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2. Infiltrating Lobular Carcinoma of the Breast Presenting as Gastrointestinal Obstruction: A Mini Review

Author

P Carcoforo, MT Raiji, RC Langan, S Lanzara, M Portinari, U Maestroni, GM Palini, MV Zanzi, S Bonazza, M Pedriali, CV Feo, A Stojadinovic, I Avital

Subjects
Neoplasms. Tumors. Oncology. Including cancer and carcinogens, RC254-282
Abstract

One in twelve American women will develop breast cancer, with infiltrating lobular carcinoma (ILC) comprising approximately 15% of these cases. The incidence of ILC has been increasing over the last several decades. It has been hypothesized that this increase is associated with combined replacement hormonal therapy. Although pathologically distinct from infiltrating ductal carcinoma (IDC), ILC is treated in the same manner as IDC. However, ILC demonstrates significantly different patterns of late local recurrence and distant metastasis. The incidence of extra-hepatic gastrointestinal metastases is reported to be 6% to 18%, with stomach being most common. Herein, we present a brief review of the literature and a typical case involving ILC initially presenting as a small bowel obstruction. Evidence suggests that the late clinical patterns of ILC are distinctly separate from IDC and physicians need be cognizant of its late local recurrence and unique late metastatic pattern. Different follow up strategy should be entertained in patients with ILC.

Published
2012

3. CARTE VERDI NELL’ARCHIVIO DI STATO DI MODENA: L’ERBARIO ESTENSE, FOGLIE TRA I FOGLI, UN REBUS, UN PROGETTO. PARTE II

Author

Vicentini C. B., Buldrini F., Bosi G., Bonazza M., Romagnoli C., and Vicentini C.B., Buldrini F., Bosi G., Bonazza M., Romagnoli C.

Subjects
non previste dalla rivista
Abstract

The Este Herbarium, preserved in the Este Secret Archives of the Modena State Archives, is one of the few surviving Renaissance herbaria to date. It is the most fascinating and mysterious. It is probably the sixth volume of a lost series. In the present article, we discuss the results of a joint work (still in progress) among the Universities of Ferrara, Modena and Reggio Emilia, and Bologna. All the correspondence between simplists and botanists of that epoch (primarily Ulisse Aldrovandi from Bologna) was thoroughly analysed, to search the solution of the rebus: which author (or authors), which temporal location, which context of production for this herbarium? The documents consulted allow to understand that living plants, seeds and illustrations were commonly exchanged, but herbarium sheets never. The consultations on taxonomic attributions were frequent. The term herbario/herbarj, that is recurring in the letters written by Alfonso Cattaneo to Ulisse Aldrovandi, is also mysterious (thing or person?).

Published
2020

5. Atmospheric synoptic conditions of snow precipitation in East Antarctica using ice core and reanalysis data

Author

Scarchilli, C., Ciardini, V., Bonazza, M., Frezzotti, M., Stenni, Barbara, European Geosciences Union, C., Scarchilli, V., Ciardini, Bonazza, Mattia, M., Frezzotti, and Stenni, Barbara

Subjects
snow accumulation, IPCS, Antarctica, ice core
Abstract

In the framework of the International Partnerships in Ice Core Sciences (IPCS) initiatives the GV7 site (70°41’ S – 158°51’ E) in East Antarctica was chosen as the new drilling site for the Italian contribution to the understanding of the climatic variability in the last 2000 years (IPICS 2k Array). Water stable isotopes and snow accumulation (SMB) values from a shallow firn core, obtained at GV7 during the 2001-2002 International Trans-Antarctic Scientific Expedition (ITASE) traverse, are analyzed and compared with different meteorological model output in order to characterize the atmospheric synoptic conditions driving precipitation events at the site. On annual basis, ECMWF +24h forecasted snowfalls (SF) seem to well reproduce GV7 SMB values trend for the period from 1980 to 2005. Calculated air mass back-trajectories show that Eastern Indian - Western Pacific oceans represent the main moisture path toward the site during autumn - winter season. Analysis of the ECMWF 500 hPa Geopotential height field (GP500) anomalies shows that atmospheric blocking events developing between 130°E and 150°W at high latitudes drive the GV7 SMB by blocking zonal flow and conveying warm and moist deep air masses from ocean into the continental interior. On inter-annual basis, The SF variability over GV7 region follows the temporal oscillation of the third CEOF mode (CEOF3 10% of the total explained variance) of a combined complex empirical orthogonal function (CEOF) performed over GP500 and SF field. The CEOF3 highlights an oscillating feature, with wavenumber 2, in GP500 field over the Western Pacific-Eastern Indian Oceans and propagating westward. The pattern is deeply correlated with the Indian Dipole Oscillation and ENSO and their associated quasi-stationary Rossby waves propagating from the lower toward the higher latitudes.

Published
2014

7. Technical Note: Evaluation of between-sample memory effects in the analysis of ?2H and ?18O of water samples measured by laser spectroscopes

Author

Penna, D., Stenni, B., Sanda, M., Wrede, S., Bogaard, T.A., Michelini, M., Fischer, B.M.C., Gobbi, A., Mantese, N., Zuecco, G., Borga, M., Bonazza, M., Sobotkova, M., Cejkova, B., and Wassenaar, L.I.

Abstract

This study evaluated between-sample memory in isotopic measurements of ?2H and ?18O in water samples by laser spectroscopy. Ten isotopically depleted water samples spanning a broad range of oxygen and hydrogen isotopic compositions were measured by three generations of offaxis integrated cavity output spectroscopy and cavity ringdown spectroscopy instruments. The analysis procedure encompassed small (less than 2‰ for ?2H and 1‰ for ?18O) and large (up to 201‰ for ?2H and 25‰ for ?18O) differences in isotopic compositions between adjacent sample vials. Samples were injected 18 times each, and the betweensample memory effect was quantified for each analysis run. Results showed that samples adversely affected by betweensample isotopic differences stabilised after seven–eight injections. The between-sample memory effect ranged from 14% and 9% for ?2H and ?18O measurements, respectively, but declined to negligible carryover (between 0.1% and 0.3% for both isotopes) when the first ten injections of each sample were discarded. The measurement variability (range and standard deviation) was strongly dependent on the isotopic difference between adjacent vials. Standard deviations were up to 7.5‰for ?2H and 0.54‰for ?18O when all injections were retained in the computation of the reportable ?-value, but a significant increase in measurement precision (standard deviation in the range 0.1 ‰–1.0‰ for ?2H and 0.05‰– 0.17‰for ?18O) was obtained when the first eight injections were discarded. In conclusion, this study provided a practical solution to mitigate between-sample memory effects in the isotopic analysis of water samples by laser spectroscopy.

Published
2012

9. Technical Note: Evaluation of between-sample memory effects in the analysis of δ2h and δ18o of water samples measured by laser spectroscopes

Author

Penna, D., Stenni, Barbara, Šanda, M., Wrede, S., Bogaard, T. A., Michelini, M., Fischer, B. M. C., Gobbi, A., Mantese, N., Zuecco, G., Borga, M., Bonazza, M., Sobotková, M., Cejková, B., Wassenaar, L. I., University of Zurich, Penna, D, Penna, D., Stenni, Barbara, Šanda, M., Wrede, S., Bogaard, T. A., Michelini, Marzia, Fischer, B. M. C., Gobbi, A., Mantese, N., Zuecco, G., Borga, M., Bonazza, Mattia, Sobotková, M., Cejková, B., and Wassenaar, L. I.

Subjects
Oxygen and hydrogen stable isotope, Isotopic analysis, Runoff generation, 10122 Institute of Geography, 2312 Water Science and Technology, 1901 Earth and Planetary Sciences (miscellaneous), memory effect, 910 Geography & travel, laser specroscope, Oxygen and hydrogen stable isotopes
Published
2012

12. On the reproducibility and repeatability of laser absorption spectroscopy measurements for δ2H and δ18O isotopic analysis

Author

Penna, D., Stenni, Barbara, Šanda, M., Wrede, S., Bogaard, T. A., Gobbi, A., Borga, M., Fischer, B. M. C., Bonazza, M., Chárová, Z., University of Zurich, Penna, D, Penna, D., Stenni, Barbara, Šanda, M., Wrede, S., Bogaard, T. A., Gobbi, A., Borga, M., Fischer, B. M. C., Bonazza, Mattia, and Chárová, Z.

Subjects
water samples, lcsh:GE1-350, oxygen and hydrogen isotopes, lcsh:T, 1901 Earth and Planetary Sciences (miscellaneous), lcsh:Geography. Anthropology. Recreation, lcsh:Technology, lcsh:TD1-1066, oxygen and hydrogen isotope, 10122 Institute of Geography, 2312 Water Science and Technology, laser spectroscope, mass spectrometer, lcsh:G, water sample, 910 Geography & travel, lcsh:Environmental technology. Sanitary engineering, lcsh:Environmental sciences
Abstract

The aim of this study was to analyse the reproducibility of off-axis integrated cavity output spectroscopy (OA-ICOS)-derived δ2H and δ18O measurements on a set of 35 water samples by comparing the performance of four laser spectroscopes with the performance of a conventional mass spectrometer under typical laboratory conditions. All samples were analysed using three different schemes of standard/sample combinations and related data processing to assess the improvement of results compared with mass spectrometry. The repeatability of the four OA-ICOS instruments was further investigated by multiple analyses of a sample subset to evaluate the stability of δ2H and δ18O measurements. Results demonstrated an overall agreement between OA-ICOS-based and mass spectrometry-based measurements for the entire dataset. However, a certain degree of variability existed in precision and accuracy between the four instruments. There was no evident bias or systematic deviations from the mass spectrometer values, but random errors, which were apparently not related to external factors, significantly affected the final results. Our investigation revealed that analytical precision ranged ±from ±0.56‰ to ±1.80‰ for δ2H and from ±0.10‰ to ±0.27‰ for δ18O measurements, with a marked variability among the four instruments. The overall capability of laser instruments to reproduce stable results with repeated measurements of the same sample was acceptable, and there were general differences within the range of the analytical precision for each spectroscope. Hence, averaging the measurements of three identical samples led to a higher degree of accuracy and eliminated the potential for random deviations.

Published
2010
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15. Technical Note: Evaluation of between-sample memory effects in the analysis of δ2H and δ18O of water samples measured by laser spectroscopes

Author

Penna, D, Stenni, B, Šanda, M, Wrede, S, Bogaard, T A, Michelini, M, Fischer, Benjamin M C, Gobbi, A, Mantese, N, Zuecco, G, Borga, M, Bonazza, M, Sobotková, M, Čejková, B, Wassenaar, L I, Penna, D, Stenni, B, Šanda, M, Wrede, S, Bogaard, T A, Michelini, M, Fischer, Benjamin M C, Gobbi, A, Mantese, N, Zuecco, G, Borga, M, Bonazza, M, Sobotková, M, Čejková, B, and Wassenaar, L I

Abstract

This study evaluated between-sample memory in isotopic measurements of δ2H and δ18O in water samples by laser spectroscopy. Ten isotopically depleted water samples spanning a broad range of oxygen and hydrogen isotopic compositions were measured by three generations of off-axis integrated cavity output spectroscopy and cavity ringdown spectroscopy instruments. The analysis procedure encompassed small (less than 2 ‰ for δ2H and 1 ‰ for δ18O) and large (up to 201‰ for δ2H and 25‰ for δ18O) differences in isotopic compositions between adjacent sample vials. Samples were injected 18 times each, and the between-sample memory effect was quantified for each analysis run. Results showed that samples adversely affected by between-sample isotopic differences stabilised after seven–eight injections. The between-sample memory effect ranged from 14 % and 9% for δ2H and δ18O measurements, respectively, but declined to negligible carryover (between 0.1 % and 0.3 % for both isotopes) when the first ten injections of each sample were discarded. The measurement variability (range and standard deviation) was strongly dependent on the isotopic difference between adjacent vials. Standard deviations were up to 7.5 ‰ for δ2H and 0.54 ‰ for δ18O when all injections were retained in the computation of the reportable δ-value, but a significant increase in measurement precision (standard deviation in the range 0.1 ‰–1.0 ‰ for δ2H and 0.05 ‰–0.17 ‰ for δ18O) was obtained when the first eight injections were discarded. In conclusion, this study provided a practical solution to mitigate between-sample memory effects in the isotopic analysis of water samples by laser spectroscopy.

Published
2012

16. Technical Note: Evaluation of between-sample memory effects in the analysis of ?2H and ?18O of water samples measured by laser spectroscopes

Author

Penna, D. (author), Stenni, B. (author), Sanda, M. (author), Wrede, S. (author), Bogaard, T.A. (author), Michelini, M. (author), Fischer, B.M.C. (author), Gobbi, A. (author), Mantese, N. (author), Zuecco, G. (author), Borga, M. (author), Bonazza, M. (author), Sobotkova, M. (author), Cejkova, B. (author), Wassenaar, L.I. (author), Penna, D. (author), Stenni, B. (author), Sanda, M. (author), Wrede, S. (author), Bogaard, T.A. (author), Michelini, M. (author), Fischer, B.M.C. (author), Gobbi, A. (author), Mantese, N. (author), Zuecco, G. (author), Borga, M. (author), Bonazza, M. (author), Sobotkova, M. (author), Cejkova, B. (author), and Wassenaar, L.I. (author)

Abstract

This study evaluated between-sample memory in isotopic measurements of ?2H and ?18O in water samples by laser spectroscopy. Ten isotopically depleted water samples spanning a broad range of oxygen and hydrogen isotopic compositions were measured by three generations of offaxis integrated cavity output spectroscopy and cavity ringdown spectroscopy instruments. The analysis procedure encompassed small (less than 2‰ for ?2H and 1‰ for ?18O) and large (up to 201‰ for ?2H and 25‰ for ?18O) differences in isotopic compositions between adjacent sample vials. Samples were injected 18 times each, and the betweensample memory effect was quantified for each analysis run. Results showed that samples adversely affected by betweensample isotopic differences stabilised after seven–eight injections. The between-sample memory effect ranged from 14% and 9% for ?2H and ?18O measurements, respectively, but declined to negligible carryover (between 0.1% and 0.3% for both isotopes) when the first ten injections of each sample were discarded. The measurement variability (range and standard deviation) was strongly dependent on the isotopic difference between adjacent vials. Standard deviations were up to 7.5‰for ?2H and 0.54‰for ?18O when all injections were retained in the computation of the reportable ?-value, but a significant increase in measurement precision (standard deviation in the range 0.1 ‰–1.0‰ for ?2H and 0.05‰– 0.17‰for ?18O) was obtained when the first eight injections were discarded. In conclusion, this study provided a practical solution to mitigate between-sample memory effects in the isotopic analysis of water samples by laser spectroscopy., Water Management, Civil Engineering and Geosciences

Published
2012
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17. Expression of the bipolar see-saw in Antarctic climate records during the last deglaciation

Author

Stenni, B., Buiron, D., Frezzoti, M., Albani, S., Barbante, C., Bard, E., Barnola, J. M., Baroni, M., Baumgartner, M., Bonazza, M., Capron, E., Castellano, E., Chappellaz, J., Delmonte, B., Falourd, S., Genoni, L., Iacumin, P., Jouzel, J., Kipfstuhl, Sepp, Landais, A., Lemieux-Dudon, B., Maggi, V., Masson-Delmotte, V., Mazzola, C., Minster, B., Montagnat, M., Mulvaney, R., Narcisi, B., Oerter, Hans, Parrenin, F., Petit, J. R., Ritz, C., Scarchilli, C., Schilt, A., Schüpbach, S., Schwander, J., Selmo, E., Severi, M., Stocker, T. F., Udisti, R., Stenni, B., Buiron, D., Frezzoti, M., Albani, S., Barbante, C., Bard, E., Barnola, J. M., Baroni, M., Baumgartner, M., Bonazza, M., Capron, E., Castellano, E., Chappellaz, J., Delmonte, B., Falourd, S., Genoni, L., Iacumin, P., Jouzel, J., Kipfstuhl, Sepp, Landais, A., Lemieux-Dudon, B., Maggi, V., Masson-Delmotte, V., Mazzola, C., Minster, B., Montagnat, M., Mulvaney, R., Narcisi, B., Oerter, Hans, Parrenin, F., Petit, J. R., Ritz, C., Scarchilli, C., Schilt, A., Schüpbach, S., Schwander, J., Selmo, E., Severi, M., Stocker, T. F., and Udisti, R.

Published
2011

18. Expression of the bipolar seesaw in Antarctic climate records during the last deglaciation

Author

Stenni, B, Buiron, D, Frezzotti, M, Albani, S, Barbante, C, Bard, E, Barnola, J, Baroni, M, Baumgartner, M, Bonazza, M, Capron, E, Castellano, E, Chappellaz, J, Delmonte, B, Falourd, S, Genoni, L, Iacumin, P, Jouzel, J, Kipfstuhl, S, Landais, A, Lemieux Dudon, B, Maggi, V, Masson Delmotte, V, Mazzola, C, Minster, B, Montagnat, M, Mulvaney, R, Narcisi, B, Oerter, H, Parrenin, F, Petit, J, Ritz, C, Scarchilli, C, Schilt, A, Schüpbach, S, Schwander, J, Selmo, E, Severi, M, Stocker, T, Udisti, R, Barnola, JM, Petit, JR, Stocker, TF, Udisti, R., ALBANI, SAMUEL, DELMONTE, BARBARA, MAGGI, VALTER, MAZZOLA, CLAUDIA MARIA GABRIELLA, Stenni, B, Buiron, D, Frezzotti, M, Albani, S, Barbante, C, Bard, E, Barnola, J, Baroni, M, Baumgartner, M, Bonazza, M, Capron, E, Castellano, E, Chappellaz, J, Delmonte, B, Falourd, S, Genoni, L, Iacumin, P, Jouzel, J, Kipfstuhl, S, Landais, A, Lemieux Dudon, B, Maggi, V, Masson Delmotte, V, Mazzola, C, Minster, B, Montagnat, M, Mulvaney, R, Narcisi, B, Oerter, H, Parrenin, F, Petit, J, Ritz, C, Scarchilli, C, Schilt, A, Schüpbach, S, Schwander, J, Selmo, E, Severi, M, Stocker, T, Udisti, R, Barnola, JM, Petit, JR, Stocker, TF, Udisti, R., ALBANI, SAMUEL, DELMONTE, BARBARA, MAGGI, VALTER, and MAZZOLA, CLAUDIA MARIA GABRIELLA

Abstract

Ice-core records of climate from Greenland and Antarctica show asynchronous temperature variations on millennial timescales during the last glacial period. The warming during the transition from glacial to interglacial conditions was markedly different between the hemispheres, a pattern attributed to the thermal bipolar see-saw. However, a record from the Ross Sea sector of East Antarctica has been suggested to be synchronous with Northern Hemisphere climate change. Here we present a temperature record from the Talos Dome ice core, also located in the Ross Sea sector. We compare our record with ice-core analyses from Greenland, based on methane synchronization, and find clearly asynchronous temperature changes during the deglaciation. We also find distinct differences in Antarctic records, pointing to differences in the climate evolution of the Indo-Pacific and Atlantic sectors of Antarctica. In the Atlantic sector, we find that the rate of warming slowed between 16,000 and 14,500 years ago, parallel with the deceleration of the rise in atmospheric carbon dioxide concentrations and with a slight cooling over Greenland. In addition, our chronology supports the hypothesis that the cooling of the Antarctic Cold Reversal is synchronous with the Bølling-Allerød warming in the northern hemisphere 14,700 years ago. © 2011 Macmillan Publishers Limited. All rights reserved.

Published
2011

20. Technical Note: Evaluation of between-sample memory effects in the analysis of δ<sup>2</sup>H and δ<sup>18</sup>O of water samples measured by laser spectroscopes

Author

Penna, D., primary, Stenni, B., additional, Šanda, M., additional, Wrede, S., additional, Bogaard, T. A., additional, Michelini, M., additional, Fischer, B. M. C., additional, Gobbi, A., additional, Mantese, N., additional, Zuecco, G., additional, Borga, M., additional, Bonazza, M., additional, Sobotková, M., additional, Čejková, B., additional, and Wassenaar, L. I., additional

Published
2012
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22. Expression of the bipolar see-saw in Antarctic climate records during the last deglaciation

Author

Stenni, B., primary, Buiron, D., additional, Frezzotti, M., additional, Albani, S., additional, Barbante, C., additional, Bard, E., additional, Barnola, J. M., additional, Baroni, M., additional, Baumgartner, M., additional, Bonazza, M., additional, Capron, E., additional, Castellano, E., additional, Chappellaz, J., additional, Delmonte, B., additional, Falourd, S., additional, Genoni, L., additional, Iacumin, P., additional, Jouzel, J., additional, Kipfstuhl, S., additional, Landais, A., additional, Lemieux-Dudon, B., additional, Maggi, V., additional, Masson-Delmotte, V., additional, Mazzola, C., additional, Minster, B., additional, Montagnat, M., additional, Mulvaney, R., additional, Narcisi, B., additional, Oerter, H., additional, Parrenin, F., additional, Petit, J. R., additional, Ritz, C., additional, Scarchilli, C., additional, Schilt, A., additional, Schüpbach, S., additional, Schwander, J., additional, Selmo, E., additional, Severi, M., additional, Stocker, T. F., additional, and Udisti, R., additional

Published
2010
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26. Technical Note: Evaluation of between-sample memory effects in the analysis of δ²H and δ18O of water samples measured by laser spectroscopes.

Author

Penna, D., Stenni, B., Šanda, M., Wrede, S., Bogaard, T. A., Michelini, M., Fischer, B. M. C., Gobbi, A., Mantese, N., Zuecco, G., Borga, M., Bonazza, M., Sobotková, M., Čejková, B., and Wassenaar, L. I.

Subjects
WATER sampling, LASER spectroscopy, STANDARD deviations, GEOLOGICAL surveys, HYDROGEN isotopes, OXYGEN isotopes
Abstract

This study evaluated between-sample memory in isotopic measurements of δ²H and δ18O in water samples by laser spectroscopy. Ten isotopically depleted water samples spanning a broad range of oxygen and hydrogen isotopic compositions were measured by three generations of off-axis integrated cavity output spectroscopy and cavity ring-down spectroscopy instruments. The analysis procedure encompassed small (less than 2‰ for δ²H and 1‰ for δ18O) and large (up to 201‰ for δ ²H and 25‰ for δ18O) differences in isotopic compositions between adjacent sample vials. Samples were injected 18 times each, and the between sample memory effect was quantified for each analysis run. Results showed that samples adversely affected by between sample isotopic differences stabilised after seven-eight injections. The between-sample memory effect ranged from 14% and 9% for δ²H and δ18O measurements, respectively, but declined to negligible carryover (between 0.1% and 0.3% for both isotopes) when the first ten injections of each sample were discarded. The measurement variability (range and standard deviation) was strongly dependent on the isotopic difference between adjacent vials. Standard deviations were up to 7.5‰for δ²H and 0.54‰for δ18O when all injections were retained in the computation of the reportable δ-value, but a significant increase in measurement precision (standard deviation in the range 0.1 ‰-1.0‰ for δ²H and 0.05‰- 0.17‰for δ18O) was obtained when the first eight injections were discarded. In conclusion, this study provided a practical solution to mitigate between-sample memory effects in the isotopic analysis of water samples by laser spectroscopy. [ABSTRACT FROM AUTHOR]

Published
2012
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27. Technical Note: On the memory effects in the analysis of δ²H and δ18O water samples measured by different laser spectroscopes.

Author

Penna, D., Stenni, B., Šanda, M., Wrede, S., Bogaard, T. A., Michelini, M., Fischer, B. M. C., Gobbi, A., Mantese, N., Borga, M., Bonazza, M., and Sobotková, M.

Abstract

This study focuses on the assessment of the practical implications of memory effects on the isotopic measurements of δ²H and δ18O in water samples analysed by means of laser spectroscopy. A set of ten depleted stable isotope samples featuring a broad range of isotopic compositions was measured by two Off-Axis Integrated Cavity Output Spectroscopy and two Cavity Ring-Down Spectroscopy instruments. The analysis scheme was set up to encompass both small (less than 2‰ for δ²H and 1‰ for δ18O) and large differences (up to 201‰ for δ²H and 25‰ for δ18O) in isotopic compositions between adjacent vials. All samples were injected 18 times for each analysis and the memory effect was computed for the entire run. Results showed that samples most affected by high inter-vial isotopic difference exhibited a tendency to stabilize after the first 7 or 8 injections, most likely as a result of memory effects during the run. These memory effects were quantified amounting to 14% and 9% of δ²H and δ18O measurements, respectively, with a decline to negligible values when first injections were discarded. The lowest percentages of memory effects were found for those instruments employing a long analysis time per injection, which most likely facilitated the removal of residual water molecules from the cavity. The measurement variability (range and standard deviation) for each sample was found to be strongly dependent on the isotopic differences between adjacent vials. A significant increase in measurement precision was obtained when injections most affected by memory effects were discarded from the computation of the reportable delta value. In conclusion, this study provides practical solutions to avoid or reduce the consequences of memory effects. [ABSTRACT FROM AUTHOR]

Published
2012
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28. On the reproducibility and repeatability of laser absorption spectroscopy measurements for δ2H and δ18O isotopic analysis.

Author

Penna, D., Stenni, B., Šanda, M., Wrede, S., Bogaard, T. A., Gobbi, A., Borga, M., Fischer, B. M. C., Bonazza, M., and Chárová, Z.

Abstract

The aim of this study was to analyse the reproducibility of off-axis integrated cavity output spectroscopy (OA-ICOS)-derived δ2H and δ18O measurements on a set of 35 water samples by comparing the performance of four laser spectroscopes with the performance of a conventional mass spectrometer under typical laboratory conditions. All samples were analysed using three different schemes of standard/sample combinations and related data processing to assess the improvement of results compared with mass spectrometry. The repeatability of the four OA-ICOS instruments was further investigated by multiple analyses of a sample subset to evaluate the stability of δ2H and δ18O measurements. Results demonstrated an overall agreement between OA-ICOS-based and mass spectrometry-based measurements for the entire dataset. However, a certain degree of variability existed in precision and accuracy between the four instruments. There was no evident bias or systematic deviations from the mass spectrometer values, but 15 random errors, which were apparently not related to external factors, significantly affected the final results. Our investigation revealed that analytical precision ranged from ±0.56‰ to 1.80‰ for δ2H and from ±0.10‰ to 0.27‰ for δ18O measurements, with a marked variability among the four instruments. The overall capability of laser instruments to reproduce stable results with repeated measurements of the same sample was acceptable, and there were general differences within the range of the analytical precision for each spectroscope. Hence, averaging the measurements of three identical samples led to a higher degree of accuracy and eliminated the potential for random deviations. [ABSTRACT FROM AUTHOR]

Published
2010
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30. Expression of the bipolar see-saw in Antarctic climate records during the last deglaciation

Author

Simon Schüpbach, Mélanie Baroni, Bénédicte Lemieux-Dudon, Robert Mulvaney, Amaelle Landais, Mirko Severi, Mattia Bonazza, Emilie Capron, J. R. Petit, Emiliano Castellano, Maurine Montagnat, Massimo Frezzotti, Valérie Masson-Delmotte, Valter Maggi, Biancamaria Narcisi, D. Buiron, J. M. Barnola, Roberto Udisti, Bénédicte Minster, Catherine Ritz, Matthias Baumgartner, Adrian Schilt, L. Genoni, Jérôme Chappellaz, Barbara Delmonte, Thomas F. Stocker, Frédéric Parrenin, Carlo Barbante, Hans Oerter, Paola Iacumin, E. Selmo, Jakob Schwander, Edouard Bard, Barbara Stenni, Sepp Kipfstuhl, Claudio Scarchilli, S. Falourd, Samuel Albani, Jean Jouzel, C. Mazzola, Dipartimento di Scienze Geologiche [Trieste], Università degli studi di Trieste, CLIPS, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Italian National agency for new technologies, Energy and sustainable economic development [Frascati] (ENEA), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Institute for the Dynamics of Environmental Processes-CNR, University of Ca’ Foscari [Venice, Italy], Environmental Sciences Department, Chaire Evolution du climat et de l'océan, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Department of Chemistry, Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Dipartimento di Scienze della Terra, University of Parma = Università degli studi di Parma [Parme, Italie], Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), EDGe, British Antarctic Survey (BAS), Natural Environment Research Council (NERC), European Project: 331615,EC:FP7:PEOPLE,FP7-PEOPLE-2012-IIF,TALDICE HOLOCENE(2013), Università degli studi di Trieste = University of Trieste, Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB), Collège de France - Chaire Evolution du climat et de l'océan, Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze = University of Florence (UniFI), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Parma = University of Parma (UNIPR), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS), University of Milano, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Università degli Studi di Firenze [Firenze], Università degli studi di Parma [Parme, Italie], Stenni, B., Buiron, D., Frezzotti, M., Albani, S., Barbante, C., Bard, E., Barnola, J. M., Baroni, M., Baumgartner, M., Bonazza, M., Capron, E., Castellano, E., Chappellaz, J., Delmonte, B., Falourd, S., Genoni, L., Iacumin, P., Jouzel, J., Kipfstuhl, S., Landais, A., Lemieux-Dudon, B., Maggi, V., Masson-Delmotte, V., Mazzola, C., Minster, B., Montagnat, M., Mulvaney, R., Narcisi, B., Oerter, H., Parrenin, F., Petit, J. R., Ritz, C., Scarchilli, C., Schilt, A., Schupbach, S., Schwander, J., Selmo, E., Severi, M., Stocker, T. F., Udisti, R., Stenni, Barbara, Baroni, C., Baumgartner, S., Bonazza, Mattia, Genoni, Laura, Kipfsthul, J., Lemieux Dudon, B., Masson Delmotte, V., Schüpbach, S., Stocker, T., Stenni, B, Buiron, D, Frezzotti, M, Albani, S, Barbante, C, Bard, E, Barnola, J, Baroni, M, Baumgartner, M, Bonazza, M, Capron, E, Castellano, E, Chappellaz, J, Delmonte, B, Falourd, S, Genoni, L, Iacumin, P, Jouzel, J, Kipfstuhl, S, Landais, A, Lemieux Dudon, B, Maggi, V, Masson Delmotte, V, Mazzola, C, Minster, B, Montagnat, M, Mulvaney, R, Narcisi, B, Oerter, H, Parrenin, F, Petit, J, Ritz, C, Scarchilli, C, Schilt, A, Schüpbach, S, Schwander, J, Selmo, E, Severi, M, Stocker, T, and Udisti, R

Subjects
Atlantic Sector, 010504 meteorology & atmospheric sciences, polar ice cores, methane synchronization, bipolar seesaw, last deglaciation, East Antarctica, Ross Sea, GEO/04 - GEOGRAFIA FISICA E GEOMORFOLOGIA, Greenland, polar ice core, temperature effect, deglaciation, 010502 geochemistry & geophysics, 01 natural sciences, palaeoclimate, palaeoceanography, Antarctic Cold Reversal, temporal record, Arctic, Ice cap climate, core analysis, Deglaciation, [SDU.STU.GL]Sciences of the Universe [physics]/Earth Sciences/Glaciology, Southern Ocean, Talos Dome, 0105 earth and related environmental sciences, Last Glacial, European Project for Ice Coring in Antarctica, Climate oscillation, Future sea level, Ice-sheet model, climate change, Oceanography, 13. Climate action, [SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology, Climatology, Abrupt climate change, Antarctica, General Earth and Planetary Sciences, stable isotopes, paleoclimate, ice cores, antarctica, ice core, Geology
Abstract

Ice-core records of climate from Greenland and Antarctica show asynchronous temperature variations on millennial timescales during the last glacial period 1 . The warming during the transition from glacial to interglacial conditions was markedly different between the hemispheres, a pattern attributed to the thermal bipolar see-saw 2 . However, a record from the Ross Sea sector of East Antarctica has been suggested to be synchronous with Northern Hemisphere climate change 3 . Here we present a temperature record from the Talos Dome ice core, also located in the Ross Sea sector. We compare our record with ice-core analyses from Greenland, based on methane synchronization 4 , and find clearly asynchronous temperature changes during the deglaciation. We also find distinct differences in Antarctic records, pointing to differences in the climate evolution of the Indo-Pacific and Atlantic sectors of Antarctica. In the Atlantic sector, we find that the rate of warming slowed between 16,000 and 14,500 years ago, parallel with the deceleration of the rise in atmospheric carbon dioxide concentrations and with a slight cooling over Greenland. In addition, our chronology supports the hypothesis that the cooling of the Antarctic Cold Reversal is synchronous with the Bolling‐Allerod warming in the northern hemisphere 14,700 years ago 5 . The period from about 8 to 25kyr before present (bp) includes the climate transition from the last glacial to the Holocene. As documented from polar ice cores and other climate archives, the pattern of climate changes throughout this transition is different between Antarctica and the surrounding Southern Ocean and the Northern Hemisphere. The steady Antarctic deglacial warming reaches a first maximum (Antarctic Isotopic Maximum AIM1; ref.1)followedbyaninterruptiontowardscoolerconditionsduring the Antarctic Cold Reversal (ACR). Conversely, Greenland records show two rapid-warming phases at the onset of the Dansgaard Oeschger-1(DO1)event(BllingAller dinterstadial,B/A)andthe

Published
2011
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31. Regional imprints of millennial variability during the MIS 3 period around Antarctica

Author

Didier Swingedouw, Matthias Baumgartner, Valérie Masson-Delmotte, Bénédicte Lemieux-Dudon, Amaelle Landais, Adrian Schilt, Mattia Bonazza, Emilie Capron, Barbara Stenni, Mirko Severi, Frédéric Parrenin, Massimo Frezzotti, Roberto Udisti, Masa Kageyama, D. Buiron, Jérôme Chappellaz, Enricomaria Selmo, Laboratoire de glaciologie et géophysique de l'environnement (LGGE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Dipartimento di Scienze Geologiche [Trieste], Università degli studi di Trieste, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Glaces et Continents, Climats et Isotopes Stables (GLACCIOS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), University of Bern, Italian National agency for new technologies, Energy and sustainable economic development [Frascati] (ENEA), Modélisation du climat (CLIM), Inria Grenoble - Rhône-Alpes, Institut National de Recherche en Informatique et en Automatique (Inria), Climate and Environmental Physics [Bern] (CEP), Physikalisches Institut [Bern], Universität Bern [Bern]-Universität Bern [Bern], University of Parma = Università degli studi di Parma [Parme, Italie], Università degli Studi di Firenze = University of Florence [Firenze] (UNIFI), Buiron, D., Stenni, Barbara, J., Chappellaz, A., Landai, M., Baumgartner, Bonazza, Mattia, E., Capron, M., Frezzotti, M., Kageyama, B., Lemieux Dudon, V., Masson Delmotte, F., Parrenin, A., Schilt, E., Selmo, M., Severi, D., Swingedouw, R., Udisti, Stenni, B., Chappellaz, J., Landais, A., Baumgartner, M., Bonazza, M., Capron, E., Frezzotti, M., Kageyama, M., Lemieux-Dudon, B., Masson-Delmotte, V., Parrenin, F., Schilt, A., Selmo, E., Severi, M., Swingedouw, D., Udisti, R., Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), Università degli studi di Trieste = University of Trieste, Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Universität Bern [Bern] (UNIBE)-Universität Bern [Bern] (UNIBE), Università degli studi di Parma = University of Parma (UNIPR), and Università degli Studi di Firenze = University of Florence (UniFI)

Subjects
Archeology, 010504 meteorology & atmospheric sciences, Paleoclimate, Global coupled model simulation, Greenland Ice Sheet, atmosphere-ocean coupling, Greenland, ice cores, 010502 geochemistry & geophysics, Oceanography, 01 natural sciences, Arctic, Ice core, Millennial-scale variability, Ice age, stable isotope, Cryosphere, Climate change, Glacial period, Dansgaard-Oeschger cycle, Indian Sector, Global coupled model, sodium, deuterium, Talos Dome, [SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere, Global and Planetary Change, geography.geographical_feature_category, teleconnection, Last Glacial, regional climate, Geology, Climatology, warming, millennial-scale variability, glacial period, global coupled model simulations, overturn, Paleoclimatology, freshwater input, paleoclimate, Paleoclimates, Southern Ocean, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Ecology, Evolution, Behavior and Systematics, 0105 earth and related environmental sciences, geography, Ice, marine isotope stage, East Antarctica, Arctic ice pack, Glacial geology, climate variation, Ice-sheet model, 13. Climate action, paleoceanography, coastal zone, meridional circulation, Antarctica, Ice sheet, ice core
Abstract

International audience; The climate of the last glacial Marine Isotopic Stage 3 (MIS3) period is characterized by strong millennial-scale variability with a succession of Dansgaard–Oeschger events first identified in Greenland ice cores and associated with variations of the Atlantic Meridional Overturning Circulation (AMOC). These abrupt events have a smooth and lagged counterpart in water stable isotopes from Antarctic ice cores. In this study we aim at depicting and understanding the circum-Antarctic expression of this millennial-scale variability. To illustrate the mechanisms potentially at work in the response of the southern high latitudes to an abrupt decrease of the AMOC, we first present results from experiments performed with the IPSL-CM4 atmosphere-ocean coupled model under glacial boundary conditions. When the AMOC is perturbed by imposing an additional freshwater flux in the North Atlantic, our model produces the classical bipolar seesaw mechanism generally invoked to explain the warming of the Southern Ocean/Antarctic region. However, this mechanism can be locally offset by faster atmospheric teleconnections originating from the tropics, even though the precise location of this fast response is not coherent among different climate models. Our model results are confronted with a synthesis of Antarctic records of ice core stable isotope and sea-salt sodium, including new data obtained on the TALDICE ice core. The IPSL-CM4 produces a dipole-like pattern around Antarctica, with warming in the Atlantic/Indian sectors contrasting with an unexpected cooling in the East-Pacific sector. The latter signal is not detected in our data synthesis. Both ice core data and simulations are consistent in depicting a more rapid response of the Atlantic sector compared to the Indian sector. This feature can be explained by the gradual impact of ocean transport on which faster atmospheric teleconnections are superimposed. Detailed investigations of the sequence of events between different proxies are conducted in three ice cores. Earlier shifts in deuterium excess and significant changes in sea-salt sodium fluxes in the most coastal sites (TALDICE and EDML) compared to EDC suggest reorganizations in local moisture sources, possibly linked with sea-ice cover. This study demonstrates the added value of circum-Antarctic ice core records to characterize the patterns and mechanisms of glacial climate variability.

Published
2012
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32. Sampling procedures for inventory of commercial volume tree species in Amazon Forest.

Author

Netto SP, Pelissari AL, Cysneiros VC, Bonazza M, and Sanquetta CR

Subjects
Cluster Analysis, Models, Theoretical, Spatial Analysis, Species Specificity, Tropical Climate, Biodiversity, Environmental Monitoring, Trees classification
Abstract

The spatial distribution of tropical tree species can affect the consistency of the estimators in commercial forest inventories, therefore, appropriate sampling procedures are required to survey species with different spatial patterns in the Amazon Forest. For this, the present study aims to evaluate the conventional sampling procedures and introduce the adaptive cluster sampling for volumetric inventories of Amazonian tree species, considering the hypotheses that the density, the spatial distribution and the zero-plots affect the consistency of the estimators, and that the adaptive cluster sampling allows to obtain more accurate volumetric estimation. We use data from a census carried out in Jamari National Forest, Brazil, where trees with diameters equal to or higher than 40 cm were measured in 1,355 plots. Species with different spatial patterns were selected and sampled with simple random sampling, systematic sampling, linear cluster sampling and adaptive cluster sampling, whereby the accuracy of the volumetric estimation and presence of zero-plots were evaluated. The sampling procedures applied to species were affected by the low density of trees and the large number of zero-plots, wherein the adaptive clusters allowed concentrating the sampling effort in plots with trees and, thus, agglutinating more representative samples to estimate the commercial volume.

Published
2017
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33. Simpler, faster, more accurate melanocytic lesion segmentation through MEDS.

Author

Peruch F, Bogo F, Bonazza M, Cappelleri VM, and Peserico E

Subjects
Humans, Principal Component Analysis, Dermoscopy methods, Image Processing, Computer-Assisted methods, Melanoma pathology, Skin Neoplasms pathology
Abstract

We present a new technique for melanocytic lesion segmentation, Mimicking Expert Dermatologists' Segmentations (MEDS), and extensive tests of its accuracy, speed, and robustness. MEDS combines a thresholding scheme reproducing the cognitive process of dermatologists with a number of optimizations that may be of independent interest. MEDS is simple, with a single parameter tuning its “tightness”. It is extremely fast, segmenting medium-resolution images in a fraction of a second even with the modest computational resources of a cell phone-an improvement of an order of magnitude or more over state-of-the-art techniques. And it is extremely accurate: very experienced dermatologists disagree with its segmentations less than they disagree with the segmentations of state-of-the-art techniques, and in fact less than they disagree with the segmentations of dermatologists of moderate experience.

Published
2014
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34. [Morphological variations of the temporomandibular joint. Statistical studies on its anatomical features].

Author

Capurso U and Bonazza M

Subjects
Adult, Aging, Cephalometry, Female, Humans, Male, Mandibular Condyle anatomy & histology, Odontometry, Reference Values, Sex Characteristics, Temporomandibular Joint anatomy & histology
Abstract

Data regarding the joints, skeleton and teeth, including specific measurements of condylar diameters, the height of mandibular branches and the gonial angle, were obtained from the study of 100 dry skulls from young adults of both sexes. An innovative measurement technique was required to assess the articular eminence, whereas Yale's scale and Scott's method were used to analyse condylar morphology and dental wear (attrition) respectively. The presence of elementary, uni- and bilateral joint lesions and adaptive remodelling was also assessed. Special attention was paid to the examination of possible asymmetries, which proved to be numerous, due to the supposed repercussions on mandibular arthrokinematics. The correlation between condylar alterations and the various bone and dental parameters was not significant, except in the presence of third class bone or cross bites. The sample population in question, which possessed abundant dental remains, proved to be relatively homogeneous and well distributed in terms of sex and age; it may therefore be used as a reference population for the assessment of temporomandibular morphology.

Published
1990

35. The significance of measurement of several oncofetal antigens in diagnosis and management of epithelial ovarian tumors.

Author

Massi GB, Amunni G, Tommasi M, Bonazza M, Ciardetti P, and Cappelli G

Subjects
Adenocarcinoma diagnosis, Adenocarcinoma, Mucinous diagnosis, Adult, Aged, Chorionic Gonadotropin, beta Subunit, Human, Cystadenocarcinoma diagnosis, Endometriosis diagnosis, Female, Follow-Up Studies, Humans, Mesonephroma diagnosis, Middle Aged, Ovarian Neoplasms therapy, Carcinoembryonic Antigen analysis, Chorionic Gonadotropin blood, Ferritins blood, Ovarian Neoplasms diagnosis, Peptide Fragments blood, alpha-Fetoproteins analysis
Abstract

Association of serum alphafetoprotein (alpha FP), human chorionic gonadotropin beta-subunit (beta-HCG), carcinoembryonic antigen (CEA) and ferritin (FER) was studied in a group of 72 patients with epithelial ovarian cancer 15 days after surgery and at various times during 2 years. Only CEA and ferritin are able to reflect tumor burden in detecting evolutive disease; alpha FP and beta-HCG have a diagnostic significance in few cases, probably related to a particular, not evident, histological component of the tumor. Nevertheless the data indicate that the use of marker association can improve our capacity to detect, overall in the residual and evolutive disease, the real clinical burden of the patients.

Published
1983

36. Ferritinemia in ovarian malignant tumours.

Author

Bonazza M, Amunni G, Tommasi M, Fiscella A, Cappelli G, Ciardetti P, and Massi GB

Subjects
Adenocarcinoma blood, Adenocarcinoma, Mucinous blood, Carcinoma blood, Endometriosis blood, Female, Follow-Up Studies, Humans, Iron blood, Mesonephroma blood, Neoplasm Staging, Ovarian Neoplasms drug therapy, Ovarian Neoplasms surgery, Radioimmunoassay, Ferritins blood, Ovarian Neoplasms blood
Abstract

Seriated ferritin assays were carried out on 95 patients affected by primitive ovarian epithelial tumour over a period of three years (1979/82), by radioimmunometric assay for human spleen ferritin. Ferritin was elevated in endometrioid tumours and in the presence of active progressing disease and chemotherapy did not influence these values. The ferritin/sideremia ratio was high in the case with pathological levels. Studying the glicosilation of this protein a significant amount of ferritin was not bound to concavallin A, suggesting direct release of this protein by tumour cells.

Published
1983

37. Monoclonal antibodies in serological, immunoscintigraphic and immunocytochemical diagnosis of epithelial ovarian cancer.

Author

Branconi F, Amunni G, Bonazza M, Villanucci A, Veneziano AE, and Massi GB

Subjects
Antigens, Tumor-Associated, Carbohydrate analysis, Carcinoma diagnostic imaging, Carcinoma surgery, Female, Follow-Up Studies, Humans, Neoplasm Staging, Ovarian Neoplasms blood, Ovarian Neoplasms diagnostic imaging, Ovarian Neoplasms surgery, Radiography, Remission Induction, Antibodies, Monoclonal, Carcinoma diagnosis, Ovarian Neoplasms diagnosis
Abstract

In present work the Authors examine the utility of CA 125 assay in patients affected by epithelial ovarian cancer. It is stressed that marker negativity does not necessarily imply the absence of disease. On the other hand the Authors underly the almost total absence of false positives, the only problem being with cases of benign gynaecological pathologies. The CA 125 assay appears to provide informations in the evaluation of response to therapy. Finally they note two more recent applications of monoclonal antibodies: first, marking these substances with radioisotopes; second, immunohistochemistry that shows the presence and location of the antigen at the histological level. (By editorial staff).

Published
1989

38. [Pelvic inflammatory disease and the intrauterine device].

Author

Bonazza M, Amunni G, Ciardetti P, Lazzerini E, and Massi GB

Subjects
Disease, Family Planning Services, Infections, Research, Research Design, Contraception, Incidence, Intrauterine Devices, Pelvic Inflammatory Disease
Published
1981

39. Polychemotherapy in ovarian cancer: treatment with Adriamycin, BCNU and cyclophosphamide vs. Adriamycin and cyclophosphamide.

Author

Mazzei T, Bonazza M, Amunni G, Scarselli G, Branconi F, and Massi GB

Subjects
Adenocarcinoma drug therapy, Adenocarcinoma surgery, Adult, Aged, Carcinoma surgery, Carmustine administration & dosage, Combined Modality Therapy, Cyclophosphamide administration & dosage, Cystadenoma surgery, Doxorubicin administration & dosage, Female, Humans, Middle Aged, Ovarian Neoplasms surgery, Antineoplastic Combined Chemotherapy Protocols therapeutic use, Carcinoma drug therapy, Cystadenoma drug therapy, Ovarian Neoplasms drug therapy
Abstract

The authors compared both therapeutic efficacy and toxicity of two different treatment regimens: ABC = adriamycin, nitrogen mustard (BCNU) and cyclophosphamide (CTX) vs. AC = adriamycin and cyclophosphamide in ovarian cancer. Thirty-one patients were entered under treatment plan ABC and 26 under treatment plan AC simultaneously. Therapeutic evaluation was subdivided into different risk groups (adjuvant therapy, residual disease less than or greater than 2 cm). A similar result could be noted in the two different treatment regimens. Toxicity was more severe and frequent in the group treated with BCNU. The AC regimen was preferred because of its lower incidence of side-effects and for its easier mode of administration.

Published
1984

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