Seasonality Determination by Oxygen Isotopic Profile: A Reply to Bailey et al.

1983 ◽  
Vol 48 (2) ◽  
pp. 399-403 ◽  
Author(s):  
John S. Killingley
Keyword(s):  
Oxygen Isotopic ◽  
O 18 ◽  
Tegula Funebralis ◽  
Isotopic Profile

A response is presented to the comment by Bailey et al. on the determination of seasonality of mollusk collecting using O-18 profiles of midden shells. Profiles were measured on two species of intertidal mollusks (Tegula funebralis and Collisella limatula) to provide further evidence for the applicability of the technique to seasonality studies.

An oxygen isotopic profile through the upper kilometer of the oceanic crust, DSDP Hole 504B

1986 ◽  
Vol 80 (3-4) ◽  
pp. 217-229 ◽  
Author(s):  
Jeffrey C. Alt ◽  
Karlis Muehlenbachs ◽  
Jose Honnorez
Keyword(s):  
Oceanic Crust ◽  
Oxygen Isotopic ◽  
Isotopic Profile

scholarly journals Oxygen isotopic fractionation in rat bones as a result of consuming thermally processed water – bioarchaeological applications

2020 ◽  
Vol 47 (1) ◽  
pp. 1-12 ◽  
Author(s):  
Aleksandra Lisowska-Gaczorek ◽  
Krzysztof Szostek ◽  
Jacek Pawlyta ◽  
Beata Cienkosz-Stepańczak
Keyword(s):  
Isotopic Composition ◽  
Environmental Variability ◽  
Isotope Analysis ◽  
Isotopic Fractionation ◽  
Migration Routes ◽  
Laboratory Rats ◽  
Regular Consumption ◽  
Thermally Processed ◽  
Oxygen Isotopic

AbstractStable isotope analyses of oxygen are used in anthropology for such purposes as determination of origin of individuals, tracking migration routes or dynamics of human community relocation. The methodology related to oxygen isotope analysis has been founded on the relationship between its isotopic composition within phosphate groups of bone tissue (δ18Op) in individuals being analysed and the water consumed by such individuals (δ18Ow). Such a relationship has been observed in many species of mammals, including humans. However, the influence of culinary practices on the isotopic delta values of apatite phosphates of individuals has not yet been researched. The present study, which was conducted using laboratory rats, is an investigation of the influence of the thermal processing of water drank by such rats on the isotopic composition (δ18Op) of bone apatite. Increasing the value of the isotopic composition of water by about 6.1 ‰ during boiling resulted in an increase in the oxygen isotopic value δ18Op of rats drinking the water by about 4 ‰ (29%). It can be expected that regular consumption of heavily isotopic drinks and foods by humans may cause the δ18Op of individuals to exceed the range of isotopic environmental variability, even by a few per mille.

scholarly journals Novel Microcystins from Planktothrix prolifica NIVA-CYA 544 Identified by LC-MS/MS, Functional Group Derivatization and 15N-labeling

Marine Drugs ◽  
2019 ◽  
Vol 17 (11) ◽  
pp. 643 ◽  
Author(s):  
Vittoria Mallia ◽  
Silvio Uhlig ◽  
Cheryl Rafuse ◽  
Juris Meija ◽  
Christopher O. Miles
Keyword(s):  
Functional Group ◽  
Profile Analysis ◽  
Sulfide Oxidation ◽  
Liquid Chromatography Mass Spectrometry ◽  
Cyanobacterium Anabaena ◽  
Product Ions ◽  
15N Labeling ◽  
Low Levels ◽  
Isotopic Profile

Microcystins are cyclic heptapeptides from cyanobacteria that are potent inhibitors of protein phosphatases and are toxic to animals and humans. At present, more than 250 microcystin variants are known, with variants reported for all seven peptide moieties. While d-glutamic acid (d-Glu) is highly-conserved at position-6 of microcystins, there has been only one report of a cyanobacterium (Anabaena) producing microcystins containing l-Glu at the variable 2- and 4-positions. Liquid chromatography–mass spectrometry analyses of extracts from Planktothrix prolifica NIVA-CYA 544 led to the tentative identification of two new Glu-containing microcystins, [d-Asp3]MC-ER (12) and [d-Asp3]MC-EE (13). Structure determination was aided by thiol derivatization of the Mdha7-moiety and esterification of the carboxylic acid groups, while 15N-labeling of the culture and isotopic profile analysis assisted the determination of the number of nitrogen atoms present and the elemental composition of molecular and product-ions. The major microcystin analog in the extracts was [d-Asp3]MC-RR (1). A microcystin with an unprecedented high-molecular-mass (2116 Da) was also detected and tentatively identified as a sulfide-linked conjugate of [d-Asp3]MC-RR (15) by LC–HRMS/MS and sulfide oxidation, together with its sulfoxide (16) produced via autoxidation. Low levels of [d-Asp3]MC-RW (14), [d-Asp3]MC-LR (4), [d-Asp3,Mser7]MC-RR (11), [d-Asp3]MC-RY (17), [d-Asp3]MC-RF (18), [d-Asp3]MC-RR–glutathione conjugate (19), and [d-Asp3]MC-RCit (20), the first reported microcystin containing citrulline, were also identified in the extract, and an oxidized derivative of [d-Asp3]MC-RR and the cysteine conjugate of 1 were partially characterized.

Modelling of chalk diagenesis (Eldfisk Field, Norwegian North Sea) using whole rock and laser ablation stable isotopic data

1991 ◽  
Vol 128 (1) ◽  
pp. 43-49 ◽  
Author(s):  
R. G. Maliva ◽  
J. A. D. Dickson ◽  
A. Råheim
Keyword(s):  
Laser Ablation ◽  
North Sea ◽  
Isotopic Ratios ◽  
Carbonate Mineral ◽  
Isotopic Data ◽  
Rock Interaction ◽  
Stable Isotopic ◽  
Oxygen Isotopic ◽  
First Time

AbstractLaser ablation techniques permit the determination of the stable isotopic ratios of finely crystalline calcite cements in chalks for the first time. Modelling of fluid–rock interaction using whole rock and laser ablation stable isotopic data indicates that carbonate mineral diagenesis in the Eldfisk Field consisted largely of the dissolution and reprecipitation of calcite with little associated loss of porosity. Cementation by calcite derived from stylolites apparently occurred throughout the Eldfisk Field chalk, but had only a subsidiary effect on whole rock isotopic ratios. Oxygen isotopic data indicates a pore water temperature of 50–80 °C during the bulk of chalk recrystallization. Increases in whole rock δ13C values with depth are likely the result of bacterial methanogenesis during chalk recrystallization.

Determination of the Dipole Moment of O-18 Methanol by Microwave Stark Spectroscopy

1996 ◽  
Vol 176 (1) ◽  
pp. 38-44 ◽  
Author(s):  
K.V.L.N. Sastry ◽  
I. Mukhopadhyay ◽  
P.K. Gupta ◽  
J. VanderLinde
Keyword(s):  
Dipole Moment ◽  
Stark Spectroscopy ◽  
O 18
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