With the popularization of carbon and nitrogen stable-isotope analysis methods used on archaeological samples from Xinjiang, the ancient paleodiet there has been revealed. However, research about isotopic analysis combined with environmental factors is rare, especially in such a variable and complex climate as that of the Tianshan region. We systematically analyzed the δ13C and δ15N results from animals and humans for dietary reconstruction of nomadic pastoralists from the Tianshan region during 3900–1200 cal BP. The δ13C and δ15N values for animals (sheep/goat, horse and cattle; n = 57) have a wide range from –20.8‰ to –14.7‰ for δ13C (–19.2 ± 1.0‰) and 3.2‰ to 9.9‰ for δ15N (7.0 ± 1.2‰). The δ13C and δ15N values from humans range from –19.6 to –12.3‰ (–16.0 ± 1.5‰) and 7.1 to 16.7‰ (–13.6 ± 1.5‰), respectively. The animal δ15N results indicate that the dry environment in the Tianshan region may result in elevated δ15N values. Synthesizing animal and human isotope results suggests that the inhabitants engaged in mobile herding economies subsidized with crops and wild animal meat from the Tianshan Mountains. In conclusion, we found that the regional environment closely relates to crop types, and temporal climate change has an effect on human dietary structure. Therefore, climate condition cannot be ignored when studying human paleodiet.

The material evidence of human presence in the Chontales region of central Nicaragua spans from 1420 ± 30 BP, or cal AD 554–670 (±2σ) through to the present, as was recently established (Donner and Geurds 2018). This cultural chronology, divided into three main periods, contrasts with the one previously proposed by (Gorin 1990), who defined six different phases from 500 BC through AD 1600. Here, we report on 11 new radiocarbon (14C) assays, introducing an update to the cultural sequence, consisting of two considerable changes, while also providing further overall strengthening. First, the earliest traces of human groups are now placed at 1645 ± 25 BP, or cal AD 263–536 (±2σ); second, five different periods are established for the research area. A recalibration of Gorin’s dates identified their consistency with the results reported here, supporting the new cultural chronology of central Nicaragua. Additionally, this study achieved the complete temporal characterization of Aguas Buenas, the largest pre-colonial archaeological site in Nicaragua.

This paper raises methodological issues of radiocarbon (14C) dating of historical events based on data obtained during the excavations of the Russian medieval city of Yaroslavl. The city is of special interest to our study because of the precise time of its destruction by troops of Batu Khan mentioned in chronicles—the winter of 1238. To date in Yaroslavl, researchers have discovered 9 mass burials of citizens and domestic animals buried sometime after the massacre by the Mongols. Mass burials of people alongside animals in a common grave and outside of the cemetery, in violation of Christian traditions, are not typical of medieval Russia and are a sign of a military catastrophe. To test this hypothesis, we dated a total of 65 samples representing all 9 mass burials. A Bayesian chronological model of the accelerator mass spectrometry (AMS) dates narrowed the interval to the range of 1197–1280 cal AD, with the mean age of 1239 AD, consistent with the hypothesis that the studied mass burials of citizens and livestock are related to the capture of the city by the army of Batu Khan.

The Jiaojia site is the earliest city in the Haidai area of China, about 5000 years old. To obtain more accurately the beginning and end of this site, radiocarbon accelerator mass spectrometry (14C AMS) measurements, along with stable carbon and nitrogen isotope data, were collected from 13 bone samples. According to the measured dates, human diet was dominated by C4-based plants, and the Jiaojia site appeared before 2900 BC.

Until recently, there was a lack of radiocarbon (14C) dates from the Bronze and Earliest Iron Age (1800–500–1 BC) burial sites in Latvia. The chronology of the sites was assessed on the basis of archaeological analogies with neighboring regions and typological studies of the rather meagre grave inventory. In order to establish a firm foundation for an absolute chronology of burial sites and to better understand changes in mortuary practices during the period, sequences of samples from various burial sites have been dated. In this paper we report 48 14C dates from 12 different sites and discuss them in the context of previously established archaeological chronologies. 14C reservoir effects are addressed: regarding FRE, stable isotope analysis is helpful; however, more data should be gathered in future research. In some cases, the new dates are in accord with previous chronologies, while in other cases some widely accepted assumptions may need to be revised. The new dates have proved false several previous assumptions about both the dates of individual graves and whole sites. Based on the 14C dates, we model the chronological spread of burial barrows in Latvia along waterways, the earliest examples appearing in coastal western Latvia.

A new facility for radiocarbon dating by accelerator mass spectrometry (AMS) was established in early 2015 at the Inter-University Accelerator Centre in New Delhi, India. The facility uses a 500 kV National Electrostatic Corporation (NEC) Pelletron accelerator for AMS measurements on graphite produced using the automated graphitization equipment (AGE) interfaced with an elemental analyzer and the carbonate handling system (CHS). A precision of better than 1‰ in the ratio of 14C/12C for the modern carbon sample and the background level of 1 × 10–15 from dead carbon sample has been achieved. This is the first dedicated accelerator of India only for AMS activities. This AMS system has the capabilities to perform 10Be and 26Al measurements as well.

The Royal Institute for Cultural Heritage (RICH) radiocarbon (14C) laboratory in Brussels, Belgium, has acquired experience for pretreating samples with 60 years of involvement in 14C dating, and the implementation of routine protocols. These procedures as applied to wood, seeds, charred materials, bones, ivory, textiles (silk, wool, cotton, linen), paper, shells, cremated bones, mortars, lead carbonates, sediments, etc. are described in detail in this paper. They are evaluated against reference materials.