Search results for "Processes"
showing 10 items of 3831 documents
Mapping spatial patterns of denitrifiers for bridging community ecology and microbial processes along environmental gradients
2009
International audience; While there is ample evidence that microbial processes can exhibit large variations at a field scale, very little is known about the spatial distribution of the communities mediating these processes. The objective of this study was to explore spatial patterns of size and activity of the denitrifying community, a functional guild involved in N-cycling, in a grassland field subjected to different cattle grazing regimes. We used geostatistical modeling to map the distribution of size and activity of the denitrifier community in the pasture. Size of the denitrifier community was estimated by PCR quantification of the denitrification gene copy numbers while its activity w…
Millennial-scale terrestrial ecosystem responses to Upper Pleistocene climatic changes: 4D-reconstruction of the Schwalbenberg Loess-Palaeosol-Sequen…
2021
Abstract Loess-Palaeosol-Sequences (LPS) in the Central European region provide outstanding terrestrial polygenetic and multiphase archives responding to past climate and environments over various spatial and temporal scales. As yet, however, the geomorphological and pedogenic processes involved in LPS formation, and their interplay with changes in ecological conditions, impede robust correlation with other palaeoenvironmental archives. The Schwalbenberg LPS, which drape a hillslope in the Middle Rhine Valley in western Central Europe, provide unique high-resolution records highly suitable for investigating the processes involved in their formation and the relationship to climatic influence…
Recent extreme drought events in the Amazon rainforest: assessment of different precipitation and evapotranspiration datasets and drought indicators
2022
Over the last decades, the Amazon rainforest has been hit by multiple severe drought events. Here, we assess the severity and spatial extent of the extreme drought years 2005, 2010 and 2015/16 in the Amazon region and their impacts on the regional carbon cycle. As an indicator of drought stress in the Amazon rainforest, we use the widely applied maximum cumulative water deficit (MCWD). Evaluating nine state-of-the-art precipitation datasets for the Amazon region, we find that the spatial extent of the drought in 2005 ranges from 2.2 to 3.0 (mean =2.7) ×106 km2 (37 %–51 % of the Amazon basin, mean =45 %), where MCWD indicates at least moderate drought conditions (relative MCWD anomaly <-0…
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…
A complex thrust sequence in western Himalaya: the active Medlicott Wadia Thrust.
2017
15 pages; International audience; The recent activity of the Medlicott-Wadia Thrust (MWT) is investigated by geomorphic and tectonic studies in the Riasi zone, south of the Pir Panjal range (India, Jammu-Kasmir state of western Himalaya). In the Riasi area, the MWT forms a splay of five faults that dip northward. The recent activity of the splay is quantified using a set of deformed Quaternary alluvial units. The central branch of the thrust splay moved Precambrian limestones above Quaternary sediments and is sealed by 36 ± 3 ka (youngest OSL age) deposits. The other branches offset the top of a 15 ± 1 ka (youngest OSL age) alluvial fan by 180 to 120 m; the two southernmost branches form 17…
Body odors of newborns activate neuronal regions associated with reward in women
2010
abstract in symposium Cerebral Imaging in Taste and Olfaction; Olfactory signals are prime mediators of mother-infant bonding in. mammals, and they have been shown to be linked with maternal. attitudes and behavior in our own species as well. Human mothers. are indeed highly attentive to their infants odor cues, but although. we have good understanding of the neuronal network supporting. mother-infant olfactory recognition in various mammals, to date. no such information exists for humans. The present study is a first attempt at delineating the neural. network underlying the processing of infant odor properties by. women. Using functional magnetic resonance imaging (fMRI),. we measured the …
Response to all after conditioning to parts of the whole: a case of configural perception in the newborn rabbit
2012
Coming from flowers, foods or conspecifics, odours are ubiquitous in our environment. Most of the time, perceived odours are the result of complex relationships between tens or more of odorants with our olfactory system. Two perceptual strategies are potentially engaged to perceive such chemically complex mixtures. The elemental mode allows the perception of each component's quality. Conversely, the configural mode supports the perception of a new odour in addition to, or in place of, the odours of the components (blending effect). In humans, it is usually considered that the prevalence of one mode on the other is due, in part, to mixture complexity. In the rabbit, previous results have sho…
The role of taste and odour in the control of food intake: Unconscious impact of odors on food choices
2015
Invitation à un workshop et non en plénière; The role of taste and odour in the control of food intake: Unconscious impact of odors on food choices. 11. Pangborn sensory science symposium
Perceptual interactions in odour mixtures: The blending effect
2011
The odour perceived from a mixture of odorants varies depending on several factors as the context, individual physiological abilities, experience… but also as the perceptual interactions occurring over the processing of odorant mixtures. Sometimes, these interactions which appear during odour information coding and processing, lead to synergy or masking of odour notes (1). In other occasions, they lead to a blending effect. Odour blending appears when a mixture is perceived as a unique odour different from the odour of its components (1, 2). This type of mixture is well known by perfumers and flavourists who daily construct and use it in an empirical fashion. Here, we conducted a series of …
Both the number and perceptual quality of odorants control configural processing of odor mixture in human adults
2014
Both the number and perceptual quality of odorants control configural processing of odor mixture in human adults. 36. annual meeting - association for chemoreception sciences (AChemS XXXVI)