The archaeology of rock art in Northern Africa

The first reports on the rock art of north Africa were written in the mid-nineteenth century. Since then, rock art has become a key area of African archaeological research. Commencing with a short background on the environmental setting, this chapter reviews past research and major theoretical perspectives through to the present, highlighting contributions to wider debates. The main geographical, temporal, and archaeological frameworks of north African rock art are summarized in broad chronological order, beginning with late Pleistocene engravings up to ‘Camel art’ of more recent, historical age. Despite current hurdles faced in today’s research environment, rock art studies are of great importance in north Africa, especially when undertaken by African scholars. This precious, irreplaceable, nonrenewable cultural resource is of great educational value, and its preservation, teaching, and dissemination may contribute to a renewed awareness of the cultural value of rock art for future generations

Three-dimensional advanced numerical approaches to the seismic soil and structural response analyses

A 3D non-linear finite element approach is developed to study the free-field seismic ground response and the soil-structure interaction (SSI) phenomena at the Lotung site (Taiwan) during the earthquake event occurred on May 20 1986. The site was extensively instrumented with down-hole and surface ac- celerometers, these latter located also on a 1/4–scale nuclear power plant containment structure. An advanced constitutive model is adopt- ed for simulating the soil behaviour, while a linear visco-elastic be- haviour is assumed for the structural model. The free-field and SSI analyses are carried out applying both the NS and EW horizontal components of the acceleration time history as recorded at the depth of 47 m b.g.l. The predicted ground response re- sults are in fair agreement with the recorded motion at depth and at the surface. The dynamic response of structure is well captured for this specific seismic event, thus confirming the validity of the numerical approach

Psoriasis Area and Severity Index response in moderate-severe psoriatic patients switched to adalimumab: results from the OPPSA study

Background: Few studies have compared the efficacy of switching to adalimumab in the real-life setting in plaque psoriasis patients. Objective: To evaluate the effect of adalimumab in psoriasis patients previously treated with other biologics. Methods: In this multicentre study, psoriasis patients (N = 262) treated with an anti-TNF-alpha agent, ustekinumab or naïve to biologics then switched to adalimumab were included. Disease severity was assessed by the Psoriasis Area and Severity Index (PASI) at baseline and after 3, 6, 12, 24 and 36 months. The association between clinical risk factors and achievement of PASI response was evaluated by logistic regression. Results: Adalimumab treatment resulted in a decrease in PASI (15.1 ± 6.2 at baseline vs. 2.7 ± 4.8 at 6 months, P < 0.0001), regardless of previous biologic treatment. Furthermore, adalimumab allowed 92.5%, 79% and 56% of patients to achieve PASI response (PASI 50, 75 and 90, respectively) and complete remission (PASI 100 response) in 48.4% of patients, by 6 months and maintained over 3 years, independent of prior biologic treatment. The absence of metabolic syndrome, dyslipidemia, hypertension and lower PASI and lower age at baseline was associated with achievement of PASI response at 3, 6 and 12 months, whereas at later time points (24 and 36 months), PASI 90 and PASI 100 response was associated with diagnosis of psoriasis/psoriatic arthritis. Conclusion: Adalimumab was effective at reducing PASI score over 3 years, irrespective of whether patients were biologic naïve or previously treated with a TNF-alpha or IL-12/23 inhibitor

MULTIDISCIPLINARY INVESTIGATION ON EARLY-MID HOLOCENE WILD CEREALS FOUND AT TAKARKORI (CENTRAL SAHARA)

Plant macroremains from rock shelters of central Sahara give information about the environmental conditions during the Holocene, and the adaptive strategies of human groups living in the area. Takarkori was excavated by the Italian-Libyan Archaeological Mission in the Acacus and Messak (directed by S. di Lernia, Sapienza University of Rome) and its chronology ranges from ca. 10,200 to ca. 4,600 cal yr BP (Cremaschi et al. 2014)

Earliest direct evidence of plant processing in prehistoric Saharan pottery

The invention of thermally resistant ceramic cooking vessels around 15,000 years ago was a major advance in human diet and nutrition(1-3), opening up new food groups and preparation techniques. Previous investigations of lipid biomarkers contained in food residues have routinely demonstrated the importance of prehistoric cooking pots for the processing of animal products across the world(4). Remarkably, however, direct evidence for plant processing in prehistoric pottery has not been forthcoming, despite the potential to cook otherwise unpalatable or even toxic plants(2,5). In North Africa, archaeobotanical evidence of charred and desiccated plant organs denotes that Early Holocene hunter-gatherers routinely exploited a wide range of plant resources(6). Here, we reveal the earliest direct evidence for plant processing in pottery globally, from the sites of Takarkori and Uan Afuda in the Libyan Sahara, dated to 8200-6400 bc. Characteristic carbon number distributions and \u3b4(13)C values for plant wax-derived n-alkanes and alkanoic acids indicate sustained and systematic processing of C3/C4 grasses and aquatic plants, gathered from the savannahs and lakes in the Early to Middle Holocene green Sahara

Multidisciplinary analysis of Early \u2013 Mid Holocene wild cereal remains from central Sahara (SW Libya).

.Pollen and plant macroremains from rock shelters of central Sahara give information about environmental conditions during the Holocene, and adaptive strategies of human groups living in the area. Wild cereals were long-time exploited and are prevalent among plants selected and transported to these sites. Spikelets and grains of Panicoideae are the most abundant plant remains found at Takarkori, a rock shelter in the Tadrart Acacus Mts. (SW Libya). They have been studied by means of morphological and molecular (ancient DNA) analyses. The excavation by the Italian-Libyan Archaeological Mission in the Acacus and Messak (Sapienza University of Rome and Libyan Department of Archaeology) exposed a surface of 140 m2. The deposit includes stone structures, fireplaces, plant accumulations and a burial area. The site (dated 10,200-4,600 cal yr BP) was occupied throughout Early and Middle Holocene, a pivotal period for human development as include the transition from hunter-gatherer subsistence to food production. Peculiarity of the sequences is the surprising preservation of organic matter. Systematic morphobiometrical analysis was carried out on 1,450 spikelets of Panicum, Echinochloa and Sorghum selected on the basis of their different cultural contexts. The records showed uniform size in each genus. aDNA was extracted testing different protocols and then was studied by the DNA barcoding technique using four chloroplast markers. Bioinformatic analysis of the results allowed to inspect the phylogenetic relationships between the archaeobotanical records and the modern species of African wild cereals

VOF Simulation of The Cavitating Flow in High Pressure GDI Injectors

The paper describes the development in the OpenFOAM ® technology of a dynamic multiphase Volume-of-Fluid (VoF) solver, supporting mesh handling with topological changes, that has been used for the study of the physics of the primary jet breakup and of the flow disturbance induced by the nozzle geometry during the injector opening event in high-pressure Gasoline Direct Injection (GDI) engines. Turbulence modeling based on a scale-resolving approach has been applied, while phase change of fuel is accounted by means of a cavitation model that has been coupled with the VOF solver. Simulations have been carried out on a 6-hole prototype injector, especially developed for investigations in the framework of the collaborative project FUI MAGIE and provided by Continental Automotive SAS. Special attention has been paid to the domain decomposition strategy and to the code development of the solver, to ensure good load balancing and to minimize inter-processor communication, to achieve good performance and also high scalability on large computing clusters

Multidisciplinary analysis of wild cereals from the Holocene archaeological site of Takarkori (central Sahara)

Pollen and plant macroremains from central Sahara archaeological sites give information about the environmental conditions during the Holocene and the adaptive strategies of human groups living in the area . Wild cereals have been exploited for long time and are the prevalent taxa among those selected and transported to shelters and caves. The extraordinary state of preservation of the organic materials found at Takarkori allowed the morphological and molecular analyses of seeds/fruits belonging to the Poaceae family

Wild cereals from Holocene central Sahara archaeological sites: aDNA and archaeobotany from the Takarkori rockshelter

Both pollen and macroremains recovered from archaeological sites point to a long-time exploitation of wild cereals and to the prevalence of these plants among those selected and transported to shelters and caves of central Sahara (southwestern Libya)(1). Spikelets, florets and grains of Panicoideae (Brachiaria, Cenchrus, Echinochloa, Panicum, Setaria, Urochloa, Sorghum) are the most abundant plant remains in these sites. The archaeological excavation of the Takarkori rockshelter by the Italian-Libyan Archaeological Mission in the Acacus and Messak (Central Sahara), Sapienza University of Rome (directed by S. di Lernia), exposed a surface of c. 120 m2 in extent. The 1.6 m thick deposit includes stone structures, fireplaces, plant accumulations, dung layers and a burial area. Layers were deposited during hunter-gatherer and later pastoralist occupational phases. Chronology ranged from c. 9000 to 4200 BP, and was based on stratigraphy, radiocarbon dates, and archaeological materials (2). Systematic morphological analysis was carried out on 200 spikelets/florets selected as representative of different chronological contexts. The records of Panicum, Echinochloa and Sorghum showed homogeneous typology and fairly uniform size in each genus. aDNA extraction confirming the morphological identifications of the three taxa was obtained by Olmi et al. (3). aDNA was successfully performed using several methods (4, 5) and then assayed using PCR with a primer set for the rbcL gene. New aDNA extraction was obtained from Panicum spikelets and the analysis of matK, trnH-psbA and trnL barcode regions may help to identify the records at species level

Inside the "African Cattle Complex": Animal Burials in the Holocene Central Sahara

Cattle pastoralism is an important trait of African cultures. Ethnographic studies describe the central role played by domestic cattle within many societies, highlighting its social and ideological values well beyond its mere function as 'walking larder'. Historical depth of this African legacy has been repeatedly assessed in an archaeological perspective, mostly emphasizing a continental vision. Nevertheless, in- depth site-specific studies, with a few exceptions, are lacking. Despite the long tradition of a multi-disciplinary approach to the analysis of pastoral systems in Africa, rarely do early and middle Holocene archaeological contexts feature in the same area the combination of settlement, ceremonial and rock art features so as to be multi- dimensionally explored: the Messak plateau in the Libyan central Sahara represents an outstanding exception. Known for its rich Pleistocene occupation and abundant Holocene rock art, the region, through our research, has also shown to preserve the material evidence of a complex ritual dated to the Middle Pastoral (6080-5120 BP or 5200-3800 BC). This was centred on the frequent deposition in stone monuments of disarticulated animal remains, mostly cattle. Animal burials are known also from other African contexts, but regional extent of the phenomenon, state of preservation of monuments, and associated rock art makes the Messak case unique. GIS analysis, excavation data, radiocarbon dating, zooarchaeological and isotopic (Sr, C, O) analyses of animal remains and botanical data are used to explore this highly formalized ritual and lifestyles of a pastoral community in the Holocene Sahara