Linking Identity with Landscape: Osteological and Sr–Pb Isotopic Methods for Biogeoreference

2014 ◽  
pp. 260-277
Keyword(s):  
Isotopic Methods

scholarly journals Ore-Bearing Magmatic Systems with Complex Sn–Au–Ag Mineralization in the North-Eastern Verkhoyansk–Kolyma Orogenic Belt, Russia

Minerals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 266
Author(s):  
Vera A. Trunilina ◽  
Andrei V. Prokopiev
Keyword(s):  
Active Continental Margin ◽  
Orogenic Belt ◽  
Crustal Extension ◽  
Margin Setting ◽  
The North ◽  
Magmatic Rocks ◽  
Isotopic Methods ◽  
North Eastern ◽  
Magmatic Stage ◽  
Mineral Compositions

This paper reports the results of a study of magmatic rocks with Sn–W–Au–Ag mineralization from the Kuranakh, Elikchan, and Istekh ore fields in the Northern batholith belt of the north-eastern Verkhoyansk–Kolyma orogenic belt in Eastern Russia. Using petrographic, mineralogical, geochemical, and isotopic methods, we determined the mineral compositions, petrochemistry, and geochemistry of magmatic rocks, the P–T conditions of their generation and crystallization, and their geodynamic affinity. The studied magmatic rocks have common geochemical characteristics that likely reflect the influence of fluids supplied from a long-lived, deep-seated mantle source. The ore fields are characterized by Sn–W–Au–Ag–Pb polygenetic mineralization. The magmatic and metallogenic evolution comprised five stages for the formation of magmatic rocks and ores. During the first stage (Berriasian–Barremian), arc-related magmatic rocks formed in an active continental margin setting and were associated with Au–Ag mineralization. The second, third, and fourth stages (Aptian–Campanian) took place in a crustal extension and rift setting, and were accompanied by Au–Ag and Sn–W mineralization. During the fifth (post-magmatic) stage, Sn–Ag–Sb and Pb–Ag mineralization occurred.

A comparison of three different isotopic methods for measuring body components of sheep

1978 ◽  
Vol 29 (12) ◽  
pp. 1007-1016 ◽  
Author(s):  
Timothy E. Trigg ◽  
Ernesto A. Domingo ◽  
John H. Topps
Keyword(s):  
Isotopic Methods ◽  
Body Components

scholarly journals STUDIES ON CYCLOPHOSPHAMIDE-INDUCED TOLERANCE TO SHEEP ERYTHROCYTES

1967 ◽  
Vol 125 (5) ◽  
pp. 833-845 ◽  
Author(s):  
Alan C. Aisenberg
Keyword(s):  
Tolerance Induction ◽  
Acid Synthesis ◽  
Progressive Increase ◽  
Immunological Tolerance ◽  
Receptor Sites ◽  
Deoxyribonucleic Acid Synthesis ◽  
Isotopic Methods ◽  
Radiation Induced ◽  
Immunological Suppression ◽  
Induced Tolerance

Complete immunological tolerance to sheep cells can be induced in mice when cyclophosphamide is injected together with sheep cells or up to 72 hr before or 48 hr after the antigen. As is true for radiation-induced immune suppression, the drug is most effective when given in the 24 hr prior to antigen. Complete cyclophosphamide-induced immunological suppression requires large doses of sheep cells (6.2 x 109 cells), presumably to enable antigen to reach sequestered receptor sites. The cyclophosphamide tolerance system has been analyzed with the Jerne technique to determine plaque-forming cells and with isotopic methods to measure rates of nucleic acid synthesis. This drug suppression has been found to consist of two components. The first is nonspecific injury to the lymphoid system caused by the cytotoxic drug and is related to the proportion of spleen cells killed. The second is antigen-specific immunological tolerance and appears to correlate with profound depression of deoxyribonucleic acid synthesis in the surviving cells. This tolerance is thought to be most consistent with a mechanism in which antigenic stimulation in the presence of cyclophosphamide-inhibited DNA synthesis and mitosis leads to the elimination or death of the specific immunological clone. Tolerance induction with cyclophosphamide is associated with loss of the 19S hemolysin plaques which are seen in nonstimulated mouse spleen, implicating these cells in immune responsiveness. The ability to induce tolerance is lost on the 3rd postantigen day at the end of a 24-hr period in which 19S cells have increased 8-fold and 7S cells 200-fold. The data suggest that loss of sensitivity is due to the emergence on day 3 of drug-resistant plaque-forming cells, particularly those of the 19S variety. In the succeeding days after antigen injection there is a progressive increase in the resistance of plaque-forming cells to cyclophosphamide administration.

Bovine trypanosomiasis: the red cell kinetics of Ndama and Zebu cattle infected withTrypanosoma congolense

Parasitology ◽  
1979 ◽  
Vol 78 (3) ◽  
pp. 271-286 ◽  
Author(s):  
J. D. Dargie ◽  
P. K. Murray ◽  
Max Murray ◽  
W. R. T. Grimshaw ◽  
W. I. M. McIntyre
Keyword(s):  
Zebu Cattle ◽  
Red Cell ◽  
Isotopic Methods ◽  
Initial Drop ◽  
Bone Marrow Function ◽  
Cell Synthesis ◽  
Underlying Processes ◽  
Kinetics Of ◽  
Cell Volumes ◽  
Erythropoietic Response

SUMMARYThe responses of susceptible Ndama and Zebu cattle to needle challenge withTrypanosoma congolensewere followed using parasitological, haematological and radio-isotopic methods and compared with those of corresponding uninfected animals. In both breeds, infection became patent at the same time but peak parasitaemias were significantly lower, were attained later and were of short duration in the Ndama. All infected animals became anaemic, the severity of which correlated with the level and duration of parasitaemia. However, even when parasites could no longer be detected in the blood, packed cell volumes showed little tendency to recover. The anaemia was due to increased intravascular red cell destruction and was more pronounced in the Zebu. Haemodilution was not a feature. Increased red cell synthesis occurred in infected animals of both breeds but particularly in the Zebu; this accounted for the capacity to maintain packed cell volume levels following the initial drop associated with parasitaemia. However, in most cases red cell synthesis was less than expected from the degree of anaemia, suggesting impairment of bone marrow function. Measurement of red cell iron utilization indicated that this was due to defective iron re-utilization from degraded red cells arising from reticulo-endothelial blockade. It is concluded that the anaemia in this disease and its underlying processes are broadly in line with the number of parasites in the blood and that the superior resistance of the Ndama cattle lies in their ability to control parasitaemia rather than their capacity to mount a more efficient erythropoietic response.

scholarly journals Present-Day Radiocarbon Content of Select Flavoring Compounds Reveals Vanillin Production Pathway

Radiocarbon ◽  
2013 ◽  
Vol 55 (3) ◽  
pp. 1819-1826 ◽  
Author(s):  
Randy Culp ◽  
G V Ravi Prasad
Keyword(s):  
Stable Isotope ◽  
Fossil Fuel ◽  
Agricultural Products ◽  
Clove Oil ◽  
Isotopic Data ◽  
Established Method ◽  
New Methods ◽  
Isotopic Methods ◽  
Isotope Studies ◽  
The University

Radiocarbon and stable isotope determination in foods, flavors, and beverages, for the authentication of source material and process of formation, is a well-established method of identity used in industry. New methods of provenance determination, using stable isotopes of oxygen and hydrogen, have added to the host of other isotopic methods used for characterizing natural or botanically derived products. The unambiguous determinant of a product's fossil fuel origin be it from petroleum, natural gas, or coal, is through the measurement of its 14C content. The 14C content can also be used to determine the fraction dilution of recently grown and harvested material with that derived from fossil fuel, and even confirms the vintage of agricultural products based on the well-established decrease of bomb-produced atmospheric 14C. This paper documents 14C measurements at the University of Georgia's Center for Applied Isotope Studies accelerator mass spectrometry and stable isotope laboratories, over the last 3 yr, for 10 important flavoring compounds. By establishing an accurate and current level of 14C in botanically derived products, we were able to confirm a particular source for vanilla production, the most popular consumer flavor in the marketplace. Over the years, vanilla extract has been produced less and less from vanilla beans (Vanilla planifolia), particularly those from Madagascar and the Comoros Islands, and more from other botanical precursors such as ferulic acid, clove oil, and guaiacol. We report isotopic data to support this precursor for vanilla production based on high 14C levels accumulated during the tree's life, incorporated in the tree rings and their associated stable isotope abundances.

Rate of carbon dioxide production and energy expenditure in fed and food-deprived adult dogs determined by indirect calorimetry and isotopic methods

2002 ◽  
Vol 63 (1) ◽  
pp. 111-118 ◽  
Author(s):  
Etienne B. Pouteau ◽  
Sandrine M. Mariot ◽  
Lucile J. Martin ◽  
Henri J. Dumon ◽  
Francoise J. Mabon ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
Energy Expenditure ◽  
Indirect Calorimetry ◽  
Carbon Dioxide Production ◽  
Isotopic Methods
Sign in / Sign up

Export Citation Format

Share Document