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1. OTOLITH MICROCHEMISTRY INDICATES UNEXPECTED PATTERNS OF RESIDENCY AND ANADROMY IN BLUEBACK HERRING, ALOSA AESTIVALIS, IN THE HUDSON AND MOHAWK RIVERS.

Author

LIMBURG K. E., BLACKBURN I., SCHMIDT R., LAKE T., HASSE J., ELFMAN M., and KRISTIANSSON P.

Subjects
Alosa aestivalis, landlocking, otolith microchemistry, environmental history, Aquaculture. Fisheries. Angling, SH1-691
Abstract

Blueback herring is an anadromous fish endemic in the tidal Hudson River Estuary, USA. Twentieth-century improvements to a lock and canal system permitted the species to invade the Hudson’s main tributary, the Mohawk River, where it has been recorded since the 1930s. Moving westward over time, individuals were collected in Lake Ontario, approx. 275 km west of the Hudson, in 1997. However, the actual status (resident or marine anadromous) of adults there or in the Mohawk has not been determined. We collected adult blueback herring in the spring 1999 spawning run and analyzed their otoliths’ elemental composition with both electron (WDS) and nuclear (mu PIXE) microprobes. We measured strontium:calcium ratios along « life-history transects » (WDS) and mapped entire otoliths (mu PIXE), providing a detailed time series of data on the Sr:Ca, and thus habitat use history, of the fish. We also analyzed otoliths of Mohawk and Hudson River young-of-year (YOY). The Sr:Ca ratios of Mohawk YOY are slightly but significantly higher than those of Hudson YOY. Life history transects for 51 adults show complex patterns of Sr:Ca, indicating that many of the fish move into salt water at least for brief periods. However, many fish appear to spend extended parts of their post-YOY lives in fresh water, and at least two adults (caught in the Mohawk near Rome, NY) appear never to have changed habitats at all. This is thus the first demonstration of residency in Mohawk River herring.

Published
2001
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3. Response of a Li-glass/multi-anode photomultiplier detector to focused proton and deuteron beams

Author

Rofors, E., Pallon, J., Jebali, R. Al, Annand, J. R. M., Boyd, L., Christensen, M. J., Clemens, U., Desert, S., Elfman, M., Engels, R., Fissum, K. G., Frielinghaus, H., Frost, R., Gardner, S., Gheorghe, C., Hall-Wilton, R., Jaksch, S., Kanaki, K., Kemmerling, G., Kristiansson, P., Livingston, K., Maulerova, V., Mauritzson, N., Montgomery, R., Perrey, H., Richter, T., Scherzinger, J., Seitz, B., and Shetty, M.

Subjects
Physics - Instrumentation and Detectors, Nuclear Experiment
Abstract

The response of a position-sensitive Li-glass based scintillation detector to focused beams of 2.5 MeV protons and deuterons has been investigated. The beams were scanned across the detector in 0.5 mm horizontal and vertical steps perpendicular to the beams. Scintillation light was registered using an 8 by 8 pixel multi-anode photomultiplier tube. The signal amplitudes were recorded for each pixel on an event-by-event basis. Several pixels generally registered considerable signals at each beam location. The number of pixels above set thresholds were investigated, with the optimization of the single-hit efficiency over the largest possible area as the goal. For both beams, at a threshold of ~50% of the mean of the full-deposition peak, ~80% of the events were registered in a single pixel, resulting in an effective position resolution of ~5 mm in X and Y., Comment: 22 pages, 8 figures, to be submitted to Nucl. Instr. and Meth. in Phys. Res. A

Published
2020
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6. Preliminary results from a study of luminescent materials : For application in the beam imaging system at the ESS

Author

Frost, Robert J. W., Thomas, C. A., Elfman, M., Johansson, R., Hartl, M., Kocevar, H., Michel, K., Joshi, S., Björklund, S., Frost, Robert J. W., Thomas, C. A., Elfman, M., Johansson, R., Hartl, M., Kocevar, H., Michel, K., Joshi, S., and Björklund, S.

Abstract

As part of the development of the beam imaging system at the European Spallation Source, luminescent screens have been fabricated by the flame spraying of scintillating materials onto stainless steel backings. A total of seven screens were produced, three of chromia alumina (Al2O3:Cr), two of YAG (Y3Al5O12:Ce) and two of a 50/50 mix of these. The properties of these screens under proton irradiation were evaluated using a 2.55 MeV proton beam at currents of up to 10 A. Irradiation times were up to 25 h per sample, during which luminescence-, spectrographic-, thermal- and current-data was sampled at a rate of 1 Hz. Preliminary results of these measurements are reported here; with a quantitative analysis presented for one of the chromia alumina screens and a qualitative comparison of all three material types. The luminescent yield for chromia alumina was determined to be around 2000 photons/MeV for a virgin screen, and was found to drop to 1.5% after 167 mC of proton irradiation. A recovery of the luminescence of chromia alumina to >60% was observed after beam current was reduced for an 8 h period. Observations indicate that the YAG and mixed composition screens retain higher luminescence than the chromia alumina even at temperatures of over 200 °C. It is indicated that the luminescence from YAG feeds the R-lines of chromia alumina in the mixed composition screens.

Published
2023
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15. Globally distributed iridium layer preserved within the Chicxulub impact structure

Author

Goderis, S., Sato, H., Ferrière, L., Schmitz, B., Burney, D., Kaskes, P., Vellekoop, J., Wittmann, A., Schulz, T., Chernonozhkin, S.M., Claeys, P., de Graaff, S.J., Déhais, T., de Winter, N.J., Elfman, M., Feignon, J.-G., Ishikawa, A., Koeberl, C., Kristiansson, P., Neal, C.R., Owens, J.D., Schmieder, M., Sinnesael, M., Vanhaecke, F., van Malderen, S.J.M., Bralower, T.J., Gulick, S.P.S., Kring, D.A., Lowery, C.M., Morgan, J.V., Smit, J., Whalen, M.T., Goderis, S., Sato, H., Ferrière, L., Schmitz, B., Burney, D., Kaskes, P., Vellekoop, J., Wittmann, A., Schulz, T., Chernonozhkin, S.M., Claeys, P., de Graaff, S.J., Déhais, T., de Winter, N.J., Elfman, M., Feignon, J.-G., Ishikawa, A., Koeberl, C., Kristiansson, P., Neal, C.R., Owens, J.D., Schmieder, M., Sinnesael, M., Vanhaecke, F., van Malderen, S.J.M., Bralower, T.J., Gulick, S.P.S., Kring, D.A., Lowery, C.M., Morgan, J.V., Smit, J., and Whalen, M.T.

Abstract

The Cretaceous-Paleogene (K-Pg) mass extinction is marked globally by elevated concentrations of iridium, emplaced by a hypervelocity impact event 66 million years ago. Here, we report new data from four independent laboratories that reveal a positive iridium anomaly within the peak-ring sequence of the Chicxulub impact structure, in drill core recovered by IODP-ICDP Expedition 364. The highest concentration of ultrafine meteoritic matter occurs in the post-impact sediments that cover the crater peak ring, just below the lowermost Danian pelagic limestone. Within years to decades after the impact event, this part of the Chicxulub impact basin returned to a relatively low-energy depositional environment, recording in unprecedented detail the recovery of life during the succeeding millennia. The iridium layer provides a key temporal horizon precisely linking Chicxulub to K-Pg boundary sections worldwide.

Published
2021

16. Globally distributed iridium layer preserved within the Chicxulub impact structure

Author

Stratigraphy and paleontology, Stratigraphy & paleontology, Goderis, S., Sato, H., Ferrière, L., Schmitz, B., Burney, D., Kaskes, P., Vellekoop, J., Wittmann, A., Schulz, T., Chernonozhkin, S.M., Claeys, P., de Graaff, S.J., Déhais, T., de Winter, N.J., Elfman, M., Feignon, J.-G., Ishikawa, A., Koeberl, C., Kristiansson, P., Neal, C.R., Owens, J.D., Schmieder, M., Sinnesael, M., Vanhaecke, F., van Malderen, S.J.M., Bralower, T.J., Gulick, S.P.S., Kring, D.A., Lowery, C.M., Morgan, J.V., Smit, J., Whalen, M.T., Stratigraphy and paleontology, Stratigraphy & paleontology, Goderis, S., Sato, H., Ferrière, L., Schmitz, B., Burney, D., Kaskes, P., Vellekoop, J., Wittmann, A., Schulz, T., Chernonozhkin, S.M., Claeys, P., de Graaff, S.J., Déhais, T., de Winter, N.J., Elfman, M., Feignon, J.-G., Ishikawa, A., Koeberl, C., Kristiansson, P., Neal, C.R., Owens, J.D., Schmieder, M., Sinnesael, M., Vanhaecke, F., van Malderen, S.J.M., Bralower, T.J., Gulick, S.P.S., Kring, D.A., Lowery, C.M., Morgan, J.V., Smit, J., and Whalen, M.T.

Published
2021

19. Response of a Li-glass/multi-anode photomultiplier detector to focused proton and deuteron beams

Author

Rofors, E., primary, Pallon, J., additional, Al Jebali, R., additional, Annand, J.R.M., additional, Boyd, L., additional, Christensen, M.J., additional, Clemens, U., additional, Desert, S., additional, Elfman, M., additional, Engels, R., additional, Fissum, K.G., additional, Frielinghaus, H., additional, Frost, R., additional, Gardner, S., additional, Gheorghe, C., additional, Hall-Wilton, R., additional, Jaksch, S., additional, Kanaki, K., additional, Kemmerling, G., additional, Kristiansson, P., additional, Livingston, K., additional, Maulerova, V., additional, Mauritzson, N., additional, Montgomery, R., additional, Perrey, H., additional, Richter, T., additional, Scherzinger, J., additional, Seitz, B., additional, and Shetty, M., additional

Published
2020
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29. Insights from two-dimensional mapping of otolith chemistry.

Author

Limburg, K. E. and Elfman, M.

Subjects
*OTOLITH organs, *MICROCHEMISTRY, *CLASSIFICATION of fish, *SYNCHROTRONS, *CRYSTALLIZATION
Abstract

Non-destructive microbeam-based methods were used for 2-D mapping of trace elements to gain a greater appreciation of otolith composition and spatial configuration. Based on studies of a wide variety of fish taxa, this approach more fully captures the nature of otolith chemical heterogeneity. Such variations may be due to a number of factors, including differences in crystallization, genetics, growth or even sample preparation or contamination. Examples presented here highlight research conducted at the Lund Ion Beam Analysis Facility (LIBAF) and at the Cornell High-Energy Synchrotron Source (CHESS). [ABSTRACT FROM AUTHOR]

Published
2017
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40. Scanning mu-RBS characterisation of local loading effects of non-selectively epitaxially grown SiGe thin films

Author

Winzell, T., Pejnefors, J., Elfman, M., Östling, Mikael, Whitlow, H. J., Winzell, T., Pejnefors, J., Elfman, M., Östling, Mikael, and Whitlow, H. J.

Abstract

Scanning microbeam Rutherford backscattering spectrometry (mu -RBS) has been employed to investigate local loading effects of non-selective epitaxial growth (NSEG) of SiGe on Si in structures consisting of apertures in an SiO2 mask. The structure sizes were 22 mum x 22 mum. 42 mum x 42 mum, 82 mum x 82 mum and 500 mum x 2000 mum. From the measured thickness and Ge content, it was concluded that in NSEG local loading effects for the structure sizes used are small or absent., QC 20100525

Published
2001
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42. SCIENTISTS AND ARTISTS: "HEY! YOU GOT ART IN MY SCIENCE! YOU GOT SCIENCE ON MY ART.".

Author

Elfman, M. E., Hayes, B., Boyer, B., and Michel, K.

Subjects
SCIENTISTS, ARTISTS, COMPUTER-generated imagery, COMPUTER graphics, SUPERCOMPUTERS
Abstract

The pairing of science and art has proven to be a powerful combination since the Renaissance. The combination of these two seemingly disparate disciplines ensured that even complex scientific theories could be explored and effectively communicated to both the subject matter expert and the layman. In modern times, science and art have frequently been considered disjoint, with objectives, philosophies, and perspectives often in direct opposition to each other. However, given the technological advances in computer science and high fidelity 3-D graphics development tools, this marriage of art and science is once again logically complimentary. Art, in the form of computer graphics and animation created on supercomputers, has already proven to be a powerful tool for improving scientific research and providing insight into nuclear phenomena. This paper discusses the power of pairing artists with scientists and engineers in order to pursue the possibilities of a widely accessible lightweight, interactive approach. We will use a discussion of photo-realism versus stylization to illuminate the expected beneficial outcome of such collaborations and the societal advantages gained by a non-traditional partnering of these two fields. [ABSTRACT FROM AUTHOR]

Published
2010

43. Optical dot gain on newsprint determined with the Lund nuclear microprobe

Author

Kristiansson, P., Nilsson, C.M., Busk, H., Malmqvist, L., Elfman, M., Malmqvist, K.G., Pallon, J., Sjoland, K.A., Utui, R.J., Yang, C., Kristiansson, P., Nilsson, C.M., Busk, H., Malmqvist, L., Elfman, M., Malmqvist, K.G., Pallon, J., Sjoland, K.A., Utui, R.J., and Yang, C.

Abstract

A technique for measuring optical dot gain, i.e. the relative difference between the actual screen dot and the optically perceived one, is presented. By combining measurements from the non-optical nuclear microprobe with data from image analyzing technique the optical dot gain can be determined. The procedure to reach pixel by pixel correlation on a micrometer scale is discussed. In the newsprint sample studied in this investigation a typical optical dot gain between 15 and 20% was deduced. The variation in the optical dot gain was correlated with other characteristic parameters of the print and newsprint and especially a positive correlation to the mass density of the newsprint was observed. (C) 1997 Elsevier Science Ltd.

Published
1997
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45. New Insights into Fish Ecology via Nuclear Microscopy of Otoliths.

Author

Limburg, K.E., Elfman, M., Kristiansson, P., Malmkvist, K., and Pallon, J.

Subjects
*OTOLITHS, *FISHES, *MARINE ecology, *MICROCHEMISTRY
Abstract

Otoliths, or earstones, are small, biogenic concretions of aragonitic calcium carbonate precipitated on a protein matrix. Otoliths form part of the hearing and balance system in teleost fishes, and grow as the fish grow, providing a continuous biochronology of growth. Various elements are entrained in minor and trace quantities. In particular, strontium is a useful scalar of habitat use when variable environmental gradients exist. By mapping elemental concentrations and ratios with the Lund nuclear microprobe, we have used strontium in many cases as a proxy for salinity, because Sr:Ca values are roughly an order of magnitude higher in marine vs most fresh waters. In addition, zinc shows strong seasonal variations in salmoniform fishes (salmons, charrs, and whitefishes have been tested to date). We present case studies of several species, and discuss exciting future directions in this research that is revolutionizing fisheries ecology. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]

Published
2003
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