Pleistocene archaeology and environments of the Free State, South Africa.

Pleistocene climate variability is often seen as a major cause of much of the evidence observed in the archaeological and palaeontological record of Africa. While continent-wide climate systems play an important role when testing pan-African human evolutionary processes, a more focused perspective centred on specific ecosystems at a regional level allows a detailed assessment of the different spatiotemporal scales of the proxies used to reconstruct past environments and the ways humans adapted to their change over time. Recent research in the arid interior of South Africa has provided insights into the availability of freshwater in the open landscape, which is a fundamental factor for human survival and the spatiotemporal distribution of which may have had a major influence on adaptive strategies.

Conversion Rates, Causes, and Preoperative Associated Factors in 3,411 Laparoscopic Appendectomies: Insights after Nearly Three Decades of Laparoscopy and an Analysis of the Learning Curve.

Introduction: Laparoscopic appendectomy is the current gold standard in treating acute appendicitis. Despite the low frequency of conversion to open surgery, it remains necessary in certain cases. Our primary outcome was to identify the conversion rate of laparoscopic appendectomy to open surgery and how this rate has changed over the learning curve.

Infrared spectral library of tooth enamel from African ungulates for accurate electron spin resonance dating.

Electron spin resonance coupled with uranium-series dating (ESR/U-series) of carbonate hydroxyapatite in tooth enamel is the main technique used to obtain age determinations from Pleistocene fossils beyond the range of radiocarbon dating. This chronological information allows to better understand diachronic change in the palaeontological record, especially with regard to the evolution of the genus Homo. Given the relative paucity of human teeth at palaeontological and archaeological localities, ESR/U-series is widely applied to the teeth of ungulate species.