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121.
Liñero Olaia Cornu Jean-Yves de Diego Alberto Bussière Sylvie Coriou Cécile Thunot Stéphane Robert Thierry Nguyen Christophe 《Plant and Soil》2018,424(1-2):435-450
Plant and Soil - This study investigated the possible source organs delivering several trace elements to seeds (root uptake versus net remobilization), by studying changes in biomass and element... 相似文献
122.
The new fossil locality of El Kohol is located on the southern flank of the Saharan Altas, near Brezina (Algeria). It has been discovered in a thick Palaeogene continental series divided into 4 members: a transitional gypsiferous member, a lower red detritic member, a middle marly-calcareous member, and an upper red detritic member. The new flora and fauna have been obtained by excavation and washing-screening of a marly level of the middle member. The main finds are charophytes, lower vertebrates, a marsupial and eutherian mammals (lipotyphlan Insectivora, hyracoids, creodonts and Proboscidea). Geological and palaeontological data allow to refer these fossil remains, at least provisorily, to the end of the early Eocene. Palaeobiogeographical comments are made about forms with Holarctic affinities. 相似文献
123.
Yohan M. Charbonnier Luc Barbaro Jean-Yves Barnagaud Evy Ampoorter Julien Nezan Kris Verheyen Hervé Jactel 《Oecologia》2016,180(2):529-542
Species assemblages are shaped by local and continental-scale processes that are seldom investigated together, due to the lack of surveys along independent gradients of latitude and habitat types. Our study investigated changes in the effects of forest composition and structure on bat and bird diversity across Europe. We compared the taxonomic and functional diversity of bat and bird assemblages in 209 mature forest plots spread along gradients of forest composition and vertical structure, replicated in 6 regions spanning from the Mediterranean to the boreal biomes. Species richness and functional evenness of both bat and bird communities were affected by the interactions between latitude and forest composition and structure. Bat and bird species richness increased with broadleaved tree cover in temperate and especially in boreal regions but not in the Mediterranean where they increased with conifer abundance. Bat species richness was lower in forests with smaller trees and denser understorey only in northern regions. Bird species richness was not affected by forest structure. Bird functional evenness increased in younger and denser forests. Bat functional evenness was also influenced by interactions between latitude and understorey structure, increasing in temperate forests but decreasing in the Mediterranean. Covariation between bat and bird abundances also shifted across Europe, from negative in southern forests to positive in northern forests. Our results suggest that community assembly processes in bats and birds of European forests are predominantly driven by abundance and accessibility of feeding resources, i.e., insect prey, and their changes across both forest types and latitudes. 相似文献
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125.
Identification of Multiple Protective Epitopes (Protectopes) in the Central Conserved Domain of a Prototype Human Respiratory Syncytial Virus G Protein 总被引:2,自引:0,他引:2
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Hlne Plotnicky-Gilquin Liliane Goetsch Thierry Huss Thierry Champion Alain Beck Jean-Franois Haeuw Thien Ngoc Nguyen Jean-Yves Bonnefoy Nathalie Corvaïa Ultan F. Power 《Journal of virology》1999,73(7):5637-5645
A recombinant fusion protein (BBG2Na) comprising the central conserved domain of the respiratory syncytial virus subgroup A (RSV-A) (Long) G protein (residues 130 to 230) and an albumin binding domain of streptococcal protein G was shown previously to protect mouse upper (URT) and lower (LRT) respiratory tracts against intranasal RSV challenge (U. F. Power, H. Plotnicky-Gilquin, T. Huss, A. Robert, M. Trudel, S. Stahl, M. Uhlén, T. N. Nguyen, and H. Binz, Virology 230:155-166, 1997). Panels of monoclonal antibodies (MAbs) and synthetic peptides were generated to facilitate dissection of the structural elements of this domain implicated in protective efficacy. All MAbs recognized native RSV-A antigens, and five linear B-cell epitopes were identified; these mapped to residues 152 to 163, 165 to 172, 171 to 187 (two overlapping epitopes), and 196 to 204, thereby covering the highly conserved cysteine noose domain. Antibody passive-transfer and peptide immunization studies revealed that all epitopes were implicated in protection of the LRT, but not likely the URT, against RSV-A challenge. Pepscan analyses of anti-RSV-A and anti-BBG2Na murine polyclonal sera revealed lower-level epitope usage within the central conserved region in the former, suggesting diminished immunogenicity of the implicated epitopes in the context of the whole virus. However, Pepscan analyses of RSV-seropositive human sera revealed that all of the murine B-cell protective epitopes (protectopes) that mapped to the central conserved domain were recognized in man. Should these murine protectopes also be implicated in human LRT protection, their clustering around the highly conserved cysteine noose region will have important implications for the development of RSV vaccines. 相似文献
126.
G V Dimitrov T I Arabadzhiev J-Y Hogrel N A Dimitrova 《Journal of electromyography and kinesiology》2008,18(1):35-43
Capabilities of amplitude and spectral methods for information extraction from interference EMG signals were assessed through simulation and preliminary experiment. Muscle was composed of 4 types of motor units (MUs). Different hypotheses on changes in firing frequency of individual MUs, intracellular action potential (IAP) and muscle fibre propagation velocity (MFPV) during fatigue were analyzed. It was found that changes in amplitude characteristics of interference signals (root mean square, RMS, or integrated rectified value, IEMG) detected by intramuscular and surface electrodes differed. RMS and IEMG of surface detected interference signals could increase even under MU firing rate reduction and without MU synchronisation. IAP profile lengthening can affect amplitude characteristics more significantly than MU firing frequency. Thus, an increase of interference EMG amplitude is unreliable to reflect changes in the neural drive. The ratio between EMG amplitude and contraction response can hardly characterise the so-called 'neuromuscular efficiency'. The recently proposed spectral fatigue indices can be used for quantification of interference EMG signals. The indices are practically insensitive to MU firing frequency. IAP profile lengthening and decrease in MFPV enhanced the index value, while recruitment of fast fatigable MUs reduced it. Sensitivity of the indices was higher than that of indices traditionally used. 相似文献
127.
Abdo MR Joseph P Boigegrain RA Montero JL Köhler S Winum JY 《Journal of enzyme inhibition and medicinal chemistry》2008,23(3):357-361
Histidinol dehydrogenase (HDH, EC EC1.1.1.23) catalyses the final step in the biosynthesis of histidine and constitutes an attractive novel target for the development of new agents against the pathogenous, bacteria Brucella suis. A small library of new HDH inhibitors based on the L-histidinylphenylsulfonyl hydrazide scaffold has been synthesized and their inhibitory activity investigated. The obtained results demonstrate that modification of the group between the histidinyl moiety and the phenyl ring constitutes an important structural factor for the design of effective HDH inhibitors. 相似文献
128.
129.
Marie-Pierre Forquin Hugo Duvergey Caroline Proux Valentin Loux Jerome Mounier Sophie Landaud Jean-Yves Coppée Jean-Fran?ois Gibrat Pascal Bonnarme Isabelle Martin-Verstraete Tatiana Vallaeys 《Applied and environmental microbiology》2009,75(19):6406-6409
Multilocus sequence typing with nine selected genes is shown to be a promising new tool for accurate identifications of Brevibacteriaceae at the species level. A developed microarray also allows intraspecific diversity investigations of Brevibacterium aurantiacum showing that 13% to 15% of the genes of strain ATCC 9174 were absent or divergent in strain BL2 or ATCC 9175.Brevibacteriaceae play a major part in the cheese smear community (6, 11). The classification and typing of cheese-related Brevibacteriaceae have been based mainly on molecular methods such as amplified ribosomal DNA restriction enzyme analysis, pulsed-field gel electrophoresis, and ribotyping (8, 10, 12). Recently, the original Brevibacterium linens group was split into two species on the basis of their physiological and biochemical characteristics, the sugar and polyol composition of their teichoic acids, and their 16S rRNA sequence and DNA-DNA hybridization levels. One species remains B. linens and is represented by type strain ATCC 9172. The other, represented by type strain ATCC 9175, has been renamed Brevibacterium aurantiacum. Regarding this new classification, the taxonomic position of cheese-related isolates has to be revisited and potential relationships between phylogenetic affiliation and the potential occurrence of given metabolic characteristics redefined (7). The unfinished genome sequence of B. aurantiacum ATCC 9174 has recently been released by the Joint Genome Institute (http://genome.jgi-psf.org/draft_microbes/breli/breli.home.html). The development of focused phylogenetic approaches using multiple markers in conjunction with whole-genome screening techniques such as comparative genomic hybridization (CGH) has proven to be useful for the detailed characterization of pathogenic species, including food pathogens (3, 5, 9). However, only a few technological species have been investigated at an intraspecies level (2). Our intention was thus to develop modern tools to facilitate the typing of strains of technological interest, for which Brevibacteriaceae could be used as a case study. 相似文献
130.
Anne-Laure Brochet Michel Gauthier-Clerc Raphaël Mathevet Arnaud Béchet Jean-Yves Mondain-Monval Alain Tamisier 《Biodiversity and Conservation》2009,18(7):1879-1894
Many wild species, like waterbirds, are exploited for their economic interests. At present, the annual western Palearctic
duck bag is at least 17 million birds. From a sustainable management perspective, wetland users and managers request predictions
of spatial distribution and abundance variations of these bird populations. The objective of this study was to analyze local
factors potentially influencing the diurnal distribution and population size of wintering ducks and coots, the main game species,
in Camargue (southern France). First, we showed that marshland surface area, salinity and hunting disturbance were the principal
variables explaining the duck and coot distribution. Secondly, we tested the hypothesis that hunting disturbance would reduce
the carrying capacity of the Camargue with two analyses: the effect of creating a protected area and the change of the hunting
closing date. This hypothesis was not validated. Our study therefore led us to reconsider the research orientations on the
carrying capacity in this wetland. The surface of protected day roosts seems presently sufficient in the Rhone delta. Consequently,
to increase the population size with the same level of hunting disturbance at the scale of the Camargue, alternative strategies
should be envisaged, such as the creation of nature reserves on nocturnal feeding ground or the creation of large management
units with limited disturbance. 相似文献