Induced hydration of obsidian: a simulation study of accuracy requirements

Determination of the hydration rate constant of obsidian is basic to the use of obsidian for establishing chronologies. The constant can, in principle, be determined in either of two ways: by correlations with archaeological sequences, or by laboratory experiments using induced hydration. Induced hydration holds promise of great accuracy, but results reported to date have been disappointing. This paper is based on the hypothesis that the outcomes are the result of error build-up in the induced hydration protocol, and describes an analysis based on a Monte Carlo simulation of the measurement and analysis process. Data are presented which show that the poor results are due to errors inherent in optical measurement of hydration rim thickness. It is concluded that successful use of induced hydration requires an order of magnitude improvement in accuracy of hydration rim measurement over the accuracies currently claimed for optical microscopy. The results do not affect the validity of hydration dating based on archaeological correlations.     

Understanding Ustasa violence

The Independent State of Croatia (1941-1945) was a multi-ethnic entity in which a range of political and military powers cooperated with and fought against one another. No less complicated were the ruling Ustaa movement and its relationship with Nazi Germany and Fascist Italy. The persecution of the Serbs, the Jews, and the Roma in the Independent State of Croatia was marked by differences and similarities, which were reflected the decision-making process within the Ustaa leadership. Over time, this mass violence (and Ustaa decisions) moderated due to a variety of factors: the interethnic civil war, victim reactions, local factors, and the harvest. The Italians and Germans, however, also played a role in the persecution of the Serbs, Jews, and Roma in Croatia. Simplifying narratives of the Ustaa as marginal collaborationists and state-centered concepts of genocide are inadequate when it comes to explaining Ustaa violence.     

俄罗斯的华人移民——社会问卷调查研究

通过对俄国新、老华人移民的大规模问卷调查,旨在全面认识和了解俄国的华人移民状况及他们对所面临问题的看法。调查主要涉及的内容有移民经历、生活水平、职业和群体的力量、与俄罗斯社会的相互关系、关于俄罗斯的总体印象及未来计划等。     

Field data validation of an algorithm for computing obsidian effective hydration temperature

This paper describes an analysis to validate the effective hydration temperature (EHT) algorithm for obsidian [Rogers, A.K., 2007. Effective hydration temperature of obsidian: a diffusion-theory analysis of time-dependent hydration rates. J. Arch. Sci. 34, 656-665], using hourly temperature data from the Amargosa Desert Research Site near Beatty, NV. These data were used as input to a numerical model of the temperature-dependent diffusion process, and EHT was calculated yearly and for the aggregate. The same temperature data were processed to extract input parameters for the climatic model reported and used as input for EHT computation. EHT as computed from recorded hourly data was found to be within 1 °C of that computed from the climatic model. It is also shown that computed EHT differences between sites are not sensitive to whether air or surface temperature data are used, as long as they are used consistently; however, surface temperature data must be used if depth corrections are to be made.