CONTRIBUTION DE LA NANOTECHNOLOGIE ET LA NANOSCIENCE A L’EMERGENCE D’UN NOUVEAU TYPE DE CENTRALITE APPELE : LA NANOCENTRALITE NUMERIQUE ET INTELLIGENTE

ABSTRACTOver the last two decades, urban-urban architects have noticed nanotechnology and nanoscience-induced changes in the functioning and layout of human settlements and their contemporary urban centralities. The aim of this article is to explain the changes brought about by the two recent specialties on contemporary urban centrality. It is the era of a new form of centrality called: Digital and intelligent nanocentrality composed of digitized and high intelligence equipment, meets the requirements of the new digital revolution, that took on a new impetus at the beginning of this twenty-first century in the majority disciplines. These nanocentralities are connected by virtual networks in the form of a "spider web" via last generation satellites. These nanocentralities will manage various problems, including, the supremacy of the urban on the territories and what it has generated as spreading and fragmentation, become unavoidable in most urban situations.Au cours des deux dernières décennies, les architectes –urbanistes ont noté des changements induits par la nano technologie et la nanoscience sur le fonctionnement et l’aménagement des établissements humains et leurs centralités urbaines contemporaines. Delà, l’objectif de cet article, est de participer à l’explicitation des mutations apportées par les deux récentes spécialités sur la centralité urbaine contemporaine. C’est l’ère d’une nouvelle forme de centralité que nous avons appelé : Nanocentralité numérique et intelligente composée d’équipements numérisés et de haute intelligence et qui répond aux exigences de la nouvelle révolution numérique et digitale qui a pris un nouvel élan au début de ce vingt et un nième siècle dans la majorité des disciplines. Ces nanocentralités sont reliées par des réseaux virtuels sous forme d’une « toile d’araignée » via des satellites dernière génération et elles vont gérer des problématiques diverses dont, la suprématie de l’urbain sur les territoires et ce qu’il a engendré comme étalement et fragmentation, devenus incontournable dans la plus part des situations urbaines.MOTS CLES: Centralité urbaine contemporaine, nanotechnologie et nanoscience, nano centralité numérique et intelligente, polynanocentralité numérique et intelligente, révolution numérique et digitale, équipement numérisé et de haute intelligence

Effect of treatment with soda and dimethoxydimethylsilane on water absorption and thermal stability of olive pomace flour and date stone

In this article it was investigated the effect of chemical modification of the surface of olive pomace fiber and local date stones on their physical and thermal properties. The use of soda treatment, the dimethoxydimethylsilane, and alkaline pretreatment followed by treatment with dimethoxydimethylsilane fibers leads to an improvement of the thermal stability of the fibers and a reduced absorption of water, which allows us to recommend the use of its flour as fillers or reinforcements in the development of Wood Plastic Composite

Climate variability and storm impacts as major drivers for human coastal marsh withdrawal over the Neolithic period (Southern Brittany, NW France)

International audienceRelationships between climate variations, vegetation dynamics, and early human activities during the Neolithic have been reconstructed from high-resolution pollen and foraminiferal records obtained from cores retrieved from coastal wetland located in southern Brittany (Guidel, NW France). Our data show that the area around Guidel corresponded to a dense temperate forest locally replaced by riparian forest in the marsh, without any human disturbance during the early Neolithic. During the mid-Neolithic, between 6500 and 5500 cal years BP, the first episode of probable human settlement is recorded, as suggested by the increase of anthropogenic plants. This early record of human impact is consistent with archeological studies that find a high concentration of funeral monuments around Guidel during this cultural period. This complex first phase is interrupted by the disappearance of anthropogenic influence coinciding with a cold/humid climate period in the region characterized by recurrent major storms. Then, at the transition between the middle to late Neolithic, at 5500 cal years BP, a second phase of human retreat is signaled by both vegetation dynamics and archeological records; this interval also coincides with a climatic deterioration marked by cold/humid conditions recorded in the region (Sorrel et al., 2012). The results of the present study imply that human settlement/departure over the Neolithic was probably influenced by climatic variations. During the Bronze Age, Iron Age, and Middle Ages, a progressive decline of the arboreal forest synchronous with an increase of anthropogenic plants, confirms the high and persistent human activity around the site. Furthermore, our results at Guidel suggest a different anthropogenic trend recorded between north and south Brittany. The human impact is well recorded during the Neolithic at Guidel, while in northern Brittany human settlement is not recorded before the Bronze Age, consistent with existing archeological data

Coastal palaeoenvironmental record of the last 7 kyr BP in NW France: Sub-millennial climatic and anthropic Holocene signals

International audienceTo date, Holocene palaeoecological signatures on the Northwestern coast of France have not been thoroughly investigated. In this study, environmental changes related to both climate processes and human disturbances were reconstructed over the last 7000 cal. yr BP, based on pollen and chironomid assemblages from four coastal cores retrieved in Western Brittany (Porsmilin beach, NW France). Pollen and chironomid records show an environmental response to both millennial- and centennial-scale climate changes. During the mid-Holocene (until around 4200 cal. yr BP), when human impact was low, Porsmilin’s landscape was characterized by a mixed oak forest dominated by Corylus trees. Comparison of our data with other palynological data from the NW French Atlantic coast shows that this dominance may be related to more humid conditions prevailing at Porsmilin. Furthermore, over the mid-Holocene, Corylus and Quercus patterns appear anti-correlated, with Quercus declines appearing synchronous with major storms revealed by data recently compiled for the Holocene in Brittany, suggesting that cold conditions probably caused the Quercus contractions, which in turn favoured the rise of the heliophile taxon Corylus. Regarding chironomids over this period, our results show variations in lotic–lentic taxa related to hydrological conditions, more specifically changes in river run off strength. Over the Late Holocene, the Porsmilin palynological record shows progressive vegetation changes mainly related to human settlement and development of agricultural activities

Holocene paleoenvironmental changes in the Bay of Brest (NW France) over the last 6,500 years: palynological evidences of climate and human forcing.

International audienc