Archaeological Investigations between Cayenne Island and the Maroni River

Stratigraphic archaeological research in French Guiana is barely 50 years old and has been conducted primarily in the coastal zone, stretching approximately between 5 and 50 kilometres from the Atlantic coast to the Precambrian Shield. This bias, mainly caused by means of modern infrastructure, has sketched an archaeological record concerning pre-Columbian French Guiana focussing on the Late Ceramic Age (AD 900-1500) of Cayenne Island as well as the western Holocene coastal plains. The present study contains the results of six archaeological investigations, conducted from a compliance archaeological perspective, in order to enhance our knowledge of the afore-mentioned coastal area. It not only presents us with fresh archaeological data on the (Late) Archaic and Early Ceramic Age, a hiatus that is now partially filled up, but also sheds new light on the Late Ceramic Age of this specific region concerning funerary rites, ceramic series and subsistence economy. Martijn van den Bel studied History and Archaeology of Indigenous America at Leiden University and graduated in 1995 with an ethnoarchaeological study on the Palikur potters of French Guiana. Currently he works as a project leader for Inrap in French Guiana. He carries out compliance archaeological research in the French Guiana and the French Lesser Antilles. Next to archaeology, Martijn is interested in the early history of the Guianas and the Lesser Antilles, notably the encounter between Amerindians and Europeans during the 16th and 17th century, resulting in various publications

Nouveaux apports sur l’archéologie du littoral de Guyane : de la préhistoire à la conquête

En Guyane française, les recherches archéologiques structurées ne datent que du début des années 1970. Elles furent synthétisées par Stéphen Rostain au début des années 1990. Le cadre chrono-culturel établi alors se concentrait surtout sur la bande littorale entre les rivières de Kourou et de l’Oyapock et sur la période entre 900 et 1700 de notre ère. Cette étude résume les résultats de six fouilles archéologiques préventives plus récentes. Celles-ci permettent d’abord d’étoffer le cadre chrono-culturel de la préhistoire de ce département français. En effet des données nouvelles élargissent substantiellement ce cadre sur l’Âge archaïque et sur la période céramique ancienne, deux époques inconnues jusque-là. De nouveaux éléments renouvellent aussi certaines perspectives de la période céramique récente, en particulier sur les pratiques funéraires, les complexes céramiques et l’alimentation des Amérindiens.In French Guiana, structured archaeological research only started in the early 1970s. Its results have been synthesized by Stéphen Rostain twenty year later. The proposed chronocultural framework focused mainly on the coastal plains situated between the Oyapock and Kourou Rivers for the Late Ceramic Age, between AD 900 and 1700. This study presents the condensed results of six recent compliance archaeological excavations. They permit us firstly to enrich the existing framework of this overseas French department by presenting new data concerning the Archaic and Early Ceramic Ages, hitherto undiscovered episodes, substantially enlarging this framework. Furthermore, new elements concerning the Late Ceramic Age renew certain aspects, notably concerning funerary practices, ceramic complexes and food consumption of the prehistoric Amerindians.Na Guiana Francesa, pesquisas arqueológicas estruturadas só começaram no início da década de 1970 e seus resultados foram sintetizados por Stéphen Rostain no início dos anos 1990. O quadro cronocultural proposto focava principalmente nas planícies costeiras situadas entre os rios Oiapoque e Kourou para o Período Cerâmico tardio, entre 900 e 1700 AD. Este estudo apresenta os resultados condensados de seis escavações de arqueologia preventiva. Eles nos permitem, primeiramente, enriquecer o quadro existente deste departamento ultramarino francês; além disso, são apresentados aqui novos dados sobre os Períodos Cerâmicos arcaico e inicial, episódios até então não descobertos, ampliando substancialmente esse panorama. Finalmente, novos elementos relativos ao Período Cerâmico tardio renovam certos aspectos, notadamente, sobre práticas funerárias, complexos cerâmicos e consumo de alimentos das populações ameríndias pré-históricas

Archaeological investigations between Cayenne Island and the Maroni river : a cultural sequence of western coastal Franche Guiana from 5000 BP to present

2 septembre 2015 Université de Leyde  Membres du Jury Directeurs de thèseCorinne L. Hofman, Professeure, université de LeydeArie Boomert, Chercheur, université de LeydeRapporteurs Maarten E.R.G.N. Jansenn, Professeur, université de LeydeEduardo Góes Neves, Professeur, Musée d’archéologie et d’ethnologie de l’université de São PauloEithne B. Carlin, Chercheuse, université de LeydeExaminateurs Humphrey H. H. Kanhai, Professeur, université de LeydeDavid R. Fontijn, Professeur, université de Leyd..

The Tapuia of Northeastern Brazil in Dutch sources (1628–1648)

This book presents the transcriptions and annotated translations of fifteen key historical documents concerning the Tapuia indigenous people written just before and during the Dutch occupation of northeastern Brazil. The selected documents vary widely in type, including letters, descriptions, reports, first-person declarations, diaries, and transcripts of interrogations, thereby showcasing different perspectives and audiences. Some of the documents were authored by European writers, while others register indigenous voices somewhat more directly in the form of interviews or declarations.These texts provide important first-hand information about the Tapuia and other indigenous peoples during the Dutch conquest, revealing their cultural practices and knowledge while also detailing their strategic engagements with each other and with different European colonizers.Horizon 2020(H2020)ERC Agreement No. 715423Heritage of Indigenous People

Complete classification of purely magnetic, non-rotating and non-accelerating perfect fluids

Recently the class of purely magnetic non-rotating dust spacetimes has been shown to be empty (Wylleman, Class. Quant. Grav. 23, 2727). It turns out that purely magnetic rotating dust models are subject to severe integrability conditions as well. One of the consequences of the present paper is that also rotating dust cannot be purely magnetic when it is of Petrov type D or when it has a vanishing spatial gradient of the energy density. For purely magnetic and non-rotating perfect fluids on the other hand, which have been fully classified earlier for Petrov type D (Lozanovski, Class. Quant. Grav. 19, 6377), the fluid is shown to be non-accelerating if and only if the spatial density gradient vanishes. Under these conditions, a new and algebraically general solution is found, which is unique up to a constant rescaling, which is spatially homogeneous of Bianchi type $VI_0$, has degenerate shear and is of Petrov type I($M^\infty)$ in the extended Arianrhod-McIntosh classification. The metric and the equation of state are explicitly constructed and properties of the model are briefly discussed. We finally situate it within the class of normal geodesic flows with degenerate shear tensor.Comment: 12 pages; introduction partly rewritten, notation made more clear, table of results adde

Energetics of the Einstein-Rosen spacetime

A study covering some aspects of the Einstein--Rosen metric is presented. The electric and magnetic parts of the Weyl tensor are calculated. It is shown that there are no purely magnetic E--R spacetimes, and also that a purely electric E--R spacetime is necessarily static. The geodesics equations are found and circular ones are analyzed in detail. The super--Poynting and the ``Lagrangian'' Poynting vectors are calculated and their expressions are found for two specific examples. It is shown that for a pulse--type solution, both expressions describe an inward radially directed flow of energy, far behind the wave front. The physical significance of such an effect is discussed.Comment: 19 pages Latex.References added and updated.To appear in Int.J.Theor.Phy

Frame dragging, vorticity and electromagnetic fields in axially symmetric stationary spacetimes

We present a general study about the relation between the vorticity tensor and the Poynting vector of the electromagnetic field for axially symmetric stationary electrovacuum metrics. The obtained expressions allow to understand the role of the Poynting vector in the dragging of inertial frames. The particular case of the rotating massive charged magnetic dipole is analyzed in detail. In addition, the electric and magnetic parts of the Weyl tensor are calculated and the link between the later and the vorticity is established. Then we show that, in the vacuum case, the necessary and sufficient condition for the vanishing of the magnetic part is that the spacetime be static.Comment: 16 pages Latex. Some minor changes in the text and typos correcte

Diaphragm and abdominal organ motion during radiotherapy:a comprehensive multicenter study in 189 children

Background: For accurate thoracic and abdominal radiotherapy, inter- and intrafractional geometrical uncertainties need to be considered to enable accurate margin sizes. We aim to quantify interfractional diaphragm and abdominal organ position variations, and intrafractional diaphragm motion in a large multicenter cohort of pediatric cancer patients (&lt; 18 years). We investigated the correlation of interfractional position variations and intrafractional motion with age, and with general anesthesia (GA). Methods: In 189 children (mean age 8.1; range 0.4–17.9 years) from six institutes, interfractional position variation of both hemidiaphragms, spleen, liver, left and right kidneys was quantified using a two-step registration. CBCTs were registered to the reference CT relative to the bony anatomy, followed by organ registration. We calculated the group mean, systematic and random errors (standard deviations Σ and σ, respectively) in cranial-caudal (CC), left-right and anterior-posterior directions. Intrafractional right hemidiaphragm motion was quantified using CBCTs on which the breathing amplitude, defined as the difference between end-inspiration and end-expiration peaks, was assessed (N = 79). We investigated correlations with age (Spearman’s ρ), and differences in motion between patients treated with and without GA (N = 75; all &lt; 5.5 years). Results: Interfractional group means were largest in CC direction and varied widely between patients, with largest variations in the right hemidiaphragm (range -13.0–17.5 mm). Interfractional group mean of the left kidney showed a borderline significant correlation with age (p = 0.047; ρ = 0.17). Intrafractional right hemidiaphragm motion in patients ≥ 5.5 years (mean 10.3 mm) was significantly larger compared to patients &lt; 5.5 years treated without GA (mean 8.3 mm) (p = 0.02), with smaller Σ and σ values. We found a significant correlation between breathing amplitude and age (p &lt; 0.001; ρ = 0.43). Interfractional right hemidiaphragm position variations were significantly smaller in patients &lt; 5.5 years treated with GA than without GA (p = 0.004), but intrafractional motion showed no significant difference. Conclusion: In this large multicenter cohort of children undergoing thoracic and abdominal radiotherapy, we found that interfractional position variation does not depend on age, but the use of GA in patients &lt; 5.5 years showed smaller systematic and random errors. Furthermore, our results showed that breathing amplitude increases with age. Moreover, variations between patients advocate the need for a patient-specific margin approach.</p