scholarly journals Neodymium isotopes in modern human dental enamel: an exploratory dataset for human provenancing

Data in Brief ◽  
2021 ◽  
pp. 107375
Author(s):  
Esther Plomp
2020 ◽  
Vol 172 (4) ◽  
pp. 586-604 ◽  
Author(s):  
Esther Plomp ◽  
Isabella C. C. Holstein ◽  
Lisette M. Kootker ◽  
Suzanne J. A. Verdegaal‐Warmerdam ◽  
Tim Forouzanfar ◽  
...  

2014 ◽  
Vol 10 (10) ◽  
pp. 20140484 ◽  
Author(s):  
Charles Ziscovici ◽  
Peter W. Lucas ◽  
Paul J. Constantino ◽  
Timothy G. Bromage ◽  
Adam van Casteren

Dental enamel is prone to damage by chipping with large hard objects at forces that depend on chip size and enamel toughness. Experiments on modern human teeth have suggested that some ante-mortem chips on fossil hominin enamel were produced by bite forces near physiological maxima. Here, we show that equivalent chips in sea otter enamel require even higher forces than human enamel. Increased fracture resistance correlates with more intense enamel prism decussation, often seen also in some fossil hominins. It is possible therefore that enamel chips in such hominins may have formed at even greater forces than currently envisaged.


2020 ◽  
Vol 729 ◽  
pp. 138992 ◽  
Author(s):  
Lisette M. Kootker ◽  
Esther Plomp ◽  
Saskia T.M. Ammer ◽  
Vera Hoogland ◽  
Gareth R. Davies

Author(s):  
L. D. Ackerman ◽  
S. H. Y. Wei

Mature human dental enamel has presented investigators with several difficulties in ultramicrotomy of specimens for electron microscopy due to its high degree of mineralization. This study explores the possibility of combining ion-milling and high voltage electron microscopy as a means of circumventing the problems of ultramicrotomy.A longitudinal section of an extracted human third molar was ground to a thickness of about 30 um and polarized light micrographs were taken. The specimen was attached to a single hole grid and thinned by argon-ion bombardment at 15° incidence while rotating at 15 rpm. The beam current in each of two guns was 50 μA with an accelerating voltage of 4 kV. A 20 nm carbon coating was evaporated onto the specimen to prevent an electron charge from building up during electron microscopy.


Author(s):  
M. John Hicks

Acid-etching of enamel surfaces has been performed routinely to bond adhesive resin materials to sound dental enamel as a caries-preventive measure. The effect of fluoride pretreatment on acid-etching of enamel has been reported to produce inconsistent and unsatisfactory etching patterns. The failure to obtain an adequate etch has been postulated to be due to fluoride precipitation products deposited on the enamel surface. The purpose of this study was to evaluate the effects of fluoride pretreatment on acid-etching of carieslike lesions of human dental enamel.Caries-like lesions of enamel were created in vitro on human molar and premolar teeth. The teeth were divided into two fluoride treatment groups. The specimens were exposed for 4 minutes to either a 2% Sodium Fluoride (NaF) solution or a 10% Stannous Fluoride (SnF2) solution. The specimens were then washed in deionized-distilled water. Each tooth was sectioned into four test regions. This was carried out to compare the effects of various time exposures (0 to 2 minutes) and differing concentrations (10 to 60% w/w) of phosphoric acid (H3PO4) on etching of caries-like lesions. Standard preparation techniques for SEM were performed on the specimens.


Author(s):  
T. L. Hayes

Biomedical applications of the scanning electron microscope (SEM) have increased in number quite rapidly over the last several years. Studies have been made of cells, whole mount tissue, sectioned tissue, particles, human chromosomes, microorganisms, dental enamel and skeletal material. Many of the advantages of using this instrument for such investigations come from its ability to produce images that are high in information content. Information about the chemical make-up of the specimen, its electrical properties and its three dimensional architecture all may be represented in such images. Since the biological system is distinctive in its chemistry and often spatially scaled to the resolving power of the SEM, these images are particularly useful in biomedical research.In any form of microscopy there are two parameters that together determine the usefulness of the image. One parameter is the size of the volume being studied or resolving power of the instrument and the other is the amount of information about this volume that is displayed in the image. Both parameters are important in describing the performance of a microscope. The light microscope image, for example, is rich in information content (chemical, spatial, living specimen, etc.) but is very limited in resolving power.


2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Mashkoor Ahmad Lone ◽  
Dr. P. Ganesan

The practice of placing deprived children having least or no emotional and material resources, in orphanages has since long been prevailing in socio -economically poor Asian countries. A sample of 30 children residing in orphanage in district Anantnag in the age group of 13-18 years was selected for the present study. Most of the children were found socially and psychologically disturbed. As per Indian Academy Paediatrics (IAP) classification with respect to weight for age the condition was not bad that as approximately 67% percent of the children were found to be normal. In the same way height for age as per Waterloo’s classification shown that more than half of the children were normal. On clinical examination approximately 47% of children were normal, while as rest were suffering from dispigmentation of hair, moon face, xerosis of skin cheilosis, magenta tongue, spongy bleeding gums, oedema, conjuctival xerosis, and mottled dental enamel. The findings indicated that nutritional intake was deficient for all nutrients when compared to, Recommended Daily Allowances Chart (RDA) for all age groups which may be linked to poor planning of menus in orphanages.


2011 ◽  
Vol 2 (2) ◽  
pp. 69-112
Author(s):  
Pierre Legendre

"Der Beitrag reevaluiert die «dogmatische Funktion», eine soziale Funktion, die mit biologischer und kultureller Reproduktion und folglich der Reproduktion des industriellen Systems zusammenhängt. Indem sie sich auf der Grenze zwischen Anthropologie und Rechtsgeschichte des Westens situiert, nimmt die Studie die psychoanalytische Frage nach der Rolle des Rechts im Verhalten des modernen Menschen erneut in den Blick. </br></br>This article reappraises the dogmatic function, a social function related to biological and cultural reproduction and consequently to the reproduction of the industrial system itself. On the borderline of anthropology and of the history of law – applied to the West – this study takes a new look at the question raised by psychoanalysis concerning the role of law in modern human behaviour. "


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