRIO, ROBERTO

Abstract

This thesis presents some recently published results regarding two classical models of fluid dynamics: the 1D shallow water equations (SWE) and the 3D incompressible semigeostrophic equations., This thesis presents some recently published results regarding two classical models of fluid dynamics: the 1D shallow water equations (SWE) and the 3D incompressible semigeostrophic equations.

Published
2024

11. Extreme Planktic Foraminiferal Dwarfism Across the ETM2 in the Tethys Realm in Response to Warming.

Author

D'Onofrio, R., Barrett, R., Schmidt, D. N., Fornaciari, E., Giusberti, L., Frijia, G., Adatte, T., Sabatino, N., Monsuru, A., Brombin, V., and Luciani, V.

Subjects
DWARFISM, SUBMARINE volcanoes, OCEAN temperature, NANNOFOSSILS, GLOBAL warming, RUBIDIUM
Abstract

Pronounced warming negatively impacts ecosystem resilience in modern oceans. To offer a long‐term geological perspective of the calcareous plankton response to global warming, we present an integrated record, from two Tethyan sections (northeastern Italy), of the planktic foraminiferal and calcareous nannofossil response to the Eocene Thermal Maximum 2 hyperthermal (ETM2, ∼54 Ma). Our study reveals pronounced changes in assemblage composition and a striking dwarfing of planktic foraminiferal tests of up to 40% during the event, impacting both surface and deeper dwellers. The increased abundance of small placoliths among calcareous nannofossils is interpreted as community size reduction. Literature and our foraminiferal size data from Sites 1263 and 1209 (Atlantic and Pacific Oceans) highlights that the pronounced dwarfism is restricted to the Tethyan area. The ETM2 is characterized by warm sea surface temperatures as indicated by our δ18O data, but this warming is of global extent and cannot explain the unique dwarfism. Excluding evolutionary modifications, other potential drivers of dwarfism (eutrophication, deoxygenation, metabolic adaptation) cannot explain the exceptional dwarfism by themselves. The smallest sizes are in close temporal association with peaks in volcanic derived Hg/Th‐Hg/Rb recorded just before and at the ETM2 which could not have been brought into our sections through weathering. In contrast, size reductions are absent below and above the ETM2 at Hg peaks where δ18O data do not show warm conditions. We speculate that the local input of toxic metals from submarine volcanic emissions could have acted synergistically to warming, causing the unique dwarfism. Key Points: Calcareous plankton size in the Tethys during the Eocene Thermal Maximum 2 (ETM2) reveals marked dwarfismPronounced dwarfism was restricted to the Tethyan area, highlighting the importance of local signals in interpreting hyperthermalsCalcareous plankton were highly unstable across the ETM2 but ultimately resilient [ABSTRACT FROM AUTHOR]

Published
2024
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12. P1101 Patient-reported physical activity of IBD patients is of concern when weighed with the international physical activity questionnaire regardless of disease activity and IBD phenotype: barriers and facilitators emerged from the extended "BE-FIT-IBD" cross-sectional study

Author

Gravina, A G, primary, Pellegrino, R, additional, Palladino, G, additional, Imperio, G, additional, D'Onofrio, R, additional, Arboretto, G, additional, Romeo, M, additional, Ciamarra, P, additional, Dallio, M, additional, and Federico, A, additional

Published
2024
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17. Evolution of interface singularities in shallow water equations with variable bottom topography

Author

Camassa, R, D'Onofrio, R, Falqui, G, Ortenzi, G, Pedroni, M, Camassa R., D'Onofrio R., Falqui G., Ortenzi G., Pedroni M., Camassa, R, D'Onofrio, R, Falqui, G, Ortenzi, G, Pedroni, M, Camassa R., D'Onofrio R., Falqui G., Ortenzi G., and Pedroni M.

Abstract

Wave front propagation with nontrivial bottom topography is studied within the formalism of hyperbolic long wave models. Evolution of nonsmooth initial data is examined, and, in particular, the splitting of singular points and their short time behavior is described. In the opposite limit of longer times, the local analysis of wave fronts is used to estimate the gradient catastrophe formation and how this is influenced by the topography. The limiting cases when the free surface intersects the bottom boundary, belonging to the so-called “physical” and “nonphysical” vacuum classes, are examined. Solutions expressed by power series in the spatial variable lead to a hierarchy of ordinary differential equations for the time-dependent series coefficients, which are shown to reveal basic differences between the two vacuum cases: for nonphysical vacuums, the equations of the hierarchy are recursive and linear past the first two pairs, whereas for physical vacuums, the hierarchy is nonrecursive, fully coupled, and nonlinear. The former case may admit solutions that are free of singularities for nonzero time intervals, whereas the latter is shown to develop nonstandard velocity shocks instantaneously. Polynomial bottom topographies simplify the hierarchy, as they contribute only a finite number of inhomogeneous forcing terms to the equations in the recursion relations. However, we show that truncation to finite-dimensional systems and polynomial solutions is in general only possible for the case of a quadratic bottom profile. In this case, the system's evolution can reduce to, and is completely described by, a low-dimensional dynamical system for the time-dependent coefficients. This system encapsulates all the nonlinear properties of the solution for general power series initial data, and, in particular, governs the loss of regularity in finite times at the dry point. For the special case of parabolic bottom topographies, an exact, self-similar solution class is introduced an

Published
2022

20. Solutions and singularities of the semigeostrophic equations via the geometry of Lagrangian submanifolds

Author

D’Onofrio, R, Ortenzi, G, Roulstone, I, Rubtsov, V, D’Onofrio, Roberto, Ortenzi, Giovanni, Roulstone, Ian, Rubtsov, Volodya, D’Onofrio, R, Ortenzi, G, Roulstone, I, Rubtsov, V, D’Onofrio, Roberto, Ortenzi, Giovanni, Roulstone, Ian, and Rubtsov, Volodya

Abstract

By using Monge-Ampère geometry, we study the singular structure of a class of nonlinear Monge-Ampère equations in three dimensions, arising in geophysical fluid dynamics. We extend seminal earlier work on Monge-Ampère geometry by examining the role of an induced metric on Lagrangian submanifolds of the cotangent bundle. In particular, we show that the signature of the metric serves as a classification of the Monge-Ampère equation, while singularities and elliptic-hyperbolic transitions are revealed by degeneracies of the metric. The theory is illustrated by application to an example solution of the semigeostrophic equations.

Published
2023

22. La ricostruzione del Centro Italia: la necessità di un approccio paesaggistico per Arquata del Tronto

Author

Camaioni, C. and D'Onofrio, R.

Subjects
Urban Studies, Sociology and Political Science
Abstract

I terremoti intervengono all'improvviso e violentemente sul paesaggio. In questo articolo si sostiene la tesi che facendo leva sulla identita e sulla memoria collettiva si possano selezionare gli elementi di permanenza e di stabilita del paesaggio che potranno guidare la ricostruzione, favorendo una responsabile sperimentazione progettuale. Il Documento Direttore della Ricostruzione di Arquata del Tronto ha provato a riflettere su questi temi, suggerendo un possibile percorso progettuale.

Published
2021

26. Impact of the Middle Eocene Climatic Optimum (MECO) on Foraminiferal and Calcareous Nannofossil Assemblages in the Neo-Tethyan Baskil Section (Eastern Turkey): Paleoenvironmental and Paleoclimatic Reconstructions

Author

D'Onofrio R.[1], Zaky A.S.[2, Frontalini F.[4], Luciani V.[1], Catanzariti R.[5], Francescangeli F.[6], Giorgioni M.[7], Coccioni R.[4], Özcan E.[8], and Jovane L.[9]

Subjects
calcareous nannofossils, Technology, biota resilience, QH301-705.5, QC1-999, Holocene climatic optimum, benthic foraminifera, middle eocene climatic optimum, Neo-Tethys, Foraminifera, Paleontology, chemistry.chemical_compound, 550 Earth sciences & geology, General Materials Science, Water cycle, Biology (General), Instrumentation, QD1-999, Fluid Flow and Transfer Processes, δ13C, biology, Process Chemistry and Technology, Physics, General Engineering, Biota, planktic foraminifera, biology.organism_classification, Engineering (General). Civil engineering (General), Seafloor spreading, Computer Science Applications, Chemistry, chemistry, Benthic zone, Carbonate, TA1-2040, warming event analogues, Geology, OCEANOGRAFIA
Abstract

The Middle Eocene Climatic Optimum (MECO; ~40 Ma), which interrupted for ~500–600 kyr the long-term cooling trend culminating at the Eocene/Oligocene boundary, still requires a comprehensive understanding of the biotic resilience. Here we present a high-resolution integrated foraminiferal and calcareous nannofossil study across the MECO from the expanded and continuous Tethyan Baskil section (eastern Turkey) that offers a complete magneto-biostratigraphic and geochemical framework. The five MECO phases identified reveal a transition from oligotrophic (pre-MECO) to eu-mesotrophic conditions, possibly related to accelerated hydrological cycle, during the initial MECO and MECO δ13C negative excursion phases. The MECO WARMING PEAK phase, marking the highest carbonate dissolution interval, records the most striking biotic changes, such as peak in warm and eutrophic nannofossils, virtual disappearance of the oligotrophic planktic foraminiferal large Acarinina and Morozovelloides, and peak in eutrophic deep dwellers Subbotina. Benthic foraminifera suggest in this phase an improvement in the quality of organic matter to the seafloor. The post-MECO phase shows only a partial recovery of the pre-event conditions. Large Acarinina and Morozovelloides did not recover their abundance, possibly due to cooler conditions in this phase. Our reconstruction reveals how paleoenvironment and marine biota from the studied Neo-Tethyan setting reacted to the MECO perturbations.

Published
2021

28. P559 Efficacy of Ustekinumab in the treatment of patients with Crohn’s disease with failure to previous conventional or biologic therapy: an observational real-life study

Author

Miranda, A, primary, Cuomo, A, additional, Camera, S, additional, Ciacci, C, additional, De Filippo, F R, additional, Gravina, A G, additional, D’Onofrio, V, additional, Melina, R, additional, Manguso, F, additional, Priadko, K, additional, Facchiano, A, additional, Bennato, R, additional, D’Onofrio, R, additional, Cuomo, R, additional, Mucherino, C, additional, and Romano, M, additional

Published
2021
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32. SO-22 Gut microbiome composition as predictor of the efficacy of adding atezolizumab to first-line FOLFOXIRI plus bevacizumab in metastatic colorectal cancer: A translational analysis of the AtezoTRIBE study

Author

Marmorino, F., Piccinno, G., Rossini, D., Ghelardi, F., Murgioni, S., Salvatore, L., Nasca, V., Antoniotti, C., Daniel, F., Schietroma, F., Conca, V., Costa Silva, C. Alves, Tamburini, E., Tamberi, S., Passardi, A., Carullo, M., Antonuzzo, L., D'Onofrio, R., Zitvogel, L., Cremolini, C., and Derosa, L.

Published
2023
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33. Extreme Planktic Foraminiferal Dwarfism Across the ETM2 in the Tethys Realm in Response to Warming

Author

D’Onofrio, R., Barrett, R., Schmidt, D. N., Fornaciari, E., Giusberti, L., Frijia, G., Adatte, T., Sabatino, N., Monsuru, A., Brombin, V., and Luciani, V.

Abstract

Pronounced warming negatively impacts ecosystem resilience in modern oceans. To offer a long‐term geological perspective of the calcareous plankton response to global warming, we present an integrated record, from two Tethyan sections (northeastern Italy), of the planktic foraminiferal and calcareous nannofossil response to the Eocene Thermal Maximum 2 hyperthermal (ETM2, ∼54 Ma). Our study reveals pronounced changes in assemblage composition and a striking dwarfing of planktic foraminiferal tests of up to 40% during the event, impacting both surface and deeper dwellers. The increased abundance of small placoliths among calcareous nannofossils is interpreted as community size reduction. Literature and our foraminiferal size data from Sites 1263 and 1209 (Atlantic and Pacific Oceans) highlights that the pronounced dwarfism is restricted to the Tethyan area. The ETM2 is characterized by warm sea surface temperatures as indicated by our δ18O data, but this warming is of global extent and cannot explain the unique dwarfism. Excluding evolutionary modifications, other potential drivers of dwarfism (eutrophication, deoxygenation, metabolic adaptation) cannot explain the exceptional dwarfism by themselves. The smallest sizes are in close temporal association with peaks in volcanic derived Hg/Th‐Hg/Rb recorded just before and at the ETM2 which could not have been brought into our sections through weathering. In contrast, size reductions are absent below and above the ETM2 at Hg peaks where δ18O data do not show warm conditions. We speculate that the local input of toxic metals from submarine volcanic emissions could have acted synergistically to warming, causing the unique dwarfism. Calcareous plankton size in the Tethys during the Eocene Thermal Maximum 2 (ETM2) reveals marked dwarfismPronounced dwarfism was restricted to the Tethyan area, highlighting the importance of local signals in interpreting hyperthermalsCalcareous plankton were highly unstable across the ETM2 but ultimately resilient Calcareous plankton size in the Tethys during the Eocene Thermal Maximum 2 (ETM2) reveals marked dwarfism Pronounced dwarfism was restricted to the Tethyan area, highlighting the importance of local signals in interpreting hyperthermals Calcareous plankton were highly unstable across the ETM2 but ultimately resilient

Published
2024
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40. Erratum: Sequence data and association statistics from 12,940 type 2 diabetes cases and controls.

Author

Flannick, J, Fuchsberger, C, Mahajan, A, Teslovich, TM, Agarwala, V, Gaulton, KJ, Caulkins, L, Koesterer, R, Ma, C, Moutsianas, L, McCarthy, DJ, Rivas, MA, Perry, JRB, Sim, X, Blackwell, TW, Robertson, NR, Rayner, NW, Cingolani, P, Locke, AE, Tajes, JF, Highland, HM, Dupuis, J, Chines, PS, Lindgren, CM, Hartl, C, Jackson, AU, Chen, H, Huyghe, JR, van de Bunt, M, Pearson, RD, Kumar, A, Mueller-Nurasyid, M, Grarup, N, Stringham, HM, Gamazon, ER, Lee, J, Chen, Y, Scott, RA, Below, JE, Chen, P, Huang, J, Go, MJ, Stitzel, ML, Pasko, D, Parker, SCJ, Varga, TV, Green, T, Beer, NL, Day-Williams, AG, Ferreira, T, Fingerlin, T, Horikoshi, M, Hu, C, Huh, I, Ikram, MK, Kim, B-J, Kim, Y, Kim, YJ, Kwon, M-S, Lee, S, Lin, K-H, Maxwell, TJ, Nagai, Y, Wang, X, Welch, RP, Yoon, J, Zhang, W, Barzilai, N, Voight, BF, Han, B-G, Jenkinson, CP, Kuulasmaa, T, Kuusisto, J, Manning, A, Ng, MCY, Palmer, ND, Balkau, B, Stancakova, A, Abboud, HE, Boeing, H, Giedraitis, V, Prabhakaran, D, Gottesman, O, Scott, J, Carey, J, Kwan, P, Grant, G, Smith, JD, Neale, BM, Purcell, S, Butterworth, AS, Howson, JMM, Lee, HM, Lu, Y, Kwak, S-H, Zhao, W, Danesh, J, Lam, VKL, Park, KS, Saleheen, D, So, WY, Tam, CHT, Afzal, U, Aguilar, D, Arya, R, Aung, T, Chan, E, Navarro, C, Cheng, C-Y, Palli, D, Correa, A, Curran, JE, Rybin, D, Farook, VS, Fowler, SP, Freedman, BI, Griswold, M, Hale, DE, Hicks, PJ, Khor, C-C, Kumar, S, Lehne, B, Thuillier, D, Lim, WY, Liu, J, Loh, M, Musani, SK, Puppala, S, Scott, WR, Yengo, L, Tan, S-T, Taylor, HA, Thameem, F, Wilson, G, Wong, TY, Njolstad, PR, Levy, JC, Mangino, M, Bonnycastle, LL, Schwarzmayr, T, Fadista, J, Surdulescu, GL, Herder, C, Groves, CJ, Wieland, T, Bork-Jensen, J, Brandslund, I, Christensen, C, Koistinen, HA, Doney, ASF, Kinnunen, L, Esko, T, Farmer, AJ, Hakaste, L, Hodgkiss, D, Kravic, J, Lyssenko, V, Hollensted, M, Jorgensen, ME, Jorgensen, T, Ladenvall, C, Justesen, JM, Karajamaki, A, Kriebel, J, Rathmann, W, Lannfelt, L, Lauritzen, T, Narisu, N, Linneberg, A, Melander, O, Milani, L, Neville, M, Orho-Melander, M, Qi, L, Qi, Q, Roden, M, Rolandsson, O, Swift, A, Rosengren, AH, Stirrups, K, Wood, AR, Mihailov, E, Blancher, C, Carneiro, MO, Maguire, J, Poplin, R, Shakir, K, Fennell, T, DePristo, M, de Angelis, MH, Deloukas, P, Gjesing, AP, Jun, G, Nilsson, PM, Murphy, J, Onofrio, R, Thorand, B, Hansen, T, Meisinger, C, Hu, FB, Isomaa, B, Karpe, F, Liang, L, Peters, A, Huth, C, O'Rahilly, SP, Palmer, CNA, Pedersen, O, Rauramaa, R, Tuomilehto, J, Salomaa, V, Watanabe, RM, Syvanen, A-C, Bergman, RN, Bharadwaj, D, Bottinger, EP, Cho, YS, Chandak, GR, Chan, JC, Chia, KS, Daly, MJ, Ebrahim, SB, Langenberg, C, Elliott, P, Jablonski, KA, Lehman, DM, Jia, W, Ma, RCW, Pollin, TI, Sandhu, M, Tandon, N, Froguel, P, Barroso, I, Teo, YY, Zeggini, E, Loos, RJF, Small, KS, Ried, JS, DeFronzo, RA, Grallert, H, Glaser, B, Metspalu, A, Wareham, NJ, Walker, M, Banks, E, Gieger, C, Ingelsson, E, Im, HK, Illig, T, Franks, PW, Buck, G, Trakalo, J, Buck, D, Prokopenko, I, Magi, R, Lind, L, Farjoun, Y, Owen, KR, Gloyn, AL, Strauch, K, Tuomi, T, Kooner, JS, Lee, J-Y, Park, T, Donnelly, P, Morris, AD, Hattersley, AT, Bowden, DW, Collins, FS, Atzmon, G, Chambers, JC, Spector, TD, Laakso, M, Strom, TM, Bell, GI, Blangero, J, Duggirala, R, Tai, E, McVean, G, Hanis, CL, Wilson, JG, Seielstad, M, Frayling, TM, Meigs, JB, Cox, NJ, Sladek, R, Lander, ES, Gabriel, S, Mohlke, KL, Meitinger, T, Groop, L, Abecasis, G, Scott, LJ, Morris, AP, Kang, HM, Altshuler, D, Burtt, NP, Florez, JC, Boehnke, M, McCarthy, MI, Flannick, J, Fuchsberger, C, Mahajan, A, Teslovich, TM, Agarwala, V, Gaulton, KJ, Caulkins, L, Koesterer, R, Ma, C, Moutsianas, L, McCarthy, DJ, Rivas, MA, Perry, JRB, Sim, X, Blackwell, TW, Robertson, NR, Rayner, NW, Cingolani, P, Locke, AE, Tajes, JF, Highland, HM, Dupuis, J, Chines, PS, Lindgren, CM, Hartl, C, Jackson, AU, Chen, H, Huyghe, JR, van de Bunt, M, Pearson, RD, Kumar, A, Mueller-Nurasyid, M, Grarup, N, Stringham, HM, Gamazon, ER, Lee, J, Chen, Y, Scott, RA, Below, JE, Chen, P, Huang, J, Go, MJ, Stitzel, ML, Pasko, D, Parker, SCJ, Varga, TV, Green, T, Beer, NL, Day-Williams, AG, Ferreira, T, Fingerlin, T, Horikoshi, M, Hu, C, Huh, I, Ikram, MK, Kim, B-J, Kim, Y, Kim, YJ, Kwon, M-S, Lee, S, Lin, K-H, Maxwell, TJ, Nagai, Y, Wang, X, Welch, RP, Yoon, J, Zhang, W, Barzilai, N, Voight, BF, Han, B-G, Jenkinson, CP, Kuulasmaa, T, Kuusisto, J, Manning, A, Ng, MCY, Palmer, ND, Balkau, B, Stancakova, A, Abboud, HE, Boeing, H, Giedraitis, V, Prabhakaran, D, Gottesman, O, Scott, J, Carey, J, Kwan, P, Grant, G, Smith, JD, Neale, BM, Purcell, S, Butterworth, AS, Howson, JMM, Lee, HM, Lu, Y, Kwak, S-H, Zhao, W, Danesh, J, Lam, VKL, Park, KS, Saleheen, D, So, WY, Tam, CHT, Afzal, U, Aguilar, D, Arya, R, Aung, T, Chan, E, Navarro, C, Cheng, C-Y, Palli, D, Correa, A, Curran, JE, Rybin, D, Farook, VS, Fowler, SP, Freedman, BI, Griswold, M, Hale, DE, Hicks, PJ, Khor, C-C, Kumar, S, Lehne, B, Thuillier, D, Lim, WY, Liu, J, Loh, M, Musani, SK, Puppala, S, Scott, WR, Yengo, L, Tan, S-T, Taylor, HA, Thameem, F, Wilson, G, Wong, TY, Njolstad, PR, Levy, JC, Mangino, M, Bonnycastle, LL, Schwarzmayr, T, Fadista, J, Surdulescu, GL, Herder, C, Groves, CJ, Wieland, T, Bork-Jensen, J, Brandslund, I, Christensen, C, Koistinen, HA, Doney, ASF, Kinnunen, L, Esko, T, Farmer, AJ, Hakaste, L, Hodgkiss, D, Kravic, J, Lyssenko, V, Hollensted, M, Jorgensen, ME, Jorgensen, T, Ladenvall, C, Justesen, JM, Karajamaki, A, Kriebel, J, Rathmann, W, Lannfelt, L, Lauritzen, T, Narisu, N, Linneberg, A, Melander, O, Milani, L, Neville, M, Orho-Melander, M, Qi, L, Qi, Q, Roden, M, Rolandsson, O, Swift, A, Rosengren, AH, Stirrups, K, Wood, AR, Mihailov, E, Blancher, C, Carneiro, MO, Maguire, J, Poplin, R, Shakir, K, Fennell, T, DePristo, M, de Angelis, MH, Deloukas, P, Gjesing, AP, Jun, G, Nilsson, PM, Murphy, J, Onofrio, R, Thorand, B, Hansen, T, Meisinger, C, Hu, FB, Isomaa, B, Karpe, F, Liang, L, Peters, A, Huth, C, O'Rahilly, SP, Palmer, CNA, Pedersen, O, Rauramaa, R, Tuomilehto, J, Salomaa, V, Watanabe, RM, Syvanen, A-C, Bergman, RN, Bharadwaj, D, Bottinger, EP, Cho, YS, Chandak, GR, Chan, JC, Chia, KS, Daly, MJ, Ebrahim, SB, Langenberg, C, Elliott, P, Jablonski, KA, Lehman, DM, Jia, W, Ma, RCW, Pollin, TI, Sandhu, M, Tandon, N, Froguel, P, Barroso, I, Teo, YY, Zeggini, E, Loos, RJF, Small, KS, Ried, JS, DeFronzo, RA, Grallert, H, Glaser, B, Metspalu, A, Wareham, NJ, Walker, M, Banks, E, Gieger, C, Ingelsson, E, Im, HK, Illig, T, Franks, PW, Buck, G, Trakalo, J, Buck, D, Prokopenko, I, Magi, R, Lind, L, Farjoun, Y, Owen, KR, Gloyn, AL, Strauch, K, Tuomi, T, Kooner, JS, Lee, J-Y, Park, T, Donnelly, P, Morris, AD, Hattersley, AT, Bowden, DW, Collins, FS, Atzmon, G, Chambers, JC, Spector, TD, Laakso, M, Strom, TM, Bell, GI, Blangero, J, Duggirala, R, Tai, E, McVean, G, Hanis, CL, Wilson, JG, Seielstad, M, Frayling, TM, Meigs, JB, Cox, NJ, Sladek, R, Lander, ES, Gabriel, S, Mohlke, KL, Meitinger, T, Groop, L, Abecasis, G, Scott, LJ, Morris, AP, Kang, HM, Altshuler, D, Burtt, NP, Florez, JC, Boehnke, M, and McCarthy, MI

Abstract

This corrects the article DOI: 10.1038/sdata.2017.179.

Published
2018

44. Data Descriptor: Sequence data and association statistics from 12,940 type 2 diabetes cases and controls

Author

Flannick, J, Fuchsberger, C, Mahajan, A, Teslovich, TM, Agarwala, V, Gaulton, KJ, Caulkins, L, Koesterer, R, Ma, C, Moutsianas, L, McCarthy, DJ, Rivas, MA, Perry, JRB, Sim, X, Blackwell, TW, Robertson, NR, Rayner, NW, Cingolani, P, Locke, AE, Tajes, JF, Highland, HM, Dupuis, J, Chines, PS, Lindgren, CM, Hartl, C, Jackson, AU, Chen, H, Huyghe, JR, De Bunt, MV, Pearson, RD, Kumar, A, Muller-Nurasyid, M, Grarup, N, Stringham, HM, Gamazon, ER, Lee, J, Chen, Y, Scott, RA, Below, JE, Chen, P, Huang, J, Go, MJ, Stitzel, ML, Pasko, D, Parker, SCJ, Varga, TV, Green, T, Beer, NL, Day-Williams, AG, Ferreira, T, Fingerlin, T, Horikoshi, M, Hu, C, Huh, I, Ikram, MK, Kim, B-J, Kim, Y, Kim, YJ, Kwon, M-S, Lee, S, Lin, K-H, Maxwell, TJ, Nagai, Y, Wang, X, Welch, RP, Yoon, J, Zhang, W, Barzilai, N, Voight, BF, Han, B-G, Jenkinson, CP, Kuulasmaa, T, Kuusisto, J, Manning, A, Ng, MCY, Palmer, ND, Balkau, B, Stancakova, A, Abboud, HE, Boeing, H, Giedraitis, V, Prabhakaran, D, Gottesman, O, Scott, J, Carey, J, Kwan, P, Grant, G, Smith, JD, Neale, BM, Purcell, S, Butterworth, AS, Howson, JMM, Lee, HM, Lu, Y, Kwak, S-H, Zhao, W, Danesh, J, Lam, VKL, Park, KS, Saleheen, D, So, WY, Tam, CHT, Afzal, U, Aguilar, D, Arya, R, Aung, T, Chan, E, Navarro, C, Cheng, C-Y, Palli, D, Correa, A, Curran, JE, Rybin, D, Farook, VS, Fowler, SP, Freedman, BI, Griswold, M, Hale, DE, Hicks, PJ, Khor, C-C, Kumar, S, Lehne, B, Thuillier, D, Lim, WY, Liu, J, Loh, M, Musani, SK, Puppala, S, Scott, WR, Yengo, L, Tan, S-T, Taylor, HA, Thameem, F, Wilson, G, Wong, TY, Njolstad, PR, Levy, JC, Mangino, M, Bonnycastle, LL, Schwarzmayr, T, Fadista, J, Surdulescu, GL, Herder, C, Groves, CJ, Wieland, T, Bork-Jensen, J, Brandslund, I, Christensen, C, Koistinen, HA, Doney, ASF, Kinnunen, L, Esko, T, Farmer, AJ, Hakaste, L, Hodgkiss, D, Kravic, J, Lyssenko, V, Hollensted, M, Jorgensen, ME, Jorgensen, T, Ladenvall, C, Justesen, JM, Karajamaki, A, Kriebel, J, Rathmann, W, Lannfelt, L, Lauritzen, T, Narisu, N, Linneberg, A, Melander, O, Milani, L, Neville, M, Orho-Melander, M, Qi, L, Qi, Q, Roden, M, Rolandsson, O, Swift, A, Rosengren, AH, Stirrups, K, Wood, AR, Mihailov, E, Blancher, C, Carneiro, MO, Maguire, J, Poplin, R, Shakir, K, Fennell, T, DePristo, M, De Angelis, MH, Deloukas, P, Gjesing, AP, Jun, G, Nilsson, PM, Murphy, J, Onofrio, R, Thorand, B, Hansen, T, Meisinger, C, Hu, FB, Isomaa, B, Karpe, F, Liang, L, Peters, A, Huth, C, O'Rahilly, SP, Palmer, CNA, Pedersen, O, Rauramaa, R, Tuomilehto, J, Salomaa, V, Watanabe, RM, Syvanen, A-C, Bergman, RN, Bharadwaj, D, Bottinger, EP, Cho, YS, Chandak, GR, Chan, JC, Chia, KS, Daly, MJ, Ebrahim, SB, Langenberg, C, Elliott, P, Jablonski, KA, Lehman, DM, Jia, W, Ma, RC, Pollin, TI, Sandhu, M, Tandon, N, Froguel, P, Barroso, I, Teo, YY, Zeggini, E, Loos, RJF, Small, KS, Ried, JS, DeFronzo, RA, Grallert, H, Glaser, B, Metspalu, A, Wareham, NJ, Walker, M, Banks, E, Gieger, C, Ingelsson, E, Im, HK, Illig, T, Franks, PW, Buck, G, Trakalo, J, Buck, D, Prokopenko, I, Magi, R, Lind, L, Farjoun, Y, Owen, KR, Gloyn, AL, Strauch, K, Tuomi, T, Kooner, JS, Lee, J-Y, Park, T, Donnelly, P, Morris, AD, Hattersley, AT, Bowden, DW, Collins, FS, Atzmon, G, Chambers, JC, Spector, TD, Laakso, M, Strom, TM, Bell, GI, Blangero, J, Duggirala, R, Tai, E, McVean, G, Hanis, CL, Wilson, JG, Seielstad, M, Frayling, TM, Meigs, JB, Cox, NJ, Sladek, R, Lander, ES, Gabriel, S, Mohlke, KL, Meitinger, T, Groop, L, Abecasis, G, Scott, LJ, Morris, AP, Kang, HM, Altshuler, D, Burtt, NP, Florez, JC, Boehnke, M, McCarthy, MI, Flannick, J, Fuchsberger, C, Mahajan, A, Teslovich, TM, Agarwala, V, Gaulton, KJ, Caulkins, L, Koesterer, R, Ma, C, Moutsianas, L, McCarthy, DJ, Rivas, MA, Perry, JRB, Sim, X, Blackwell, TW, Robertson, NR, Rayner, NW, Cingolani, P, Locke, AE, Tajes, JF, Highland, HM, Dupuis, J, Chines, PS, Lindgren, CM, Hartl, C, Jackson, AU, Chen, H, Huyghe, JR, De Bunt, MV, Pearson, RD, Kumar, A, Muller-Nurasyid, M, Grarup, N, Stringham, HM, Gamazon, ER, Lee, J, Chen, Y, Scott, RA, Below, JE, Chen, P, Huang, J, Go, MJ, Stitzel, ML, Pasko, D, Parker, SCJ, Varga, TV, Green, T, Beer, NL, Day-Williams, AG, Ferreira, T, Fingerlin, T, Horikoshi, M, Hu, C, Huh, I, Ikram, MK, Kim, B-J, Kim, Y, Kim, YJ, Kwon, M-S, Lee, S, Lin, K-H, Maxwell, TJ, Nagai, Y, Wang, X, Welch, RP, Yoon, J, Zhang, W, Barzilai, N, Voight, BF, Han, B-G, Jenkinson, CP, Kuulasmaa, T, Kuusisto, J, Manning, A, Ng, MCY, Palmer, ND, Balkau, B, Stancakova, A, Abboud, HE, Boeing, H, Giedraitis, V, Prabhakaran, D, Gottesman, O, Scott, J, Carey, J, Kwan, P, Grant, G, Smith, JD, Neale, BM, Purcell, S, Butterworth, AS, Howson, JMM, Lee, HM, Lu, Y, Kwak, S-H, Zhao, W, Danesh, J, Lam, VKL, Park, KS, Saleheen, D, So, WY, Tam, CHT, Afzal, U, Aguilar, D, Arya, R, Aung, T, Chan, E, Navarro, C, Cheng, C-Y, Palli, D, Correa, A, Curran, JE, Rybin, D, Farook, VS, Fowler, SP, Freedman, BI, Griswold, M, Hale, DE, Hicks, PJ, Khor, C-C, Kumar, S, Lehne, B, Thuillier, D, Lim, WY, Liu, J, Loh, M, Musani, SK, Puppala, S, Scott, WR, Yengo, L, Tan, S-T, Taylor, HA, Thameem, F, Wilson, G, Wong, TY, Njolstad, PR, Levy, JC, Mangino, M, Bonnycastle, LL, Schwarzmayr, T, Fadista, J, Surdulescu, GL, Herder, C, Groves, CJ, Wieland, T, Bork-Jensen, J, Brandslund, I, Christensen, C, Koistinen, HA, Doney, ASF, Kinnunen, L, Esko, T, Farmer, AJ, Hakaste, L, Hodgkiss, D, Kravic, J, Lyssenko, V, Hollensted, M, Jorgensen, ME, Jorgensen, T, Ladenvall, C, Justesen, JM, Karajamaki, A, Kriebel, J, Rathmann, W, Lannfelt, L, Lauritzen, T, Narisu, N, Linneberg, A, Melander, O, Milani, L, Neville, M, Orho-Melander, M, Qi, L, Qi, Q, Roden, M, Rolandsson, O, Swift, A, Rosengren, AH, Stirrups, K, Wood, AR, Mihailov, E, Blancher, C, Carneiro, MO, Maguire, J, Poplin, R, Shakir, K, Fennell, T, DePristo, M, De Angelis, MH, Deloukas, P, Gjesing, AP, Jun, G, Nilsson, PM, Murphy, J, Onofrio, R, Thorand, B, Hansen, T, Meisinger, C, Hu, FB, Isomaa, B, Karpe, F, Liang, L, Peters, A, Huth, C, O'Rahilly, SP, Palmer, CNA, Pedersen, O, Rauramaa, R, Tuomilehto, J, Salomaa, V, Watanabe, RM, Syvanen, A-C, Bergman, RN, Bharadwaj, D, Bottinger, EP, Cho, YS, Chandak, GR, Chan, JC, Chia, KS, Daly, MJ, Ebrahim, SB, Langenberg, C, Elliott, P, Jablonski, KA, Lehman, DM, Jia, W, Ma, RC, Pollin, TI, Sandhu, M, Tandon, N, Froguel, P, Barroso, I, Teo, YY, Zeggini, E, Loos, RJF, Small, KS, Ried, JS, DeFronzo, RA, Grallert, H, Glaser, B, Metspalu, A, Wareham, NJ, Walker, M, Banks, E, Gieger, C, Ingelsson, E, Im, HK, Illig, T, Franks, PW, Buck, G, Trakalo, J, Buck, D, Prokopenko, I, Magi, R, Lind, L, Farjoun, Y, Owen, KR, Gloyn, AL, Strauch, K, Tuomi, T, Kooner, JS, Lee, J-Y, Park, T, Donnelly, P, Morris, AD, Hattersley, AT, Bowden, DW, Collins, FS, Atzmon, G, Chambers, JC, Spector, TD, Laakso, M, Strom, TM, Bell, GI, Blangero, J, Duggirala, R, Tai, E, McVean, G, Hanis, CL, Wilson, JG, Seielstad, M, Frayling, TM, Meigs, JB, Cox, NJ, Sladek, R, Lander, ES, Gabriel, S, Mohlke, KL, Meitinger, T, Groop, L, Abecasis, G, Scott, LJ, Morris, AP, Kang, HM, Altshuler, D, Burtt, NP, Florez, JC, Boehnke, M, and McCarthy, MI

Abstract

To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1-5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (>80% of low-frequency coding variants in ~82 K Europeans via the exome chip, and ~90% of low-frequency non-coding variants in ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D.

Published
2017

46. Identification and Functional Characterization of G6PC2 Coding Variants Influencing Glycemic Traits Define an Effector Transcript at the G6PC2-ABCB11 Locus

Author

Mahajan, A., Sim, X., Ng, H.J., Manning, A., Rivas, M.A., Highland, H.M., Locke, A.E., Grarup, N., Im, H.K., Cingolani, P., Flannick, J., Fontanillas, P., Fuchsberger, C., Gaulton, K.J., Teslovich, T.M., Rayner, N.W., Robertson, N.R., Beer, N.L., Rundle, J.K., Bork-Jensen, J., Ladenvall, C., Blancher, C., Buck, D., Buck, G., Burtt, N.P., Gabriel, S., Gjesing, A.P., Groves, C.J., Hollensted, M., Huyghe, J.R., Jackson, A.U., Jun, G., Justesen, J.M., Mangino, M., Murphy, J., Neville, M., Onofrio, R., Small, K.S., Stringham, H.M., Syvanen, A.C., Trakalo, J., Abecasis, G., Bell, G.I., Blangero, J., Cox, N.J., Duggirala, R., Hanis, C.L., Seielstad, M., Wilson, J.G., Christensen, C., Brandslund, I., Rauramaa, R., Surdulescu, G.L., Doney, A.S., Lannfelt, L., Linneberg, A., Isomaa, B., Tuomi, T., Jørgensen, M.E., Jørgensen, T., Kuusisto, J., Uusitupa, M., Salomaa, V., Spector, T.D., Morris, A.D., Palmer, C.N., Collins, F.S., Mohlke, K.L., Bergman, R.N., Ingelsson, E., Lind, L., Tuomilehto, J., Hansen, T., Watanabe, R.M., Prokopenko, I., Dupuis, J., Karpe, F., Groop, L., Laakso, M., Pedersen, O., Florez, J.C, Morris, A.P., Altshuler, D., Meigs, J.B., Boehnke, M., McCarthy, M.I., Lindgren, C.M., Gloyn, A.L., T2D-GENES Consortium (), GoT2D Consortium (Hrabě de Angelis, M., Gieger, C., Grallert, H., Huth, C., Kriebel, J., Meisinger, C., Meitinger, T., Müller-Nurasyid, M., Peters, A., Ried, J.S., Strauch, K., and Strom, T.M.)

Subjects
Blood Glucose, Endocrinology and Diabetes, Polymorphism, Single Nucleotide, Glucagon-Like Peptide-1 Receptor, Diabetes Mellitus, Type 2, Gene Frequency, Glycemic Index, Glucose-6-Phosphatase, Receptors, Glucagon, Humans, Insulin, Exome, Medical Genetics, Research Article, Genome-Wide Association Study, Medicinsk genetik
Abstract

Genome wide association studies (GWAS) for fasting glucose (FG) and insulin (FI) have identified common variant signals which explain 4.8% and 1.2% of trait variance, respectively. It is hypothesized that low-frequency and rare variants could contribute substantially to unexplained genetic variance. To test this, we analyzed exome-array data from up to 33,231 non-diabetic individuals of European ancestry. We found exome-wide significant (P, Author Summary Understanding how FI and FG levels are regulated is important because their derangement is a feature of T2D. Despite recent success from GWAS in identifying regions of the genome influencing glycemic traits, collectively these loci explain only a small proportion of trait variance. Unlocking the biological mechanisms driving these associations has been challenging because the vast majority of variants map to non-coding sequence, and the genes through which they exert their impact are largely unknown. In the current study, we sought to increase our understanding of the physiological pathways influencing both traits using exome-array genotyping in up to 33,231 non-diabetic individuals to identify coding variants and consequently genes associated with either FG or FI levels. We identified novel association signals for both traits including the receptor for GLP-1 agonists which are a widely used therapy for T2D. Furthermore, we identified coding variants at several GWAS loci which point to the genes underlying these association signals. Importantly, we found that multiple coding variants in G6PC2 result in a loss of protein function and lower fasting glucose levels.

Published
2015

50. Massive and permanent decline of symbiont bearing morozovellids and δ13C perturbations across the Early Eocene Climatic Optimum at the Possagno section (Southern Alps of northeastern Italy).

Author

Luciani, V., Backman, J., Fornaciari, E., Giusberti, L., Agnini, C., and D'Onofrio, R.

Abstract

The Early Eocene Climatic Optimum (EECO) records the highest prolonged global temperatures over the past 70 Ma. Understanding the causes and timing of Eocene climate change remains a major challenge in Cenozoic paleoceanography, which includes the biotic response to climate variability and the changes among planktic foraminifer5 al assemblages across the EECO. The symbiont bearing and shallow dwelling genera Morozovella and Acarinina were important calcifiers in the tropical-subtropical early Paleogene oceans but almost completely disappeared at about 38 Ma, near the Bartonian/ Priabonian boundary. We show here that morozovellids record a first critical step across the EECO through a major permanent decline in relative abundance from the Tethyan Possagno section and ODP Site 1051 in the western subtropical North Atlantic. Possible causes may include increased eutrophication, weak water column stratification, changes in ocean chemistry, loss of symbiosis and possible complex interaction with other microfossil groups. Relative abundances of planktic foraminiferal taxa at Possagno parallel negative shifts in both δ13C and δ18O of bulk sediment from Chron C24r to basal Chron C20r. The post-EECO stable isotopic excursions towards lighter values are of modest intensity. Significant though ephemeral modifications in the planktic foraminiferal communities occur during these minor isotopic excursions. These modifications are marked by pronounced increases in relative abundance of acarininids, in a manner similar to their behaviour during pre-EECO hyperthermals in the Tethyan settings, which suggest a pronounced biotic sensitivity to climate change of planktic foraminifera even during the post-EECO interval. [ABSTRACT FROM AUTHOR]

Published
2015
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