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While the use of fire has long been recognised as a crucial innovation in the cultural evolution of humankind, much research has focused on the (debated) chronology of its earliest use and control, and less on the ways in which fire was used in the deep past. At its latest by the Upper Palaeolithic, hunter-gatherers routinely used fire to heat a wide range of materials, adjusting parameters like temperature, exposure time and fuel type to the specific requirements of the treated materials, for instance in food preparation or tool production. Comparing analyses of the chemical and physical properties of modern materials, heated under a range of controlled conditions in a laboratory, to archaeological ones might allow the reconstruction of the “heating history” of excavated materials and hence to infer the function of particular fires in the past - provided changes affecting the properties of the heated archaeological material during burial time are taken into consideration. To investigate the feasibility of such an approach, heated materials sampled from ~40,000 to 25,000 year old fireplaces (hearths) and their sedimentary matrices from the Upper Palaeolithic Abri Pataud rock shelter in South-Western France are used here to study (1) the fuel type(s) used by the site's occupants, (2) the temperatures reached in fireplaces and (3) the potential changes in human activities related to fireplaces over time, with the influence of post-depositional processes taken into explicit consideration throughout. For this purpose, we used a range of methods to analyse macroscopically visible as well as “invisible” (microscopic and molecular) heat-altered materials. The results suggest that charred organic materials (COM) encountered in the samples predominantly result from the fuel used in fireplaces, including the earliest reported use of dung as fuel. Earlier suggestions about the use of bone as fuel at the Abri Pataud are not supported by this study. The heating temperature of

While the use of fire has long been recognised as a crucial innovation in the cultural evolution of humankind, much research has focused on the (debated) chronology of its earliest use and control, and less on the ways in which fire was used in the deep past. At its latest by the Upper Palaeolithic, hunter-gatherers routinely used fire to heat a wide range of materials, adjusting parameters like temperature, exposure time and fuel type to the specific requirements of the treated materials, for instance in food preparation or tool production. Comparing analyses of the chemical and physical properties of modern materials, heated under a range of controlled conditions in a laboratory, to archaeological ones might allow the reconstruction of the “heating history” of excavated materials and hence to infer the function of particular fires in the past - provided changes affecting the properties of the heated archaeological material during burial time are taken into consideration. To investigate the feasibility of such an approach, heated materials sampled from ~40,000 to 25,000 year old fireplaces (hearths) and their sedimentary matrices from the Upper Palaeolithic Abri Pataud rock shelter in South-Western France are used here to study (1) the fuel type(s) used by the site’s occupants, (2) the temperatures reached in fireplaces and (3) the potential changes in human activities related to fireplaces over time, with the influence of post-depositional processes taken into explicit consideration throughout. For this purpose, we used a range of methods to analyse macroscopically visible as well as “invisible” (microscopic and molecular) heat-altered materials. The results suggest that charred organic materials (COM) encountered in the samples predominantly result from the fuel used in fireplaces, including the earliest reported use of dung as fuel. Earlier suggestions about the use of bone as fuel at the Abri Pataud are not supported by this study. The heating temperature of CO

To date, the earliest modern human fossils found outside of Africa are dated to around 90,000 to 120,000 years ago at the Levantine sites of Skhul and Qafzeh. A maxilla and associated dentition recently discovered at Misliya Cave, Israel, was dated to 177,000 to 194,000 years ago, suggesting that members of the Homo sapiens clade left Africa earlier than previously thought. This finding changes our view on modern human dispersal and is consistent with recent genetic studies, which have posited the possibility of an earlier dispersal of Homo sapiens around 220,000 years ago. The Misliya maxilla is associated with full-fledged Levallois technology in the Levant, suggesting that the emergence of this technology is linked to the appearance of Homo sapiens in the region, as has been documented in Africa.

В статті розглянуто вплив присадок на зовнішньо-швидкісні характеристики дизелів, що працюють в нестаціонарних умовах. Виявлено збільшення рівня потужності та крутного моменту і зниження питомої витрати палива при додаванні присадок дисульфід молібдена, "НИОД-5", "Roil Gold, і "КГМТ-1" запропонованої авторами. Отримані результати обґрунтовуються впливом присадок на характеристики та властивості моторної оливи, її зношувальну здатність та припрацьованість основних спряжень дизелі. Визначено також відновлюваний характер властивостей оливи при додаванні присадок, що підтверджують експериментальні дослідження зміни моменту тертя з напрацюванням в різних режимах функціонування: безперервному і "пуск-зупинка". The article considers the influence of additives on the externally-speed characteristics of diesel engines operating under transient conditions. Investigations were carried out on the break-in-roller stand КС-276-032 to validate the running-in and testing of diesel engines in the cold no-load and hot  load and no load. Testing procedures and evaluate the performance of the engine. In the basic engine oil added various functional additives in optimum concentrations. Speed range crankshaft commensurate with the operational range. Tests were carried out in a continuous mode, and the "start-stop". Revealed that the addition of molybdenum disulphide additives, "НИОД-5", "Roil Gold", and "КГМТ-1" suggested by the authors, increased levels of power and torque and reduced fuel consumption. The findings substantiate the influence of additives on the characteristics and properties of the engine oil, it wears capacity and runningmates main diesel. Restorative properties of the oil with the addition of additives, is supported by experimental studies of changes in the friction torque with operating in different modes of operation: continuous and "start-stop". In the used motor oil without making the test additives friction torque peaks recorded in a continuous mode and in the "

В статті наведено результати впливу різних присадок на зміну моменту тертя спряжених зразків "ролик-колодочка" змащених базовою та композиційною моторною оливою М10Г2к на машині тертя СМЦ-2. Дослідження проведені в безперервному та "пуск-зупинка" режимі. Виявлено, що при додаванні присадок "НИОД-5", "Roil Gold", "КГМТ-1" до моторної оливи М10Г2к зменшується рівень і ширина піку моменту тертя на першому інтервалі і зниження піків моменту тертя на решта інтервалах випробувань. Встановлено, що моментом тертя спряжених зразків та деталей, які працюють на моторній оливі М10Г2к, можна керувати, а спрацьовану моторну оливу – відновлювати при її модифікуванні присадкою. The article describes the effects of various additives to replace the friction torque coupled models "roller-block" base lubricants and motor oils compositional M10Г2к on the friction machine СМЦ-2. Studies conducted in a continuous and "start-stop" mode. We found that the addition of additives "Ниод-5", "Roil Gold", "КГМТ-1" to the motor oil M10Г2к reduced level and the peak width of the first friction torque range and lower peak friction torque test on the remaining intervals. Found that the friction factor conjugate samples and components that run on motor oil M10Г2к can be handled and worn motor oil – restore it at modifying additive.

В статті виявлено вплив умов експлуатації на зміну фізико-хімічних показників базових моторних олив дизелів автосамоскидів, наведена схема причинно-наслідкових зв'язків цієї зміни. Дано результати досліджень зміни коксівності, густини оливи від терміну експлуатації, показано зміну концентрації хімічних елементів в ній. Встановлено, що ресурсом кар'єрних автосамоскидів можна управляти та збільшувати інтервал ТО, здійснюючи модифікуючий вплив на моторну оливу додаванням присадок та обробкою фізичним полем. Influence of external on the changes of physical and chemical indexes of base motor oil of diesels of dumper environments, the brought chart over of relationship of cause connections of these changes, is educed in the article. The results of researches of change of coked, closenesses of oil, are given from the term of exploitation, the change of concentration of chemical elements is shown in him. It is set that it is possible to manage the resource of quarry dumper and increase an interval maintenance, carrying out modifying influence on motor oil addition of additives and treatment the physical field.

Although a rich record of Pleistocene human-associated archaeological assemblages exists, the scarcity of hominin fossils often impedes the understanding of which hominins occupied a site. Using targeted enrichment of mitochondrial DNA we show that cave sediments represent a rich source of ancient mammalian DNA that often includes traces of hominin DNA, even at sites and in layers where no hominin remains have been discovered. By automation-assisted screening of numerous sediment samples we detect Neandertal DNA in eight archaeological layers from four caves in Eurasia. In Denisova Cave we retrieved Denisovan DNA in a Middle Pleistocene layer near the bottom of the stratigraphy. Our work opens the possibility to detect the presence of hominin groups at sites and in areas where no skeletal remains are found.