Search results for "ley"

Hirnantian glacial and deglacial record in SW Djado Basin (NE Niger).

2007

Pluridisciplinary fieldwork highlights features generated by an extended ice-sheet in the Djado Basin during the Hirnantian. Two glacial palaeovalley systems associated with glacial pavements and separated by thin glaciomarine interstadial series are revealed. Rigid glacial pavements characterised by abrasion erosion are differentiated from soft glacial pavements characterised by soft-bed deformation. Glacial pavements are associated with subglacial bedforms such as megaflutes, flutes and meltwater channels. They are also associated with clastic dykes and glaciotectonic structures such as deformed flutes, subglacial folds and duplex structures. This record demonstrates that ice was warm-bas…

Abnormal peripubertal development of the rat mammary gland following exposure in utero and during lactation to a mixture of genistein and the food co…

2011

The impact of early exposure to endocrine disruptor mixtures on mammary gland development is poorly known. Here, we identify the effects of a conception to weaning exposure of rats to the phytoestrogen genistein (G) and/or the antiandrogen vinclozolin (V) at 1 mg/kg-d, alone or in association. Using several approaches, we found that G- and GV-exposed rats displayed significantly greater epithelial branching and proliferation, wider terminal end buds than controls at PND35, as well as ductal hyperplasia and periductal fibrosis. Focal branching defects were present in V-exposed rats. An increased ER and AR expression was observed in G- and CV- as compared to V-exposed rats at PND35. Surprisin…

Ventilatory conditioning by self-stimulation in rats: A pilot study

1994

International audience; This article describes an experimental attempt to condition breathing pattern in rats. In this experiment, a freely moving rat was first rewarded by an electrical stimulation of the medial forebrain bundle whenever inspiratory duration (TI) exceeded 300 ms. A bidirectional control was then used: TIs longer than 400 ms were rewarded, and then TIs shorter than 300 ms were rewarded. The frequency of TIs longer than 300 ms increased when this event was rewarded, further increased when TIs above 400 ms were rewarded, and decreased during reversal conditioning (TI < 300 ms). At the beginning of the experiment, stimulation caused increased arousal and motor activity, but af…

Evolution and management of humid landscapes in Northern Dauphiné (Rhône valley, France): contribution of charcoal and wood studies

2011

International audience; Evolution and management of humid landscapes in Northern Dauphiné (Rhône valley, France): contribution of charcoal and wood studies

Relationships between societies and their environment in the Sahel in southwestern Niger over the past four thousand years : a geoarchaeological appr…

2013

The Sahel, a zone between the Sahara Desert and the Sudan forests, is currently experiencing major environmental changes. Since the droughts in 1970s and 1980s, and with the high population growth rate, vegetation cover has deteriorated considerably, contributing to increased runoff and soil erosion. Starting from this observation, we undertook the study of past societies in the Niamey region, to assess their impact on the environment. The lack of archaeological data meant that it was necessary to identify key indicators of occupation during the Neolithic and the Iron Age. In addition to providing new evidence to date the Neolithic site of Kirkissoy, a sedimentary study was conducted on a p…

Observations of land use transformations during the Neolithic using exploratory spatial data analysis: contributions and limitations

2010

International audience; The settlement pattern analysis in archaeology implies some methodological questions. In this paper, we question some issues about the use of geostatistical methods for the observation of land use transformations during the Neolithic. We have developed two examples in Burgundy (France): the first one on a regional scale and the second one on a micro-regional scale. Using different ESDA approaches (Ripley’K function, Nearest Neighbour Distance, Kernel Density Estimation), we would like to underline what the methodological and archaeological contributions and their limits are. Both experiences point out that the results obtained depend not only on the analytical scale,…

Technologies de fibules du Mont-Beuvray

1988

Notes P.H. Blyth. Métallurgie des armes de bronze (pl. VI à IX) M. Pernot, J. Dubos et J.-P. Guillaumet. Technologies de fibules du Moht-Beuvray

Découverte d'un pied antique en forme de sphinge, à proximité de Chalon-sur-Saône (Saône-et-Loire)

2010

A figurative element made out of bronze was discovered in a 2008 evaluation at Fragnes (Saône-et-Loire) near to Chalon-sur-Saône. This very original element was discovered in an untypical context. It is the foot of a vessel in the form of a sphinx with a lion's paw. Even though objects with decorated feet and in particular lion's paws are well known of, the use of the sphinx iconography is rare and even unique in Gaul during this period

Food production and diet during the Late Bronze Age in upper Seine valley (France)

2015

Les minières de silex néolithiques des marais de Saint-Gond (Marne)

2014

In the southern and eastern area of the Côte d’Île-de-France, north of the marshes of Saint-Gond (Marne, France), research incorporating a great deal of unpublished documentation, and the results of pedestrian and aerial surveys, has highlighted five flint mines. For various reasons, the many indications of mining activity in this region have never been considered sufficient to consider it a mining area, however, the combination of a series of objective observations suggests the existence of five flint mines.In several sites, flint mining was conducted from shafts several metres deep, sometimes connected by galleries. As many archaeological discoveries made during the earlier excavations ha…