Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
A detailed rock-magnetic and archeointensity study was carried out on materials baked by a western Mexican artisan following traditional techniques to produce faithful reproductions of archeological pieces of the Michoacan region (Western Mesoamerica). The field strength at the site (41.0 +/- 0.51 mu T) was measured with a fluxgate magnetometer and the temperature of the furnace during the baking process was monitored continually by means of a thermocouple placed in the middle of the baking cavity.;Rock-magnetic experiments performed on the raw material (clay and paste) and on in situ prepared baked ceramics and bricks included measurement of thermomagnetic curves (susceptibility and strong-field magnetization versus temperature), first-order reversal curves (FORC), anisotropy of magnetic susceptibility (AMS) and anisotropy of thermoremanent magnetization (A-TRM). Magnetite and probably hematite are present in the samples as carriers of the remanence. Hysteresis ratios suggest that the samples fall in the pseudo-single-domain grain size region, which may indicate a mixture of multidomain and a significant amount of single-domain grains.;Ceramic pieces and brick fragments were subjected to the Thellier-Coe archeointensity method and to an alternative paleointensity experiment, with a TRIAXE magnetometer, in order to check whether they are faithful recorders of the local geomagnetic field strength.;Mean raw-intensity of sample M1 (pottery) overestimates a 7% the expected site intensity, while those corresponding to the brick samples (LQ1 and LQ2) underestimate it 15%. Brick sample LNQ shows a slightly lower intensity (7%), but agrees with the expected site intensity within the experimental uncertainty. The intensity retrieved from the volcanic fragment also included closely reproduces the expected intensity. After A-TRM and cooling-rate corrections, all mean raw values move closer to the expected intensity.;Measurement of temperatures at different parts inside the kiln (bottom and upper parts of both central and peripheral parts) revealed the existence of significant thermal gradients, similar to those observed in ovens from other localities. Different cooling rates are then expected in a single oven.;The scatter in the intensity determinations observed in this study, retrieved from pieces elaborated together in the same oven, could arise from this differentiated cooling rate within the oven and thus, to an inappropriate cooling rate correction in the archeointensity protocol. As this situation was probably reproduced in the baking of ancient ceramic artifacts, a better knowledge of the temperature distribution inside these types of kiln would be desirable in order to choose the appropriate cooling rate correction.
ISSN: 0031-9201

hal-00644559
https://hal.archives-ouvertes.fr/hal-00644559
DOI : 10.1016/j.pepi.2011.06.007

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Sphingolipids, in particular ceramide, have been described as important components of cellular signalling pathways. Ceramide can be produced via multiple mechanisms including through the hydrolysis of sphingomyelin by acid and neutral sphingomyelinase or by a de novo synthesis pathway. Recent studies have identified sphingomyelinases and ceramide synthases as important targets for γ-irradiation and chemotherapeutic drugs. Likewise, common cancer treatment modalities, such as γ-irradiation and many chemotherapeutic agents, induce cell death via the generation of ceramide. This suggests that the manipulation of ceramide production and metabolism could offer promising a means for the enhancement of anti-tumor therapies. The focus of this mini-review will be to discuss contemporary evidence suggesting that ceramide forming pathways and ceramide itself are important targets for the treatment of tumors and the development of novel tumor treatment strategies.
ISSN: 0304-3835

hal-00682458
https://hal.archives-ouvertes.fr/hal-00682458
DOI : 10.1016/j.canlet.2011.07.010
PUBMED : 21862212

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Numerous archeomagnetic studies have provided high quality data for both the direction and the intensity of the geomagnetic field, essentially in Europe for the last 10 millennia. In particular, Greece supplies a lot of archeological materials due to its impressive cultural heritage and volcanic activity, so that numerous data have been obtained from burnt clays or historical lava flows. The most recent Greek secular variation curves are available for the last 8 millennia for the intensity and the last 6 millennia for the direction. Nevertheless, the coverage still presents several gaps for periods older than 2500 BC. In an effort to complete the Greek curve and extend it to older times, we present the archeointensity results from three Neolithic settlements in Northern Greece. The samples are of two different natures: burnt structures from Avgi (5250 ± 150 BC) and Vasili (4800 ± 200 BC), as well as ceramics from Dikili Tash (4830 ± 80 BC) and Vasili (4750 ± 250 BC). The samples have been subjected to standard rock magnetic analyses in order to estimate the thermal stability and the domain state of the magnetic carriers before archeointensity measurements. Surprisingly, very few ceramic samples provided reliable archeointensities whereas samples from burnt structures presented a very good success rate. Complementary studies showed that a detailed examination of the matrix color, following archeological information and classification standards can be a decisive test for pre-selection of sherds. In spite of these unsuccessful measurements from ceramics, we obtained an intensity value of 73.5 ± 1.1 μT for Dikili Tash, a higher value than the other data obtained in the same area, during the same period. However we do not have evidences for a technical artefact during the experiment. The burnt structures yielded two reliable archeointensities of 36.1 ± 1.8 μT and 46.6 ± 3.4 μT for Avgi and Vasili, respectively. Finally, we achieved a new archeomagnetic dating for these sites by comparing these new archeointensity values, combined to the directional measurements already published, with the Bulgarian secular variation curve. These new results contribute to extend the Greek secular variation reference curve towards older periods.
ISSN: 0031-9201

hal-00805575
https://hal.archives-ouvertes.fr/hal-00805575
DOI : 10.1016/j.pepi.2012.10.011

Éditeur(s) : HAL CCSD Sidestone Press
Résumé : International audience
In 2006, an INRAP team led by T. Romon proceeded to search the Amerindian dump of the Gare Maritime in Basse-Terre. An important collection of ceramics there was discovered and then examined by Mr. Hildebrand. The results made possible to assign the occupation to subseries of old huecan and Cedrosan Saladoid.As part of a master’s degree research in archaeology, a study of sets of this pottery was considered a new approach. The latter, inspired by an analysis ofJ. Van Berg on the Rubanné ceramics, can be called structural. Indeed, the search for elementary motifs in this type of decoration, said abstract, can reconstruct it by studying how the motifs fit together. We can compare the motifs to a panel of vocabulary, which combine according to rules of "grammar" defined.This method thus relies on a precise statistical analysis that highlights thecombinatorial rules by inserting an additional factor: that of the various decorating techniques (etching, engraving, painting, modeling).These rules can be translated simply by notions of "presence / absence" or by incorporating a notion of frequency depending on the level of complexity of the decoration. This is the number of motifs creating the set. We call this the set of one or two motifs for simple associations or of four or five motifs for complex sets.The objective of this study is to express an early hypothesis, which would tend to reveal the existence or not of a specific hierarchy of elementary motifs depending on various factors such as complexity of the set or the technique used in both huecan and Cedrosan subseries.
En 2006, un equipo del INRAP dirigido por T. Romon procedió a la excavación del vertedero amerindio de la Estación Marítima en Bsse-terre. Una importante colección de cerámica fue puesta allí al día y a continuación estudiada por el Sr. Hildebrand. Los resultados obtenidos permitieron de asignar esta ocupación a las subseries del Saladoïde huecan y cedrosan antiguos.En el marco de un curso de posgrado en arqueologia, se previo un estudio de los decorados de este conjunto de cerámica según un nuevo enfoque. Esta última, inspirada en un análisis realizado por J. Van Berg, en la cerámica Rubannée,se puede llamar estructural. En efecto, la búsqueda de los motivos elementales en este tipo de decorado, dicho abstracto, permiten reconstruirlo estudiando la forma en que los motivos se arreglan. Podemos comparar los motivos a un cuadro de vocabulario que se combina según normas “gramaticales” definidas.Este método se basa, pues en un análisis de estadística precisa que pone de relieve las reglas combinatorias mediante la inserción de un factor adicional: la delas diferentes técnicas de decoración (aguafuerte, grabado, pintura, modelado).Estas normas pueden traducirse simplemente en conceptos de “presencia/ausencia” o incorporando un concepto de frecuencia según el nivel de complejidad del decorado. Este último corresponde entre motivos que crean el decorado. Hablamos entonces de decorado a unos o dos motivos para las asociaciones simples o a cuatro o cinco motivos para los decorados complejos.El objetivo de este estudio es de emitir un principio de hipótesis que tendería a revelar la existencia, o no, de una jerarquía específica de los motivos elementales en función de los distintos factores, como la complejidad del decorado o la técnica utilizada, en las dos subseries huecan y cedrosan
En 2006, une équipe de l'INRAP dirigée par T. Romon procéda à la fouille du dépotoir amérindien de la Gare Maritime à Basse-Terre. Une importante collection de céramique y fut mise au jour et ensuite étudiée par M. Hildebrand. Les résultats obtenus permirent d'attribuer cette occupation aux sous-séries du Saladoïde huecan et cedrosan ancien. Dans le cadre d'un master en archéologie, une étude des décors de cet ensemble céramique fut envisagée selon une nouvelle approche. Cette dernière, inspirée d'une analyse effectuée par J. Van Berg sur la céramique du Rubané, peut être qualifiée de structurale. En effet, la recherche des motifs élémentaires dans ce type de décor, dit abstrait, permet de le reconstruire en étudiant la façon dont les motifs s'agencent. Nous pouvons comparer les motifs à un panel de vocabulaire qui se combine selon des règles « grammaticales » définies.Cette méthode s'appuie ainsi sur une analyse statistique précise qui met en exergue les règles combinatoires en insérant un facteur supplémentaire : celui des différentes techniques de décoration (gravure, incision, peinture, modelage). Ces règles peuvent se traduire simplement par des notions de « présence / absence » ou bien en incorporant une notion de fréquence selon le niveau de complexité du décor. Ce dernier correspond au nombre de motifs créant le décor. Nous parlons alors de décor à un ou deux motifs pour les associations simples ou bien à quatre ou cinq motifs pour les décors complexes. L'objectif de cette étude est d'émettre un début d’hypothèse qui tendrait à révéler l'existence, ou non, d'une hiérarchie spécifique des motifs élémentaires en fonction des différents facteurs, comme la complexité du décor ou la technique utilisée, chez les deux sous-séries huecanes et cedrosanes.
Archéologie Caraïbe

Droits : info:eu-repo/semantics/OpenAccess
ISBN : 978-90-8890-291-8
halshs-01140826
https://halshs.archives-ouvertes.fr/halshs-01140826
https://halshs.archives-ouvertes.fr/halshs-01140826/document
https://halshs.archives-ouvertes.fr/halshs-01140826/file/Honore%20%26%20Berard%202014%20-%20Etude%20analytique%20des%20decors%20ceramiques%20du%20site%20de%20la%20Gare%20Maritime.pdf

Éditeur(s) : HAL CCSD Archaeopress
Résumé : International audience
The first formative occupation of the West Indies was by continental populations, moving up from their place of origin in the Orinoco Basin, shortly before our era. In Martinique these groups, attached to the cedrosan saladoid sub-series, have been well studied and for a considerable time. It is upon this work that we have attempted to build an overall analysis of this phase of the prehistory of the Islands. The research drew upon the results of unpublished field work. This led to a more precise understanding of the nature and constitution of these archeological strata and, in turn, of the organisation of the Amerindian villages and their management of the island space. A review of their artisanal production ( ceramics, stone tools, personal adornment) has given us a closer understanding of these populations. It also provides the basis for a future paleo-ethnographic study. Further, an analysis of the origin of the lithic materials has enabled us to place the ancient saladoid occupation of Martinique both in the geography of the West Indian Arc and in the Carribean Basin as a whole. Progressively a picture was thus put together of pioneer agro-ceramicist groups characterised by a high degree of organisation and by the spiritual concepts expressed in their artisanal production.
Les premières occupations formatives des Antilles sont liées à la migration, peu avant le début de notre ère, de populations continentales originaires du bassin de l'Orénoque. En Martinique, l'étude de ces groupes, rattachés à la sous-série saladoïde cedrosane, a une histoire riche et ancienne. C'est fort de ces acquis que nous avons tenté de réaliser une analyse globale de cette phase de la préhistoire des Antilles. Notre recherche s'appuie sur l'analyse des résultats d'un ensemble d'opérations de terrain inédites. Les informations ainsi obtenues nous permettent d'étudier la nature et le mode de constitution de ces gisements archéologiques. On commence alors à distinguer l'organisation de ces villages amérindiens et le mode de gestion de l'espace insulaire qui s'y rattache. L'analyse de différents types de productions artisanales (céramique, outillage en pierre, parure) nous permet d'accéder à une connaissance plus intime de ces populations. Elle offre aussi les moyens nécessaires à la réalisation d'une future étude palethnographique. Par ailleurs, l'analyse de l'origine géographique des matières premières lithiques nous permet de réintégrer l'occupation saladoïde ancienne de la Martinique dans l'espace géographique qui est le sien!: l'arc antillais et plus largement le bassin caraïbe. Ainsi, se dégage progressivement l'image de groupes pionniers agro-céramistes caractérisés par un très haut degré d'organisation et par la matérialisation permanente de leurs conceptions spirituelles au travers de leur production artisanale.
https://hal.univ-antilles.fr/hal-00966882

ISBN : 1 84171 649 9
hal-00966882
https://hal.univ-antilles.fr/hal-00966882

Éditeur(s) : HAL CCSD Nature Publishing Group
Résumé : International audience
Epithelial-to-mesenchymal transition (EMT) promotes cell motility, which is important for the metastasis of malignant cells, and blocks CD95-mediated apoptotic signaling triggered by immune cells and chemotherapeutic regimens. CD95L, the cognate ligand of CD95, can be cleaved by metalloproteases and released as a soluble molecule (cl-CD95L). Unlike transmembrane CD95L, cl-CD95L does not induce apoptosis but triggers cell motility. Electron paramagnetic resonance was used to show that EMT and cl-CD95L treatment both led to augmentation of plasma membrane fluidity that was instrumental in inducing cell migration. Compaction of the plasma membrane is modulated, among other factors, by the ratio of certain lipids such as sphingolipids in the membrane. An integrative analysis of gene expression in NCI tumor cell lines revealed that expression of ceramide synthase-6 (CerS6) decreased during EMT. Furthermore, pharmacological and genetic approaches established that modulation of CerS6 expression/activity in cancer cells altered the level of C16-ceramide, which in turn influenced plasma membrane fluidity and cell motility. Therefore, this study identifies CerS6 as a novel EMT-regulated gene that has a pivotal role in the regulation of cell migration.Oncogene advance online publication, 17 March 2014; doi:10.1038/onc.2014.55.
ISSN: 0950-9232

hal-01063558
https://hal.archives-ouvertes.fr/hal-01063558
https://hal.archives-ouvertes.fr/hal-01063558/file/Down-regulation%20of%20ceramide_accepted.pdf
DOI : 10.1038/onc.2014.55
PUBMED : 24632610

Éditeur(s) : HAL CCSD Oxford University Press
Résumé : International audience
Pre-Columbian sites with similar artifacts were excavated at an early date in Trinidad (Howard 1943) and the West Indies (Rouse 1940), but the classification of these sites as reflecting a common culture area was not achieved until Cruxent and Rouse (1958/1959) defined the Saladoid "series" (i.e., related "peoples and cultures") following research in the Orinoco River valley of Venezuela. This name became widely adopted following the first international convention for the study of the pre-Columbian cultures of the Lesser Antilles in 1961, and it quickly replaced the appellation "Arawak" to designate the first Antillean ceramic groups. The Saladoid series culture area includes the Orinoco River basin, parts of the north coast of South America, and the Lesser Antilles and Puerto Rico. This chapter present the state of art about Saladoid series.
The Oxford Handbook of Caribbean Archaeology

Droits : info:eu-repo/semantics/OpenAccess
ISBN : 978-0-19-539230-2
hal-00968898
https://hal.univ-antilles.fr/hal-00968898
https://hal.univ-antilles.fr/hal-00968898/document
https://hal.univ-antilles.fr/hal-00968898/file/Chap13saladoid.pdf

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
Fish mucus has important biological and ecologicalroles such as defense against fish pathogens andchemical mediation among several species. A non-targetedliquid chromatography–mass spectrometry metabolomicapproach was developed to study gill mucus of eight butterflyfishspecies in Moorea (French Polynesia), and theinfluence of several fish traits (geographic site and reefhabitat, species taxonomy, phylogeny, diet and parasitismlevels) on the metabolic variability was investigated. Abiphasic extraction yielding two fractions (polar and apolar)was used. Fish diet (obligate corallivorous, facultativecorallivorous or omnivorous) arose as the main driver ofthe metabolic differences in the gill mucus in both fractions,accounting for 23% of the observed metabolic variabilityin the apolar fraction and 13% in the polar fraction.A partial least squares discriminant analysis allowed us toidentify the metabolites (variable important in projection,VIP) driving the differences between fish with differentdiets (obligate corallivores, facultative corallivores andomnivorous). Using accurate mass data and fragmentationdata, we identified some of these VIP as glycerophosphocholines,ceramides and fatty acids. Level of monogeneangill parasites was the second most important factor shapingthe gill mucus metabolome, and it explained 10% of themetabolic variability in the polar fraction and 5% in theapolar fraction. A multiple regression tree revealed that themetabolic variability due to parasitism in the polar fractionwas mainly due to differences between non-parasitized andparasitized fish. Phylogeny and butterflyfish species werefactors contributing significantly to the metabolic variabilityof the apolar fraction (10 and 3%, respectively) buthad a less pronounced effect in the polar fraction. Finally,geographic site and reef habitat of butterflyfish species didnot influence the gill mucus metabolome of butterflyfishes.
ISSN: 0722-4028

hal-01563312
https://hal-univ-perp.archives-ouvertes.fr/hal-01563312
DOI : 10.1007/s00338-017-1554-0

Éditeur(s) : HAL CCSD Société des amis du Musée national de préhistoire et de la recherche archéologique — SAMRA
Résumé : International audience
Lithic technology studies have been late developed in the Antilles. The first important works about the knapping technology of the first agro-ceramist cultures (saladoid) have shown the use of the bipolar technique. A new research program based on the analysis of cedrosan and huecan saladoid lithic collections from Martinique and Guadeloupe, gave us the possibility to confirm and refine those first data. The technological analysis, associated to an experimentation program defined to help us to characterize the striking techniques used, have shown a systematic use of the bipolar technique for the débitage of good quality raw materials. The chaînes opératoires of reduction are highly efficient producing a set of small flakes. The morphology of those flakes, linked to the use of the bipolar technique, is perfectly adapted to their use as manioc grater teeth.
L'étude des restes de débitage a connu un développement tardif dans les Antilles. Les premiers travaux importants sur les débitages des premières cultures formatives (saladoïde) ont mis en évidence l'utilisation de la percussion posée sur enclume. Le développement d'un programme de recherche sur les séries lithiques saladoïdes cedrosanes et huecanes de Martinique et de Guadeloupe nous a permis de confirmer et d'affiner ces premières observations. L'analyse technologique, complétée par un programme expérimental destiné à éclaircir la question des techniques de percussion, a montré l'existence d'une utilisation systématique de la percussion posée sur enclume pour l'exploitation de matières premières de bonne qualité. Les chaînes opératoires de débitage sont d'une grande efficacité et permettent très rapidement d'obtenir des séries de petits éclats faiblement standardisés. Les caractéristiques morphologiques de ces éclats, étroitement liées à la technique de percussion employée, en font des supports parfaitement adaptés à une utilisation comme dents de râpes à manioc.
ISSN: 1145-3370

hal-00974212
https://hal.univ-antilles.fr/hal-00974212

Éditeur(s) : HAL CCSD Springer Verlag (Germany) Springer Verlag
Résumé : Dihydroceramide ?4-desaturase 1 (DES1) catalyzes the last step of the de novo ceramide biosynthesis, which consists of the introduction of a trans ?4-double bond in the carbon chain of the dihydroceramide. It was previously observed that myristic acid binds DES1 through N-myristoylation. This N-terminal modification significantly increased the activity of the recombinant DES1 in COS-7 cells and targeted part of the enzyme initially present in the endoplasmic reticulum to the mitochondrial outer membrane, leading to an increase in ceramide levels. Since these results were obtained in a recombinant COS-7 cell model with high expression of rat DES1, the purpose of the present study was to investigate if the native DES1 enzyme was really upregulated by its N-myristoylation in cultured rat hepatocytes. We first showed that DES1 was the main dihydroceramide desaturase isoform expressed in rat hepatocytes. In this model, the wild-type myristoylable recombinant form of rat DES1 was found in both the endoplasmic reticulum and the mitochondria whereas the mutated non-myristoylable recombinant form (N-terminal glycine replaced by an alanine) was almost exclusively localized in the endoplasmic reticulum, which evidenced the importance of the myristoylation. Then, we showed that compared to other fatty acids, myristic acid was the only one to increase native DES1 activity, in both total cell lysates and mitochondrial fractions. The myristic acid-associated increase in DES1 activity was not linked to elevated mRNA or protein expression but more likely to its N-terminal myristoylation. Finally, the myristic acid-associated increase in DES1 activity slightly enhanced the number of apoptotic cells.
ISSN: 0024-4201

hal-00808026
https://hal-agrocampus-ouest.archives-ouvertes.fr/hal-00808026
DOI : 10.1007/s11745-011-3638-x

Éditeur(s) : HAL CCSD
Résumé : International audience
After an important methodological presentation of lithic technology analysis, we present in this paper a diachronical study of the martinican Amerindian flint-knapping technology. This work completes the results of ceramics analysis and open new ways of understanding of the prehistorical cultural changes.
L'analyse technologique des industries lithiques a pour objectif la caractérisation des méthodes et des techniques de taille. Elle s'appuie sur la conception de l'acte technique comme un fait culturel à part entière. L'analyse d'un système technique permet alors la caractérisation d'un ensemble culturel et par là même la comparaison de différents ensembles. L'analyse technologique du débitage en particulier s'appuie sur la lecture et l'interprétation des différents stigmates liés à la fracture conchoïdale. Ces stigmates permettent de déterminer, la nature, la direction et la chronologie des enlèvements, et ainsi de réintégrer chaque pièce au sein d'une chaîne opératoire de débitage. C'est ce type d'étude que nous avons conduite en Martinique. Nous avons ainsi pu revoir, à la lumière de l'évolution des méthodes de débitage, la séquence culturelle de cette île. Nous pouvons ainsi mieux appréhender l'importance des changements, mis en évidence par l'étude de la céramique, par la prise en compte d'autres éléments du système technique.
Actes du XVIIIéme congrès de l'Association Internationale d'Archéologie de la Caraïbe, St. George, Grenade 1999
Saint George, Grenada

hal-00966338
https://hal.univ-antilles.fr/hal-00966338
https://hal.univ-antilles.fr/hal-00966338/document
https://hal.univ-antilles.fr/hal-00966338/file/Technologie_lithique_et_caractA_risation_culturelle.pdf