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1. SISALv2: A comprehensive speleothem isotope database with multiple age-depth models

Author

Comas-Bru, L, Rehfeld, K, Roesch, C, Amirnezhad-Mozhdehi, S, Harrison, SP, Atsawawaranunt, K, Ahmad, SM, Brahim, YA, Baker, A, Bosomworth, M, Breitenbach, SFM, Burstyn, Y, Columbu, A, Deininger, M, Demény, A, Dixon, B, Fohlmeister, J, Hatvani, IG, Hu, J, Kaushal, N, Kern, Z, Labuhn, I, Lechleitner, FA, Lorrey, A, Martrat, B, Novello, VF, Oster, J, Pérez-Mejías, C, Scholz, D, Scroxton, N, Sinha, N, Ward, BM, Warken, S, Zhang, H, Apaéstegui, J, Baldini, LM, Band, S, Blaauw, M, Boch, R, Borsato, A, Budsky, A, Rosell, MGB, Chawchai, S, Constantin, S, Denniston, R, Dragusin, V, Drysdale, R, Dumitru, O, Frappier, A, Gandhi, N, Gautam, P, Hanying, L, Isola, I, Jiang, X, Jingyao, Z, Johnson, K, Vanessa Johnston, Kathayat, G, Klose, J, Krause, C, Lachniet, M, Laskar, A, Lauritzen, SE, Lončar, N, Moseley, G, Narayana, AC, Onac, BP, Racovitǎ, E, Pawlak, J, Ramsey, CB, Rivera-Collazo, I, Rossi, C, Rowe, PJ, Stríkis, NM, Tan, L, Verheyden, S, Vonhof, H, Weber, M, Wendt, K, Wilcox, P, Winter, A, Wu, J, Wynn, P, and Yadava, MG

Subjects
Atmospheric Sciences, Geochemistry, Physical Geography and Environmental Geoscience
Abstract

Characterizing the temporal uncertainty in palaeoclimate records is crucial for analysing past climate change, correlating climate events between records, assessing climate periodicities, identifying potential triggers and evaluating climate model simulations. The first global compilation of speleothem isotope records by the SISAL (Speleothem Isotope Synthesis and Analysis) working group showed that age model uncertainties are not systematically reported in the published literature, and these are only available for a limited number of records (ca. 15 %, n = 107/691). To improve the usefulness of the SISAL database, we have (i) improved the database's spatio-temporal coverage and (ii) created new chronologies using seven different approaches for age- depth modelling. We have applied these alternative chronologies to the records from the first version of the SISAL database (SISALv1) and to new records compiled since the release of SISALv1. This paper documents the necessary changes in the structure of the SISAL database to accommodate the inclusion of the new age models and their uncertainties as well as the expansion of the database to include new records and the qualitycontrol measures applied. This paper also documents the age-depth model approaches used to calculate the new chronologies. The updated version of the SISAL database (SISALv2) contains isotopic data from 691 speleothem records from 294 cave sites and new age-depth models, including age-depth temporal uncertainties for 512 speleothems.

Published
2020

4. Time-resolved diffuse reflectance studies of beta-phenyl ketones in the solid state: conformational and chiral control of triplet lifetimes

Author

Boch, R., Bohne, C., and Scaiano, J.C.

Subjects
Ketones -- Research, Excited state chemistry -- Research, Biological sciences, Chemistry
Abstract

The effect of conformational changes on triplet lifetimes of beta-aryl ketones has been investigated by laser flash diffuse reflectance photolysis. The results showed that the triplet states decay in solution by a charge transfer interaction between the aryl group and the excited carbonyl. The conformational interaction was also found to affect the compounds in the solid state.

Published
1996

5. Geochemistry of Vein Calcites Hosted in the Troodos Pillow Lavas and Their Implications for the Timing and Physicochemical Environment of Fracturing, Fluid Circulation, and Vein Mineral Growth

Author

Quandt, D., Micheuz, P., Kurz, W., Kluge, T., Boch, R., Hippler, D., Krenn, K., and Hauzenberger, C.A.

Subjects
Isotopic Composition and Chemistry, Stable Isotope Geochemistry, Major and Trace Element Geochemistry, Radiogenic Isotope Geochemistry, Geography & travel, Stable Isotopes, Volcanology, Calcite veins, Ophiolites, Hydrothermal Systems, Marine Geology and Geophysics, Biogeosciences, Oceanography: Biological and Chemical, Geochemistry, Tectonophysics, Clumped Isotope Geochemistry: From Theory to Applications, Fluid circulation, Troodos ophiolite, Research Articles, Mineralogy and Petrology, Research Article, ddc:910
Abstract

Calcite veins hosted in pillow lavas of the Late Cretaceous Troodos suprasubduction zone ophiolite provide insights into the timing and physicochemical environment of postmagmatic fracturing and fluid circulation through oceanic crust. This study presents rare earth element and yttrium (REE+Y) concentrations, δ13C, δ18O, 87Sr/86Sr, and clumped isotopic (Δ47) compositions of vein calcites in order to investigate their fluid sources, formation temperatures, and precipitation ages. These geochemical data are combined with microtextural analyses. Intersections of 87Sr/86Sr ratios of vein calcites with the Sr isotope seawater curve suggest two distinct calcite veining phases. Major calcite veining within an interval of ~10 Myr after crust formation is characterized by microtextures that point to extensional fracturing related to crack and sealing, host rock brecciation, and advective fluid flow. These vein calcites show REE+Y characteristics, 87Sr/86Sr ratios, and clumped isotopic compositions indicative of precipitation from seawater at, Key Points The Troodos oceanic crust experienced a 10‐Myr‐long major phase of predominantly low‐temperature blocky and syntaxial calcite veiningOscillatory growth‐zoned high‐temperature blocky vein calcites precipitated from hydrothermal fluids in a closed system out of equilibriumLow‐temperature diffusion‐fed antitaxial vein calcites precipitated after the major veining phase from seawater that interacted with umbers

Published
2019

6. The SISAL database: A global resource to document oxygen and carbon isotope records from speleothems

Author

Atsawawaranunt, K, Comas-Bru, L, Amirnezhad Mozhdehi, S, Deininger, M, Harrison, SP, Baker, A, Boyd, M, Kaushal, N, Masood Ahmad, S, Ait Brahim, Y, Arienzo, M, Bajo, P, Braun, K, Burstyn, Y, Chawchai, S, Duan, W, Hatvani, IG, Hu, J, Kern, Z, Labuhn, I, Lachniet, M, Lechleitner, FA, Lorrey, A, Pérez-Mejías, C, Pickering, R, Scroxton, N, Atkinson, T, Ayalon, A, Baldini, J, Bar-Matthews, M, Bernal, JP, Breitenbach, S, Boch, R, Borsato, A, Cai, Y, Carolin, S, Cheng, H, Columbu, A, Couchoid, I, Cruz, F, Demény, A, Dominguez-Villar, D, Drăgusin, V, Drysdale, R, Ersek, V, Finné, M, Fleitmann, D, Fohlmeister, J, Frappier, A, Genty, D, Holzkämper, S, Hopley, P, Kathayat, G, Keenan-Jones, D, Koltai, G, Luetscher, M, Li, TY, Lone, MA, Markowska, M, Mattey, D, McDermott, F, Moreno, A, Moseley, G, Nehme, C, Novello, VF, Psomiadis, D, Rehfeld, K, Ruan, J, Sekhon, N, Sha, L, Sholz, D, Shopov, Y, Smith, A, Strikis, N, Treble, P, Vaks, A, Vansteenberge, S, Veiga-Pires, C, Voarintsoa, NR, Wang, X, Wong, C, Wortham, B, Wurtzel, J, Zong, B, Atsawawaranunt, K, Comas-Bru, L, Amirnezhad Mozhdehi, S, Deininger, M, Harrison, SP, Baker, A, Boyd, M, Kaushal, N, Masood Ahmad, S, Ait Brahim, Y, Arienzo, M, Bajo, P, Braun, K, Burstyn, Y, Chawchai, S, Duan, W, Hatvani, IG, Hu, J, Kern, Z, Labuhn, I, Lachniet, M, Lechleitner, FA, Lorrey, A, Pérez-Mejías, C, Pickering, R, Scroxton, N, Atkinson, T, Ayalon, A, Baldini, J, Bar-Matthews, M, Bernal, JP, Breitenbach, S, Boch, R, Borsato, A, Cai, Y, Carolin, S, Cheng, H, Columbu, A, Couchoid, I, Cruz, F, Demény, A, Dominguez-Villar, D, Drăgusin, V, Drysdale, R, Ersek, V, Finné, M, Fleitmann, D, Fohlmeister, J, Frappier, A, Genty, D, Holzkämper, S, Hopley, P, Kathayat, G, Keenan-Jones, D, Koltai, G, Luetscher, M, Li, TY, Lone, MA, Markowska, M, Mattey, D, McDermott, F, Moreno, A, Moseley, G, Nehme, C, Novello, VF, Psomiadis, D, Rehfeld, K, Ruan, J, Sekhon, N, Sha, L, Sholz, D, Shopov, Y, Smith, A, Strikis, N, Treble, P, Vaks, A, Vansteenberge, S, Veiga-Pires, C, Voarintsoa, NR, Wang, X, Wong, C, Wortham, B, Wurtzel, J, and Zong, B

Abstract

Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide out-of-sample evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (18O, 13C) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data. The compiled data are available at

Published
2018

40. 2-Heptanone and 10-hydroxy- trans-dec-2-enoic acid in the mandibular glands of worker honey bees of different ages.

Author

Boch, R. and Shearer, D.

Abstract

Copyright of Zeitschrift für Vergleichende Physiologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
1967
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41. Participation of prefrontal neurons in the preparation of visually guided eye movements in the rhesus monkey.

Author

Boch, R A and Goldberg, M E

Abstract

1. We recorded from 257 neurons in the banks of the posterior third of the principal sulcus of two rhesus monkeys trained to look at a fixation point and make saccades to stimuli in the visual periphery. Sixty-six percent (220/257) discharged or were suppressed in association with one or more aspects of the tasks we used. 2. Fifty-eight percent (151/257) of the neurons responded to the appearance of a spot of light in some part of the contralateral visual field. Cells did not seem to have absolute requirements for stimulus shape, size, or direction of motion. 3. Thirty-six percent (29/79) of visually responsive neurons tested quantitatively gave an enhanced response to the stimulus in the receptive field when the monkey had to make a saccade to the stimulus when its appearance was synchronous with the disappearance of the fixation point (synchron task). Twenty-nine percent (19/57) of the neurons gave an enhanced response to the stimulus when the monkey had to make a saccade to the stimulus some time after it appeared (delayed-saccade task). In general, enhancement in the synchron task correlated well with enhancement in the delayed-saccade task. 4. Enhancement was spatially specific. It did not occur when the monkey made a saccade to a stimulus outside the receptive field even though there was a stimulus within the receptive field. 5. Twenty-three percent (27/117) of neurons studied in the delayed-saccade task gave two bursts, one at the appearance of the stimulus and a second one around the saccade. This second burst generally did not occur when the monkey made the same saccade to a remembered target, but instead required the presence of the visual stimulus, and so we describe it as a reactivation of the visual response. Reactivation was also spatially specific. 6. The latency from reactivation to the beginning of the saccade ranged from 160 ms before the saccade to the beginning of the saccade. Reactivation usually continued for several hundred milliseconds after the saccade, sometimes for the duration of the trial. 7. Reactivation and enhancement are not the same mechanism. Although some cells showed both phenomena there was no correlation between enhancement and reactivation. 8. Cells that showed reactivation in the saccade task also showed reactivation at a weaker level in a suppressed-saccade task. In this task the monkeys had to hold fixation despite the disappearance of the fixation point and the continued presence of the peripheral stimulus.(ABSTRACT TRUNCATED AT 400 WORDS)

Published
1989

42. 32×32 planar IR photovoltaic mosaic arrays on sputtered CdxHg1-xTe epilayers.

Author

Roussille, R., Amingual, D., Boch, R., Destefanis, G. L., and Tissot, J. L.

Subjects
MERCURY cadmium tellurides, SPUTTERING (Physics), EPITAXY, HALL effect, MATHEMATICAL models
Abstract

Epitaxial n-type CdxHg1-xTe layers on (111) CdTe substrates have been grown between 250 and 300 °C by sputtering deposition. The standard growth rate was nominally 2 μm/h for a thickness range from 10 to 30 μm. Typical electron concentration in CdxHg1-xTe layers with Cd composition of 0.34 is around of 2×1016 cm-3 with a Hall mobility of 20 000 cm2 V-1 s-1 at 77 K. Films can be converted to p type after annealing. We report for the first time the characteristics of backside illuminated 32×32 planar photovoltaic mosaic arrays processed on sputtered layers. Hybrid structures have been fabricated and evaluated; the preliminary results indicate the suitability of these mosaics for hybrid focal plane applications. [ABSTRACT FROM AUTHOR]

Published
1984
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