Intestinal Absorption of Trace Amounts of Aluminium in Rats Studied with 26Aluminium and Accelerator Mass Spectrometry

1997 ◽  
Vol 92 (4) ◽  
pp. 379-383 ◽  
Author(s):  
K. W. Schönholzer ◽  
R. A. L. Sutton ◽  
V. R. Walker ◽  
V. Sossi ◽  
M. Schulzer ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Intestinal Absorption ◽  
Accelerator Mass Spectrometry ◽  
Aluminium Hydroxide ◽  
Sodium Citrate ◽  
Peak Plasma ◽  
Strong Positive Correlation ◽  
Aluminium Absorption ◽  
Aluminium Citrate ◽  
Blood And Urine Samples

1. Until recently studies of intestinal aluminium absorption used pharmacological amounts of stable 27Al. 2. To examine the intestinal absorption of trace amounts of different chemical compounds of aluminium, in the present study we have employed the long half-life isotope of aluminium, 26Al, and accelerator mass spectrometry. Trace amounts of 26Al (2.7–12.1 ng) as the hydroxide, citrate, citrate plus 1 mmol/kg sodium citrate, or maltolate respectively, were administered to four groups of rats (n = 9 per group) by gavage. Blood and urine samples were collected for 5 h and the 26Al content (as a percentage of the administered dose) determined by accelerator mass spectrometry. 3. The 5 h urinary 26Al excretion amounted to 0.1 ± 0.02, 0.7 ± 0.2, 5.1 ± 1.5 and 0.1 ± 0.1% of administered dose in the four groups respectively. There was a strong positive correlation between peak plasma 26Al (r = 0.98) and urinary 26Al excretion in individual animals (P < 0.001). 4. We conclude that the fractional intestinal absorption of trace oral doses of aluminium hydroxide is at least 0.1% (compared with the previous estimate of 0.01% using large 27Al oral loads). Absorption of aluminium citrate given alone is significantly greater (0.7%) and is further increased to 5% by the accompanying sodium citrate, consistent with an enhancing effect of added citrate upon mucosal aluminium permeability. Aluminium maltolate absorption approximates that of aluminium hydroxide (0.1%).

scholarly journals Hiatus in Prehistoric Chronology of the Cis-Baikal Region, Siberia: Pattern or Artifact?

Radiocarbon ◽  
2007 ◽  
Vol 49 (1) ◽  
pp. 123-129 ◽  
Author(s):  
Yaroslav V Kuzmin
Keyword(s):  
Mass Spectrometry ◽  
Accelerator Mass Spectrometry ◽  
Baikal Region ◽  
Critical Evaluation ◽  
Burial Grounds

The problem of a hiatus at about 6100–5300 BP (about 4900–4200 cal BC) in the prehistoric chronology of the Cis-Baikal region in Siberia is discussed. Based on a critical evaluation of existing evidence, there was no discontinuity found in the cultural sequence between the Kitoi and Serovo/Glazkovo complexes of the Neolithic, and the proposed “hiatus” may be an artifact based on underestimation of solid data. Conventional 14C dates are presented that were generated in the 1980s to early 2000s for Cis-Baikal prehistoric burial grounds, and were later dated by the accelerator mass spectrometry (AMS).

scholarly journals 14C INTERCOMPARISON EXERCISE ON BONES AND IVORY SAMPLES: IMPLICATIONS FOR FORENSICS

Radiocarbon ◽  
2021 ◽  
pp. 1-12
Author(s):  
G Quarta ◽  
M Molnár ◽  
I Hajdas ◽  
L Calcagnile ◽  
I Major ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
International Atomic Energy Agency ◽  
Accelerator Mass Spectrometry ◽  
Reference Curve ◽  
Nuclear Testing ◽  
Energy Agency ◽  
Widespread Application ◽  
Intercomparison Exercise ◽  
High Degree ◽  
Data Calibration

ABSTRACT The application of accelerator mass spectrometry radiocarbon (AMS 14C) dating in forensics is made possible by the use of the large excursion of the 14C concentration in the post-WWII terrestrial atmosphere due to nuclear testing as a reference curve for data calibration. By this approach high-precision analyses are possible on samples younger than ∼70 years. Nevertheless, the routine, widespread application of the method in the practice of forensics still appears to be limited by different issues due to possible complex interpretation of the results. We present the results of an intercomparison exercise carried out in the framework of an International Atomic Energy Agency (IAEA) CRP-Coordinated Research Project between three AMS laboratories in Italy, Hungary, and Switzerland. Bone and ivory samples were selected with ages spanning from background (>50 ka) to 2018. The results obtained allow us to assess the high degree of reproducibility of the results and the remarkable consistency of the experimental determinations.

scholarly journals Dating of Cremated Bones

Radiocarbon ◽  
2001 ◽  
Vol 43 (2A) ◽  
pp. 249-254 ◽  
Author(s):  
J N Lanting ◽  
A T Aerts-Bijma ◽  
J van der Plicht
Keyword(s):  
Mass Spectrometry ◽  
Success Rate ◽  
Accelerator Mass Spectrometry ◽  
Bone Collagen ◽  
Organic Fraction ◽  
Mineral Fraction

When dating unburnt bone, bone collagen, the organic fraction of the bone, is used. Collagen does not survive the heat of the cremation pyre, so dating of cremated bone has been considered impossible. Structural carbonate in the mineral fraction of the bone, however, survives the cremation process. We developed a method of dating cremated bone by accelerator mass spectrometry (AMS), using this carbonate fraction. Here we present results for a variety of prehistoric sites and ages, showing a remarkable success rate for this method.

scholarly journals THE BEGINNING OF THE IRON AGE AT ARSLANTEPE: A 14C PERSPECTIVE

Radiocarbon ◽  
2021 ◽  
pp. 1-19
Author(s):  
Federico Manuelli ◽  
Cristiano Vignola ◽  
Fabio Marzaioli ◽  
Isabella Passariello ◽  
Filippo Terrasi
Keyword(s):  
Mass Spectrometry ◽  
Bronze Age ◽  
High Precision ◽  
Iron Age ◽  
Accelerator Mass Spectrometry ◽  
Late Bronze Age ◽  
13Th Century ◽  
Historical Events ◽  
Preliminary Results ◽  
Archaeological Data

ABSTRACT The Iron Age chronology at Arslantepe is the result of the interpretation of Luwian hieroglyphic inscriptions and archaeological data coming from the site and its surrounding region. A new round of investigations of the Iron Age levels has been conducted at the site over the last 10 years. Preliminary results allowed the combination of the archaeological sequence with the historical events that extended from the collapse of the Late Bronze Age empires to the formation and development of the new Iron Age kingdoms. The integration into this picture of a new set of radiocarbon (14C) dates is aimed at establishing a more solid local chronology. High precision 14C dating by accelerator mass spectrometry (AMS) and its correlation with archaeobotanical analysis and stratigraphic data are presented here with the purpose of improving our knowledge of the site’s history and to build a reliable absolute chronology of the Iron Age. The results show that the earliest level of the sequence dates to ca. the mid-13th century BC, implying that the site started developing a new set of relationships with the Levant already before the breakdown of the Hittite empire, entailing important historical implications for the Syro-Anatolian region at the end of the 2nd millennium BC.

RADIOCARBON IN MEXICO: FROM PROPORTIONAL COUNTERS TO AMS

Radiocarbon ◽  
2021 ◽  
pp. 1-7
Author(s):  
Corina Solís ◽  
Efraín Chávez ◽  
Arcadio Huerta ◽  
María Esther Ortiz ◽  
Alberto Alcántara ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Sample Preparation ◽  
High Voltage ◽  
Accelerator Mass Spectrometry ◽  
Science And Technology ◽  
National Council ◽  
University Of Arizona ◽  
Technological Developments ◽  
High Voltage Engineering ◽  
The University

ABSTRACT Augusto Moreno is credited with establishing the first radiocarbon (14C) laboratory in Mexico in the 1950s, however, 14C measurement with the accelerator mass spectrometry (AMS) technique was not achieved in our country until 2003. Douglas Donahue from the University of Arizona, a pioneer in using AMS for 14C dating, participated in that experiment; then, the idea of establishing a 14C AMS laboratory evolved into a feasible project. This was finally reached in 2013, thanks to the technological developments in AMS and sample preparation with automated equipment, and the backing and support of the National Autonomous University of Mexico and the National Council for Science and Technology. The Mexican AMS Laboratory, LEMA, with a compact 1 MV system from High Voltage Engineering Europa, and its sample preparation laboratories with IonPlus automated graphitization equipment, is now a reality.

scholarly journals Quality Dating: A Well-Defined Protocol Implemented at ETH for High-Precision 14C-Dates Tested on Late Glacial Wood

Radiocarbon ◽  
2019 ◽  
Vol 62 (4) ◽  
pp. 891-899 ◽  
Author(s):  
Adam Sookdeo ◽  
Bernd Kromer ◽  
Ulf Büntgen ◽  
Michael Friedrich ◽  
Ronny Friedrich ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Tree Ring ◽  
High Precision ◽  
Accelerator Mass Spectrometry ◽  
Late Glacial ◽  
Tree Ring Chronology ◽  
Continuous Measurements ◽  
Calibration Curves

ABSTRACTAdvances in accelerator mass spectrometry have resulted in an unprecedented amount of new high-precision radiocarbon (14C) -dates, some of which will redefine the international 14C calibration curves (IntCal and SHCal). Often these datasets are unaccompanied by detailed quality insurances in place at the laboratory, questioning whether the 14C structure is real, a result of a laboratory variation or measurement-scatter. A handful of intercomparison studies attempt to elucidate laboratory offsets but may fail to identify measurement-scatter and are often financially constrained. Here we introduce a protocol, called Quality Dating, implemented at ETH-Zürich to ensure reproducible and accurate high-precision 14C-dates. The protocol highlights the importance of the continuous measurements and evaluation of blanks, standards, references and replicates. This protocol is tested on an absolutely dated German Late Glacial tree-ring chronology, part of which is intercompared with the Curt Engelhorn-Center for Archaeometry, Mannheim, Germany (CEZA). The combined dataset contains 170 highly resolved, highly precise 14C-dates that supplement three decadal dates spanning 280 cal. years in IntCal, and provides detailed 14C structure for this interval.

Sign in / Sign up

Export Citation Format

Share Document