Heat treatment significantly increases the sharpness of silcrete stone tools

Humans were regularly heat-treating stone tool raw materials as early as 130,000 years ago. The late Middle Stone Age (MSA) and Late Stone Age (LSA) of South Africa's Western Cape region provides some of the earliest and most pervasive archaeological evidence for this behaviour. While archaeologists are beginning to understand the flaking implications of raw material heat treatment, its potential functional benefits remain unanswered. Using silcrete from the Western Cape region, we investigate the impact of heat treatment on stone tool cutting performance. We quantify the sharpness of silcrete in its natural, unheated form, before comparing it with silcrete heated in three different conditions. Results show that heat-treated silcrete can be significantly sharper than unheated alternatives, with cutting forces halving and energy requirements reducing by approximately two-thirds. The data suggest that silcrete may have been heat treated during the South African MSA and LSA to increase the sharpness and performance of stone cutting edges. This early example of material engineering has implications for understanding Stone Age populations’ technological capabilities, inventiveness and raw material choices. We predict that heat-treatment behaviours in other prehistoric and ethnographic contexts may also be linked to increases in edge sharpness and concerns about functional performance

Gender and Educational Differences in Perception of Domestic Violence Against Women Among Libyan Migrants in Manchester.

Domestic violence against women (DVAW) is a worldwide phenomenon and refers to any act committed against women that results in physical and psychological harm, and coercion, loss of liberty, and deprivation. There is a dearth of research and information about the extent and prevalence of domestic violence among Libyan communities. The aim of the study was to explore community knowledge of, and attitudes toward, DVAW and to improve our understanding of the factors that influence knowledge, attitudes, and responses, particularly educational and gender differences. Using snowball sampling, we analyzed 20 semistructured interviews with Libyans living in Manchester, United Kingdom. We found gender and education-influenced participants' perception of DVAW. Men in general did not recognize DVAW as a serious social problem; noticeably, they saw it as a personal and family issue. Knowing attitudes toward DVAW is necessary for government and communities' prevention policies as attitudes influence perpetration of DVAW

Archaeological Reconnaissance for Middle Stone Age Sites Along the Pondoland Coast, South Africa

This paper summarizes the results of a recent survey of the South African “Wild Coast” in Pondoland, Eastern Cape Province. The purpose of the survey was to locate and to describe coastal caves and rock shelters that may contain Early and Middle Stone Age archaeological deposits for future study. The study is part of a much larger research design to understand three basic and interlinked paleoanthropological questions: When did coastal intertidal foraging develop? How did it develop? What role did coastal intertidal foods have on the evolution and survival of early modern humans? Here, we provide the full results of our multi-disciplinary survey. We describe the archaeology, geology, marine, and terrestrial fauna from four near-coastal rock shelters and one coastal open-air site that we intend to test in the future. We also provide the first direct ages of the coastal red sands that contain in situ Early Stone Age Acheulian and early Middle Stone Age flaked stone tools. These optically stimulated luminescence ages show that humans have inhabited Pondoland for over 300,000 years, predating the currently known origins of the modern human lineage and systematic coastal foraging. We also describe the first dated paleoenvironmental sequences for Pondoland, which suggest a shift from C3 to C4 vegetation during the middle Holocene. Lastly, we provide comprehensive notes on all sites in Supplementary Online Materials to benefit future studies across the region and document an area that has seen very limited archaeological researchPart of the phytolith analysis was supported by the Ministerio de Ciencia e Innovación (HAR2010-15967 to Albert). The field survey was funded by a grant from the National Geographic Society / Waitt Foundation (W160-11 to Fisher)Peer reviewe

Performance of Ti/Zr and silane coating pretreatments on adhesive bonding of an automotive aluminium alloy produced using the Hot Form Quench (HFQ®) process

Surface pretreatments of an automotive aluminium alloy delivered in F temper and subsequently processed using Hot Form Quench (HFQ®), a novel press forming technique combining solution heat treatment, press forming and in-die quenching to produce high-strength aluminium alloys, for adhesive bonding have been explored. The performance of two commercial pretreatments including Ti/Zr and silane coatings, with either acid spray or alkaline immersion cleaning, was investigated. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) were employed to characterize the surface chemistry and topography of the alloy after pretreatments. Adhesively bonded aluminium-aluminium single lap shear joints and double cantilever beam specimens were tested to evaluate the performance of the pretreatments on the bonding strength and fracture resistance, respectively. The FTIR and TEM techniques show that the natural oxides and near-surface deformed layer have been successfully removed, but the surface cleanliness level was sensitive to the cleaning approach adopted. New Ti/Zr oxide layers or silane films have been built upon the aluminium surfaces, which confirms that sound surface conditions for adhesive bonding can be obtained for parts produced using HFQ® from F temper input material

Plant-wax and phytolith data from Waterfall Bluff rock shelter

Waterfall Bluff, in Eastern Mpondoland (Eastern Cape Province, South Africa), is a recently excavated archaeological site with deposits spanning Marine Isotope Stage (MIS) 3 to the Middle Holocene. Here, we present preliminary results of a multi-proxy palaeoenvironmental study combining macro-botanical remains, charcoal, phytoliths, pollen and plant waxes derived from the same archaeological record. We aim to understand the interactions between hunter-gatherer plant foraging and climate and environmental change in coastal Mpondoland from MIS 3 to the Early Holocene at Waterfall Bluff. The charcoal and pollen records at Waterfall Bluff show the gathering of a variety of woody taxa characterised by their combustion and medicinal properties (e.g., Millettia grandis and Apodytes dimidiate). The leaves identified in the macrobotanics and in the phytolith record might belong to some of these taxa and it is likely that they were used for medicinal purposes. From a palaeoenvironmental perspective, our results indicate low precipitation and low rainfall seasonality under cool conditions during MIS 3 and the Last Glacial Maximum (LGM). Under these conditions, open woodlands interspersed with dry and hygrophilous grasslands and bushveld vegetation with significant representation of fynbos elements occurred in the local landscapes probably along Podocarpus/Afrocarpus forests. The latter could have been (1) present along river valleys and scarps on the Mpondoland exposed continental shelf towards the south and west of Waterfall Bluff, supported by palaeorivers and cool temperatures favouring low evapotranspiration, or (2) present in the interior with pollen grains possibly transported to the site by intensified westerly winds. These forests contracted as a result of the post-glacial marine transgression or reduced westerlies following the LGM. During the Early Holocene, the palaeoenvironmental signal points to higher summer rainfall and higher seasonality than during MIS 3, the LGM and the LGIT. These changes are coeval with an increase of coastal forests and C4 mesic grasslands with localized wetland vegetation around Waterfall Bluff. These multi-proxy archaeobotanical and biochemical data show that landscapes surrounding Waterfall Bluff changed in relation to marine transgressions/regressions and changes in rainfall intensity and seasonality. The people of Waterfall Bluff foraged the coasts during glacial periods to collect wood