scholarly journals Dating and Digging Stratified Archaeology in Circumpolar North America: A View from Nunalleq, Southwestern Alaska

ARCTIC ◽  
2016 ◽  
Vol 69 (4) ◽  
pp. 378 ◽  
Author(s):  
Paul M. Ledger ◽  
Véronique Forbes ◽  
Edouard Masson-MacLean ◽  
Richard A. Knecht
Keyword(s):  
North America ◽  
Rangifer Tarandus ◽  
Sample Selection ◽  
Bone Collagen ◽  
Archaeological Sites ◽  
14C Dating ◽  
The North ◽  
Rubus Chamaemorus ◽  
14C Age ◽  
Circumpolar North

Through the case study of the Thule-era village site of Nunalleq (GDN-248), this paper presents 14C dating results and perspectives on the issues associated with radiocarbon dating stratified archaeological sites in circumpolar North America. The objective was to investigate relative variation in the 14C age of ecofacts with the aim of establishing a hierarchy of dating suitability for Nunalleq that could more widely inform 14C sample selection on archaeological sites across the North American sub-Arctic and Arctic and Greenland. Owing to the complexities associated with interpreting and establishing the relative chronology of the deeply stratified sod deposits at Nunalleq, we adopted open-area excavation and single-context recording methods. This approach, we suggest, allowed us to eliminate stratigraphic complexity as a source of variation in 14C measurements and to assess the taphonomic issues associated with dating different ecofacts. In total, 16 samples were submitted for dating, comprising two sets of eight different ecofacts, one from each of two stratigraphically contemporary but spatially discrete contexts. In most instances, the 14C ages of ecofacts were statistically indistinguishable between the two contexts and support the relative chronological relationships established by excavation. Only Elymus arenarius (grass) manufactures and Heleomyzidae (fly) puparia produced different ages in the two contexts, variations that suggest that these items are unreliable dating materials. As noted in previous studies, Phoca sp. (seal) and Oncorhynchus sp. (salmon) bone collagen demonstrated a strong marine reservoir effect (c. 700 14C yr.). Picea sp. (wood chips) were marginally older than seeds from edible berries (Rubus chamaemorus and Empetrum nigrum) and caribou (Rangifer tarandus) bone collagen, which provided the most consistent ages.

scholarly journals Reservoirs and Radiocarbon: 14C Dating Problems in Mývatnssveit, Northern Iceland

Radiocarbon ◽  
2007 ◽  
Vol 49 (2) ◽  
pp. 947-961 ◽  
Author(s):  
Philippa L Ascough ◽  
Gordon T Cook ◽  
Mike J Church ◽  
Andrew J Dugmore ◽  
Thomas H McGovern ◽  
...  
Keyword(s):  
Isotope Composition ◽  
Bone Collagen ◽  
Archaeological Sites ◽  
North Coast ◽  
Spatial Gradient ◽  
Reservoir Effect ◽  
Terrestrial Mammal ◽  
Terrestrial Mammals ◽  
The North ◽  
Geothermal Activity

This paper examines 2 potential sources of the radiocarbon offset between human and terrestrial mammal (horse) bones recovered from Norse (∼AD 870–1000) pagan graves in Mývatnssveit, north Iceland. These are the marine and freshwater 14C reservoir effects that may be incorporated into human bones from dietary sources. The size of the marine 14C reservoir effect (MRE) during the Norse period was investigated by measurement of multiple paired samples (terrestrial mammal and marine mollusk shell) at 2 archaeological sites in Mývatnssveit and 1 site on the north Icelandic coast. These produced 3 new δR values for the north coast of Iceland, indicating a δR of 106 ± 10 14C yr at AD 868–985, and of 144 ± 28 14C yr at AD 1280–1400. These values are statistically comparable and give an overall weighted mean δR of 111 ± 10 14C yr.The freshwater reservoir effect was similarly quantified using freshwater fish bones from a site in Mývatnssveit. These show an offset of between 1285 and 1830 14C yr, where the fish are depleted in 14C relative to the terrestrial mammals. This is attributed to the input of geothermally derived CO2 into the groundwater and subsequently into Lake Mývatn. We conclude the following: i) some of the Norse inhabitants of Mývatnssveit incorporated non-terrestrial resources into their diet that may be identified from the stable isotope composition of their bone collagen; ii) the MRE off the north Icelandic coast during the Norse period fits a spatial gradient of wider North Atlantic MRE values with increasing values to the northwest; and iii) it is important to consider the effect that geothermal activity could have on the 14C activity of samples influenced by groundwater at Icelandic archaeological sites.

scholarly journals AMS 14C Dating at the Scottish Universities Environmental Research Centre (SUERC) Radiocarbon Dating Laboratory

Radiocarbon ◽  
2016 ◽  
Vol 58 (1) ◽  
pp. 9-23 ◽  
Author(s):  
E Dunbar ◽  
G T Cook ◽  
P Naysmith ◽  
B G Tripney ◽  
S Xu
Keyword(s):  
Radiocarbon Dating ◽  
Tooth Enamel ◽  
Sample Selection ◽  
Sample Pretreatment ◽  
Bone Collagen ◽  
Environmental Research ◽  
Research Centre ◽  
14C Dating ◽  
Commercial Activities ◽  
Main Emphasis

AbstractThis paper describes all the major procedures adopted by the Scottish Universities Environmental Research Centre (SUERC) Radiocarbon Dating Laboratory. This includes sample pretreatment, graphite production, accelerator mass spectrometry (AMS) measurement, associated stable isotope measurements, data handling, and age calculations, but with the main emphasis being on the chemical pretreatment methods. All of the above enable the laboratory to provide a complete analytical service comprising advice on sample selection, preparation and analysis of samples, and Bayesian analysis of resulting 14C (and other) data. This applies to both our research and commercial activities. The pretreatment methods that we mainly focus on are used to remove contaminant carbon from a range of sample types or to isolate a particular chemical fraction from a sample prior to combustion/hydrolysis, graphitization, and subsequent AMS 14C measurement. The methods described are for bone (collagen extraction, with and without ultrafiltration), cremated bone, tooth enamel, charcoal, grain, carbon residues, shell, wood (including alpha-cellulose isolation), peat, sediments, textiles, fuel/biofuel, and forensic samples.

Political orientation and moral foundations

2019 ◽  
Vol 118 (11) ◽  
pp. 365-371
Author(s):  
J Dorasamy ◽  
Mr Jirushlan Dorasamy
Keyword(s):  
South Africa ◽  
North America ◽  
American Studies ◽  
Political Orientation ◽  
The Political ◽  
Moral Foundations ◽  
Open Approach ◽  
Online Questionnaire ◽  
Moral Foundation ◽  
The North

Studies, especially in the North America, have shown a relationship between political orientation and moralfoundation. This study investigated whether moral judgements differ from the political orientation of participantsin South Africa moral judgment and the extent to which moral foundations are influenced by politicalorientation.Further, the study investigated the possibility of similar patterns with the North AmericanConservative-Liberal spectrum and the moral foundation. There were 300participants, 78 males and 222 females,who completed an online questionnaire relating to moral foundation and political orientation. The results partiallysupported the hypothesis relating to Liberal and Conservative orientation in South Africa. Further, this studypartially predicted the Liberal-Conservative orientation with patterns in the moral foundation, whilst showingsimilar findings to the North American studies. A growing rate of a neutral/moderate society is evidenced in SouthAfrica and abroad, thereby showing the emergence of a more open approach to both a political and generalstance.”””

РАДИОУГЛЕРОДНЫЕ ДАТИРОВКИ ПАЛЕОНТОЛОГИЧЕСКИХ ОБРАЗЦОВ ВЕРХНЕГО ПЛЕЙСТОЦЕНА НИЖНЕЙ ОБИ

2020 ◽  
Author(s):  
I. Zolnikov ◽  
◽  
A. Vybornov ◽  
A. Anoikin ◽  
A. Postnov ◽  
...  
Keyword(s):  
Mass Spectrometer ◽  
Rangifer Tarandus ◽  
Western Siberia ◽  
Budker Institute ◽  
Mammuthus Primigenius ◽  
Upper Pleistocene ◽  
Ovibos Moschatus ◽  
The North

In the course of studies conducted by IAET SB RAS in the Lower Ob in 2016–2019, the understanding of the conditions for settlement of the Paleolithic population in the north of Western Siberia was significantly supplemented. Dating of a series of paleontological finds was carried out at the "Accelerated mass spectrometer of the Budker Institute of Nucle- ar Physics of SB RAS". The dates obtained show the distribution of the main representatives of the Upper Pleistocene fauna of Subarctica: Mammuthus primigenius – 50,000–15,000 BP, Coelodonta antiquitatis – 43,000–38,000 BP and 27,000–25,000 BP, Rangifer tarandus, Equus ferus – 40,000–10,000 BP, Bison sp. – 50,000–40,000 BP, Ovibos moschatus – 41,000–32,000 BP.

scholarly journals Progress in Diagnosing Primary Ciliary Dyskinesia: The North American Perspective

Diagnostics ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1278
Author(s):  
Michael Glenn O’Connor ◽  
Amjad Horani ◽  
Adam J. Shapiro
Keyword(s):  
Genetic Testing ◽  
North America ◽  
North American ◽  
Primary Ciliary Dyskinesia ◽  
Clinical Phenotype ◽  
The United States ◽  
Diagnostic Process ◽  
The North ◽  
Diagnostic Guideline ◽  
Ciliary Dyskinesia

Primary Ciliary Dyskinesia (PCD) is a rare, under-recognized disease that affects respiratory ciliary function, resulting in chronic oto-sino-pulmonary disease. The PCD clinical phenotype overlaps with other common respiratory conditions and no single diagnostic test detects all forms of PCD. In 2018, PCD experts collaborated with the American Thoracic Society (ATS) to create a clinical diagnostic guideline for patients across North America, specifically considering the local resources and limitations for PCD diagnosis in the United States and Canada. Nasal nitric oxide (nNO) testing is recommended for first-line testing in patients ≥5 years old with a compatible clinical phenotype; however, all low nNO values require confirmation with genetic testing or ciliary electron micrograph (EM) analysis. Furthermore, these guidelines recognize that not all North American patients have access to nNO testing and isolated genetic testing is appropriate in cases with strong clinical PCD phenotypes. For unresolved diagnostic cases, referral to a PCD Foundation accredited center is recommended. The purpose of this narrative review is to provide insight on the North American PCD diagnostic process, to enhance the understanding of and adherence to current guidelines, and to promote collaboration with diagnostic pathways used outside of North America.

scholarly journals Future Changes in Tropical Cyclone and Easterly Wave Characteristics over Tropical North America

Oceans ◽  
2021 ◽  
Vol 2 (2) ◽  
pp. 429-447
Author(s):  
Christian Dominguez ◽  
James M. Done ◽  
Cindy L. Bruyère
Keyword(s):  
North America ◽  
North Atlantic Ocean ◽  
Mitigation Strategies ◽  
Track Density ◽  
Caribbean Region ◽  
Tropical Cyclogenesis ◽  
Future Scenarios ◽  
Southern Mexico ◽  
The North ◽  
The Future

Tropical Cyclones (TCs) and Easterly Waves (EWs) are the most important phenomena in Tropical North America. Thus, examining their future changes is crucial for adaptation and mitigation strategies. The Community Earth System Model drove a three-member regional model multi-physics ensemble under the Representative Concentration Pathways 8.5 emission scenario for creating four future scenarios (2020–2030, 2030–2040, 2050–2060, 2080–2090). These future climate runs were analyzed to determine changes in EW and TC features: rainfall, track density, contribution to seasonal rainfall, and tropical cyclogenesis. Our study reveals that a mean increase of at least 40% in the mean annual TC precipitation is projected over northern Mexico and southwestern USA. Slight positive changes in EW track density are projected southwards 10° N over the North Atlantic Ocean for the 2050–2060 and 2080–2090 periods. Over the Eastern Pacific Ocean, a mean increment in the EW activity is projected westwards across the future decades. Furthermore, a mean reduction by up to 60% of EW rainfall, mainly over the Caribbean region, Gulf of Mexico, and central-southern Mexico, is projected for the future decades. Tropical cyclogenesis over both basins slightly changes in future scenarios (not significant). We concluded that these variations could have significant impacts on regional precipitation.

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