1,721,227 research outputs found
Aterian lithic technology and settlement system in the Jebel Gharbi, North-Western Libya
No full textThe Aterian represents one of the multiple facets of the Middle Stone Age (MSA) and has become increasingly important in the context of understanding modern human origins. In this paper, we present the results of our study on the Aterian in the Jebel Gharbi, North-Western Libya, from a regional point perspective. A total of 1567 lithic objects were analysed for this work from twelve different Aterian assemblages. The results of this analysis show a wide range of economic behaviour, possibly suggesting different site functions, within the three main areas (Ain Zargha, Jefara and Wadi Ghan). It is unlikely that any of these assemblages represents a residential site. Instead, we argue that the assemblages in the study are more likely to be the result of a logistic land use. Technologically, they exhibit all the distinctive features of the Aterian technocomplexes: coexistence between Levallois and blade technology, presence of tanged pieces and bifacial foliates, as well as of “Upper Palaeolithic” tools, together with a majority of sidescrapers and endscrapers. Only a combination of these features, and certainly not one of them alone, can characterize an assemblage as “Aterian”
Identification and evaluation of post-depositional mechanical traces on quartz assemblages. An experimental investigation
No full textThe evaluation of the state of preservation of archaeological lithic artefacts is the first step before starting a functional analysis. If lithic artefacts show a variety of damage from many contact materials, they are also subject to modifications from “natural” causes, such as water transport, soil abrasion, trampling etc. Studying alteration features gives us information to reconstruct the life story of lithic tools after their abandonment and helps us to better understand formation processes of archaeological sites.
Prolonged movements under soil could be responsible for post depositional surface modifications that sometimes look like wear traces due to use. These alterations could have chemical and/or mechanical origin. Recognizing them is of paramount importance especially on quartz assemblages where usewear analysis requires a long and complex methodology that differs to a certain extent from the protocol applied to other artefacts produced with different raw materials such as flint, obsidian etc ... For this reason, the use wear and post-depositional surface modification analysis on quartz and quartzite tools have been undertaken by very few researchers until now. The aim of this paper is to increase the experimental quartz field through the attempt to recreate mechanical contact between quartz flakes and sediments such as in archaeological contexts.
Through the use of a Polishing Machine MECAPOL P320 equipped with two counter-rotating platens, it was possible to wear out two experimental flakes in a sandy quartzite sediment coming from Sai Island (Sudan) for 240 h.
After the experimentation, the two flakes showed no edge damage or other visible modifications, but some micro traces on the crystal surface were present. Although long and demanding, this step sharply reduces possible errors in the recognition of use-wear during the experimental stage. The micro traces definable as abrasions on some parts of the crystal surface, have been analysed by a metallographic microscope and compared with the same crystal portion taken before the experiment. Even if it is difficult to reconstruct post depositional processes in a laboratory, this attempt shows that the contact between sediment and stone tools in a continuous movement can randomly abrade the crystal surface
From settlement patterns to memory of place among Holocene hunter-gatherers at Sai Island, Middle Nile Valley
No full textPersistent places are the locations where people aggregate, utilise and reuse natural or built features and develop their social identities and interactions. A network of persistent places forms interconnected persistent settlement patterns, which create a humanly made or storied landscape with a shared community-based memory of place. Although it has been demonstrated that persistent settlement patterns long preceded the onset of Neolithic farming villages, the Levant has received the most attention regarding this perspective. At the same time, Africa still needs to be addressed. This paper provides an illustrative case study of persistent settlement patterns created by Holocene hunter-gatherers in the Middle Nile Valley of Sudan. It employs geostatistical patterning and visual mapping of an extensive collection of different classes of artefacts (lithic industry, hammerstones, ground stone tools and pottery) from a well-preserved Khartoum Variant site on Sai Island and correlates them to complex architectural features exposed on an archaeological surface (Level 1) at site 8-B-10C dating to the early fifth millennium cal. BC. The combination of multiple in-depth geostatistical analyses of a complex habitation system successfully documents an exceptionally preserved planned intra-site settlement organisation maintained over several generations, revealing a memory of place.Les lieux persistants sont les endroits où les gens se regroupent, utilisent et réutilisent les structures naturelles ou construites, et où ils développent leurs identités et interactions sociales. Un réseau de lieux persistants forme à son tour des modes de peuplement persistants et interconnectés, ce qui crée un paysage anthropique ou marqué par des histoires, avec une mémoire du lieu qui est partagée par la communauté. Bien qu’il ait été démontré que les modes de peuplement persistant ont précédé de longtemps l’apparition des villages agricoles néolithiques, le Levant a reçu la plus grande attention dans cette perspective, tandis que l’Afrique a été négligée. Cet article présente une étude de cas illustratif sur les modes d’établissement persistants créés par les chasseurs-cueilleurs de l’Holocène dans la vallée moyenne du Nil. Nous utilisons des modèles géostatistiques et la cartographie visuelle d’une vaste collection de différentes classes d’artefacts (industrie lithique, percuteurs, outils en pierre polie et poterie) provenant d’un site bien préservé du ‘Khartoum Variant’ sur l’île de Sai, et les mettons en corrélation avec des structures architecturales complexes exposées sur une surface archéologique (niveau 1) sur le site 8-B-10C, qui date du début du cinquième millénaire calibrée avant J.-C. La combinaison d’analyses géostatistiques multiples et approfondies d’un système d’habitation complexe documente avec succès une organisation planifiée de l’habitat à l’échelle du site qui est exceptionnellement préservée et qui fut maintenue sur plusieurs générations, révélant une mémoire du lieu
Palynological evidence of cultural and environmental connections in Sudanese Nubia during the Early and Middle Holocene
No full textPollen and non-pollen palynomorphs have been studied from three archaeological sites (8-B-10C, 8-B-76,
and 8-B-81) on Sai Island, in the River Nile, and one (2-R-66) from the Amara West district, in northern
Upper Nubia of the present Sudan. The research aimed at obtaining information on the environmental
conditions and changes occurring in the area during the Early and Middle Holocene. Archaeologically,
this is a crucial period as it saw one of the most relevant economic transitions from huntingefishing
egathering to animal herding. The archaeopalynological analyses are useful to reconstruct the environment
and plant landscapes that supported human plant selection in this part of North Africa, between
about 8700 and 4300 cal BC. However, pollen was not present everywhere because the sediments were
very poor in organic content, or damaged by the repeated hydrationedehydration cycles determined by
the Nile river floodings. The data obtained, the most consistent from any archaeological site in this area,
are coherent with the regional and interregional palaeoenvironmental data. The interdisciplinary studies
that allowed the correct interpretation of the pollen records presented in this paper included the
archaeological features, and the faunal (mainly gastropod) and algal remains from the same sites. The
state of preservation of most pollen, showing thinned exine, and the remarkable records of the terrestrial
alga Fritschiella outline the seasonality of the area that has been evident in the past as in the present.
Pollen samples included prevailing amounts of grasses and sedges that, with some hygro-hydrophilous
taxa, largely represent the riverine and wetland vegetation of the Nile Valley. They suggest that the land
use was not intensive and was not able to substantially modify the natural cover and cyclic renewal of the
soils and the vegetation. The interdisciplinary evidence from the Sai Island, showing that site 8-B-76 has
been continuatively occupied during the 8.2 ka BP dry phase, proves the key role played by the great
river on attracting humans and supplying resources even, and especially, during the arid oscillations of
the Holocene.Pollen and non-pollen palynomorphs have been studied from three archaeological sites (8-B-10C, 8-B-76, and 8-B-81) on Sai Island, in the River Nile, and one (2-R-66) from the Amara West district, in northern Upper Nubia of the present Sudan. The research aimed at obtaining information on the environmental conditions and changes occurring in the area during the Early and Middle Holocene. Archaeologically, this is a crucial period as it saw one of the most relevant economic transitions from hunting–fishing–gathering to animal herding. The archaeopalynological analyses are useful to reconstruct the environment and plant landscapes that supported human plant selection in this part of North Africa, between about 8700 and 4300 cal BC. However, pollen was not present everywhere because the sediments were very poor in organic content, or damaged by the repeated hydration–dehydration cycles determined by the Nile river floodings. The data obtained, the most consistent from any archaeological site in this area, are coherent with the regional and interregional palaeoenvironmental data. The interdisciplinary studies that allowed the correct interpretation of the pollen records presented in this paper included the archaeological features, and the faunal (mainly gastropod) and algal remains from the same sites. The state of preservation of most pollen, showing thinned exine, and the remarkable records of the terrestrial alga Fritschiella outline the seasonality of the area that has been evident in the past as in the present. Pollen samples included prevailing amounts of grasses and sedges that, with some hygro-hydrophilous taxa, largely represent the riverine and wetland vegetation of the Nile Valley. They suggest that the land use was not intensive and was not able to substantially modify the natural cover and cyclic renewal of the soils and the vegetation. The interdisciplinary evidence from the Sai Island, showing that site 8-B-76 has been continuatively occupied during the 8.2 ka BP dry phase, proves the key role played by the great river on attracting humans and supplying resources even, and especially, during the arid oscillations of the Holocene
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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