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131.
Some of the most notable and largely endangered archaeological remains from the Lake Chad area consist of the ruins of fired-brick elite constructions connected to the Kanem-Borno Empire (ca. eighth–nineteenth century AD). In the course of the last 200 years, several of the elite structures known west of the lake were destroyed as a consequence of war, later having their fired-bricks looted for constructions elsewhere. One of the largest and most thoroughly plundered of those structures once stood within the walled settlement of Garumele, SW Niger Republic. In the scope of an experimental field study at that location and with a view to future work at related sites, we demonstrate that it is still possible to retrace the ground plans of Kanem-Borno fired-brick structures, even if these have been already completely pillaged. In addition, we present new chronological evidence suggesting that Garumele—as a walled urban settlement—was founded sometime between the mid-fifteenth and mid-seventeenth centuries, but most probably between the late sixteenth to mid-seventeenth centuries AD.  相似文献   
132.
The Aterian lithic techno-complex that characterizes the late Middle Stone Age in North Africa is well known especially for its tanged or stemmed points. Recent techno-morphological and use-wear analyses have added new data to support the identification of the tang as the hafted portion of an artifact. They have also highlighted the presence of this attribute on tools other than projectile points, in contrast with the widespread idea that the tanged point is the Aterian fossile directeur. The design of this specific device, the tang, for hafting purposes is regarded as a great technical innovation that underlines a modern behavior. Our work provides new use-wear and experimental data, aiming at discussing the cognitive preconditions of this technical innovation that could have originated from a specific functional unit: the notch. Notches are quite abundant in the Aterian techno-complex. Our systematic study of this tool category from Aterian sites of the Jebel Gharbi allowed defining the notch per se as a techno-morpho-functional unit that was “applied” to different types of blanks, including “reused blanks,” which show a heavy patina on their surface. This functional unit has been used for various types of activities and can be found either alone on a blank or with multiple other units on the same blank, creating different tool morphologies. According to this interpretation, the tang could have been considered by Aterian populations as a new resulting variant of various possible combinations of notches, for defining and/or transforming the shape of a tool.  相似文献   
133.
There is limited available data on the environmental context of the arrival of the first anatomically modern humans (AMH) in North Africa, and subsequent Paleolithic and Neolithic occupations within this region. Microvertebrates such as rodents, shrews, amphibians, and squamates are known to be good indicators of climate and landscape changes. They also represent continental paleoecological records that can be directly related to human occupations. Moreover, faunas and humans have been subjected to several dispersal waves through similar routes, and some rodents may present anthropophilous behavior. Therefore, by understanding the dispersal pattern and pathways of these microvertebrates, it is possible to propose scenarios for human dispersal events. In this study we took the rich microfaunal assemblages from the Témara region, Atlantic Morocco (El Harhoura 2 and El Mnasra Caves), and placed them within a broader synthesis, in order to highlight the role of microvertebrates in providing a better understanding of the human-environment relationship during the Late Quaternary in North Africa.  相似文献   
134.
The Rabat-Témara region of the Moroccan Atlantic coast reveals a succession of Quaternary palaeobeaches. This coastal area is dotted with numerous prehistoric caves. The study of the Upper Pleistocene coastal landscape associated with these caves is of paramount importance in the knowledge of human population subsistence. During the Upper Pleistocene, the ocean level changes drastically influenced the coastal geomorphology as well as the fauna assemblages. The chrono-lithostratographical analysis of the coastal sedimentary formations allows the distinction of three sequences rich in marine fauna. These sequences date from MIS 11 to MIS 5. The identification of malacofauna species from these deposits revealed 39 species, along with Bryozoans, Crustaceans, and Echinoids. These assemblages show a constant fauna cortege highlighted by the dominance of the amphi-Atlantic species Stramonita haemastoma. This species shows an increase in the number of specimens in the uppermost part of marine deposits, probably in relation with a climate warming in the MIS 5. This fauna of both intertidal rocky substrates and sandy substratum indicates environmental conditions close to the present-day Rabat-Témara coastline. As in other coastal locations of Africa from MIS 5, the Middle Stone Age Homo sapiens population benefitted from a littoral environment rich in coastal resources. Comparison between thanatocenoses and archaeological records allows us to identify both species available for Middle Stone Age population and those preferred for human use.  相似文献   
135.
136.
Australia, like most other developed democracies, is often alleged to suffer from ‘casualty phobia’. The perception that the Australian public will not tolerate casualties in foreign conflicts has shaped the decisions of both civilian and military policy makers. Measures taken to protect Australian forces from casualties may, for instance, also serve to increase the risk to civilians in the country to which they are deployed. The USA underwent a similar debate some years ago. Innovative public opinion research techniques—especially ‘survey experiments’ which allow researchers to establish causal relationships by consciously manipulating one variable while holding others constant—have established that the American public are not reflexively casualty-phobic and that the impact of casualties on public opinion can be outweighed by other factors, such as the public's confidence in the mission's overall success. In this article, the author replicates one of the key survey experiments from the US debate, suitably adapted to Australian conditions, with a nationally representative sample of Australian voters. The author finds that the same pattern holds in Australia as in the USA: casualties do lower public support for a given mission, but the mission's chances of success matter more.  相似文献   
137.
The Nasca culture of the south coast of Peru developed during the first millennium ad and is known internationally for its elaborately decorated polychrome pots. Despite decades of iconographic analysis, little is known about the more technological aspects of Nasca pigment production and application. We present results from a pilot study on iron isotopes as a potential line of inquiry into the differences between red and black pigments in Nasca pigments. As well, we conduct a small firing experiment to examine potential changes in isotope composition. Our analyses show three significant results. First, firing does not change the isotopic ratios of Fe in pigments. Second, red and black pigments show differences in their iron isotope composition, which relate to differences in the minerals used to make the different colors. Third, naturally available hematite samples show greater isotopic variation than pigment samples, suggesting that people selected a limited range of iron oxides to produce pigments.  相似文献   
138.
We locate Albert Lautman's work as a sort of agent of the break of symmetry in the framework of the traditional opposition of speculative philosophy and the physico-mathematical sciences. The stakes for philosophy are, with very rare exceptions, very poorly perceived. On this level, we return to the question of Lautman's supposed «Platonism» and we confront it with its fundamental reading of Martin Heidegger. The consequences of this insertion in the heideggerian furrow are fundamental for a just restitution of this thought and this philosophy into what they retain in current thought. On the other side, that of Lautmanian entries in the field of mathematical physics, we insist on the extreme prospective alacrity of his gaze, his philosophic power which comes to reinforce this strange sensibility toward what constituted the essential part of theoretical mathematics and physics in his time. In this sense, his position occupies actually one of the nodal points of the «surrationalistic» landscape.  相似文献   
139.
As the sobriquet «Zweistein» suggests, within the theoretical physics community Wolfgang Pauli came to be regarded as second in eminence only to Albert Einstein. Over a period of thirty-five years, they interacted both intellectually and personally. This paper focuses on four interrelated topics of their discussions. 1) The theory of relativity: at the age of twenty, Pauli prepared the definitive survey of relativity, a survey which he revised near the end of his life and which remains invaluable to physicists and historians of physics. 2) Unified field theories: although initially sympathetic to Einstein's search for a unified theory of electromagnetism and gravitation, and having made important contributions to the subject, Pauli came to regard such efforts as fruitless. 3) Foundations of quantum mechanics: Pauli's negative evaluation of Einstein's program grew out of their sharply differing evaluations of the role that quantum mechanics would play in the future, development of theoretical physics. 4) Quantum gravity: Pauli recognized that, until the achievement of a successful reconciliation of quantum mechanics and general relativity — an achievement that still eludes us — Einstein's challenge to quantum mechanics could not be laid to rest.  相似文献   
140.
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