1,720,980 research outputs found
Etnobotanica di Citrullus colocynthis (L.) Schrader quale risorsa utilizzata dagli abitanti della zona sahariana
No full textDa sempre, l’utilizzo di piante da parte delle popolazioni che vivono in ambienti desertici comprende la maggior parte delle specie reperibili sul territorio, incluse quelle considerate “tossiche”, e oggigiorno queste conoscenze costituiscono fonte di interesse per la possibilità di ottenere conferme e nuove informazioni sulla validità del loro uso farmacologico e alimentare. La coloquintide (Citrullus colocynthis) è una pianta erbacea che cresce spontanea su substrati sabbiosi di aree desertiche e semi-desertiche, in tutto il Sahara, nelle regioni subtropicali e nel bacino mediterraneo, fino a raggiungere il Medio Oriente, Iran, India e Asia meridionale. Questa pianta, citata nella Bibbia e nei papiri di Ebers (c. 1550 a.C.) per le sue proprietà curative e per la sua pericolosità è ancora oggi utilizzata tradizionalmente. I caratteristici semi di Citrullus colocynthis sono stati ritrovati in diversi siti archeologici sahariani, a testimonianza di un uso antico e radicato nelle tradizioni locali
Burning without slashing. Cultural and environmental implications of a traditional charcoal making technology in the central Sahara
No full textWe describe in this paper a traditional charcoal making technology occasionally adopted by Tuareg people in the hyper-arid central Sahara (SW Libya). This methodology (called esed) has been identified thanks to ethnobotanic and ethnographic interviews with people living in the Tadrart Acacus massif (the kel Tadrart Tuareg) and confirmed by macroscopic and micromorphological analyses of residual field evidence. Esed consisted of burning in situ trunks of dead Acacia tortilis (Forssk.) Hayne; subsequently, small portions of collapsed and still-burning wood were buried with sand in an attempt to ensure combustion under anoxic conditions. Our interviews elucidated that the esed technology is well known by people living in the region and has possibly been practiced for a long time. Surprisingly, local informants highlighted that esed was employed to made charcoal only during years marked by abrupt reduction of precipitation and consequently of natural resources. The last employment of esed dates to the dry phase of the mid-1970s, when charcoal was used as an exchangeable good. The discovery of this charcoal making technology shed new light on the capability of Tuareg to manage the few natural resources available in marginal environments and to cope with rapid climate changes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
On-site pollen data from Takarkori rockshelter: inferences on the Holocene landscape of the Central Sahara
No full textArchaeobotanical studies on pollen and macro-remains, carried out within a multidisciplinary research framework, provided information on the past human-environment relationships and on the Holocene landscape evolution of Central Sahara. This has been repetitively obtained by the studies on rockshelters and caves which are widely distributed in this desert region. The site of Takarkori is a large rockshelter with a well preserved stratigraphic series located in the Acacus Mts. (south-western Libya, central Sahara), not far from the Algerian border. The excavations were carried out from 2003 to 2006 over a surface of ca. 120 square metres, and brought to light occupation levels radiocarbon dated between ca. 4500 and 8900 uncal. years bp. A sounding was done in the northern part of the site, in order to check the entire sequence. Here, around 140 cm of sandy sediment were excavated, testifying for a human occupation related to Late Acacus (“Mesolithic”), and to Early and Middle Pastoral Neolithic contexts. The palynological sequence has been mainly sampled on the southern wall of the sounding. There are 5 units, from the top containing different quantities of undecomposed straw, coprolites and hearths (Units I and II, Middle Pastoral), and then humified and loose layers (from Unit III-Early Pastoral, to Unit IV-V-Late Acacus). As the Early Pastoral and the Late Pastoral layers are not well preserved in this part of the site, other sediment samples have been collected in specific contexts, in order to balance this bias. The on-site pollen series consists of 30 samples. Pollen was common and better preserved in the bottom samples, from 80 to 140 cm deep, than in others. Pollen clusters, especially of Poaceae, phytoliths and microcharcoals were common. The pollen list includes about 90 taxa, representing a fairly high biodiversity. Obviously, most pollen was transported and accumulated into the shelter by humans. Nevertheless, the anthropogenic pollen accumulation is well distinguishable as generally concentrations are very high. In the different samples, main changes in the pollen list match changes in the local flora. Moreover, pollen curves of Poaceae and Chenopodiaceae clearly mark the decrease of savanna and the increase of desert communities in this region of Central Sahara, at the passage from the early Holocene towards the latest part of the middle Holocene. Studies on seeds/fruits, wood/charcoal, coprolites, plant ropes and baskets support the landscape reconstructions obtained by pollen spectra
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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