Search results for "RESPIRATORY SYSTEM"
showing 10 items of 1829 documents
Spatial models for monitoring the spatio-temporal evolution of ashes after fire-a case study of a burnt grassland in Lithuania
2013
Ash thickness is a key variable in the protection of soil against erosion agents after planned and unplanned fires. Ash thickness measurements were conducted along two transects (flat and sloping areas) following a grided experimental design. In order to interpolate data with accuracy and identify the techniques with the least bias, several interpolation methods were tested in the grided plot. Overall, the fire had a low severity. However, the fire significantly reduced the ground cover, especially on sloping areas, owing to the higher fire severity and/or less biomass previous to the fire. Ash thickness depended on fire severity and was thin where fire severity was higher and thicker in lo…
"Table 2" of "Measurement of differential Z / gamma* + jet + X cross sections in p anti-p collisions at s**(1/2) = 1.96-TeV"
2008
Measured cross section as a function of the jet rapidity.
Erosion of biodiversity affects the stability of soil microbial communities
2012
Anthropogenic activities have led to a significant modification/reduction of biodiversity. By observing this erosion, the understanding of the relationship between biodiversity and ecosystem functioning has emerged as a central issue in ecological and environmental sciences during the last decade. This relationship between diversity-stability-function has been extensively studied by plant ecologists, but remains largely unexplored for soil microorganisms. In this context, we studied the impact of an erosion of biodiversity on the stability of soil microbial communities (i.e. resistance and resilience) in response to two perturbations: a residual metallic stress (mercury input at 20 ppm) and…
Reduction of nitrate leaching: what is the contribution of the residual weed flora?
2018
International audience; Integrated crop protection tolerates residual weeds if they are not harmful for crop production. Weeds are often solely considered as a pest, causing crop yield loss, harvest pollution, diseases … However, they may also provide beneficial services for agroecosystems, promoting plant biodiversity and feeding other organisms potentially beneficial to crop production (pollinators, carabids…). The role of residual weed flora as nitrate catchers, during summer fallow, has however rarely been assessed. Yet, some weed species are known for their high potential to take up soil nitrogen. The present study aimed to (1) develop an indicator to account for the potential benefici…
Loss in microbial diversity affects nitrogen cycling in soil
2013
International audience; Microbial communities have a central role in ecosystem processes by driving the Earth's biogeochemical cycles. However, the importance of microbial diversity for ecosystem functioning is still debated. Here, we experimentally manipulated the soil microbial community using a dilution approach to analyze the functional consequences of diversity loss. A trait-centered approach was embraced using the denitrifiers as model guild due to their role in nitrogen cycling, a major ecosystem service. How various diversity metrics related to richness, eveness and phylogenetic diversity of the soil denitrifier community were affected by the removal experiment was assessed by 454 s…
A theoretical study of the wet removal of atmospheric pollutants. Part I: the redistribution of aerosol particles captured through nucleation and imp…
1985
Abstract A theoretical model is formulated which allows the processes that control the wet deposition of atmospheric pollutants to be included in cloud dynamic models. The model considers the condensation process and the collision-coalescence process which, coupled together, control the fate of atmospheric aerosol particles removed by clouds and precipitation through nucleation scavenging and impaction scavenging. The model was tested by substituting a simple parcel model for the dynamic framework. In this form the model was used to determine the time evolution of the aerosol particle mass scavenged by drops as well as the aerosol particle mass left unactivated in air as “drop-interstitial”…
Identification et spécificité d’espèce des protéines d’intérêt pour le diagnostic sérologique de la maladie du poumon d’éleveur d’oiseaux
2016
Introduction La maladie du poumon d’eleveur d’oiseaux (PEO) est une pneumopathie d’hypersensibilite liee a l’inhalation repetee de proteines antigeniques localisees entre autre, dans les fientes des oiseaux. Actuellement on connait peu de chose sur la nature de ces proteines. La serologie occupe une place importante dans le diagnostic, toutefois, celle-ci manque de specificite et de standardisation. Les objectifs consistent a evaluer la specificite des proteines antigeniques impliquees dans le PEO vis-a-vis de differentes especes aviaires et a identifier les proteines d’interet contenues dans les fientes de pigeon. Methodes Une comparaison des proteines des fientes de deux races de pigeon, …
What is the contribution of the residual weed floras to reduce nitrate leaching?
2018
International audience; Integrated crop protection tolerates residual weed floras if they are not harmful for crop production. Weeds are often solely considered with a negative viewpoint, but they may also provide beneficial services for agroecosystems, such as plant biodiversity promotion and trophic resources for other organisms such as pollinators. The role of residual weed flora as nitrate catchers, during the summer fallow, has seldomly been assessed, in spite of the high potential of some weed species to take up nitrogen. The present study aimed to (1) develop an indicator to account for the potential role of weed floras as nitrate catchers at the field scale, and (2) calculate this i…
Microbial diversity and structure are drivers of the biological barrier effect against Listeria monocytogenes in soil
2013
International audience; Understanding the ecology of pathogenic organisms is important in order to monitor their transmission in the environment and the related health hazards. We investigated the relationship between soil microbial diversity and the barrier effect against Listeria monocytogenes invasion. By using a dilution-to-extinction approach, we analysed the consequence of eroding microbial diversity on L. monocytogenes population dynamics under standardised conditions of abiotic parameters and microbial abundance in soil microcosms. We demonstrated that highly diverse soil microbial communities act as a biological barrier against L. monocytogenes invasion and that phylogenetic compos…
Weed cohort succession as a main driver of weed diversity dynamic throughout winter cereal cropping season in both presence and absence of crop speci…
2017
EAGESTAD INRA; Ecological succession theory predicts that soon after disturbance, community diversity results from species colonization while competitive interaction plays an increasing influential with time since disturbance. While weeds species in arable fields face frequent disturbances, they also face intense competition for light as they are over-dominated by the crop species. Thus, both colonization and competition may shape weeds community diversity in arable fields. Using a semi-experimental approach, we analysis the evolution of weed diversity throughout time in 56 winter cereal cropping seasons. We use the crop sowing date as proxy of the last disturbance. We predict that in the a…