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991.
Yves T. Prairie Jukka Alm Jake Beaulieu Nathan Barros Tom Battin Jonathan Cole Paul del Giorgio Tonya DelSontro Frédéric Guérin Atle Harby John Harrison Sara Mercier-Blais Dominique Serça Sebastian Sobek Dominic Vachon 《Ecosystems》2018,21(5):1058-1071
Freshwater reservoirs are a known source of greenhouse gas (GHG) to the atmosphere, but their quantitative significance is still only loosely constrained. Although part of this uncertainty can be attributed to the difficulties in measuring highly variable fluxes, it is also the result of a lack of a clear accounting methodology, particularly about what constitutes new emissions and potential new sinks. In this paper, we review the main processes involved in the generation of GHG in reservoir systems and propose a simple approach to quantify the reservoir GHG footprint in terms of the net changes in GHG fluxes to the atmosphere induced by damming, that is, ‘what the atmosphere sees.’ The approach takes into account the pre-impoundment GHG balance of the landscape, the temporal evolution of reservoir GHG emission profile as well as the natural emissions that are displaced to or away from the reservoir site resulting from hydrological and other changes. It also clarifies the portion of the reservoir carbon burial that can potentially be considered an offset to GHG emissions. 相似文献
992.
Gabriel Sergio Costa Alves Luana Ferreira Torres Sinara Oliveira de Aquino Tharyn Reichel Luciana Perreira Freire Natalia Gomes Vieira Felipe Vinecky Dominique This David Pot Hervé Etienne Luciano Vilela Paiva Pierre Marraccini Alan Carvalho Andrade 《Tropical plant biology》2018,11(1-2):31-48
Climate change is posing a major challenge to coffee production worldwide leading to a need for the development of coffee cultivars with increased drought tolerance. In several plant species, the use of DREB genes in crop improvement has achieved promising results to desiccation tolerance engineering. Recent studies reported CcDREB1D specific patterns of expression in Coffea canephora and functional evidence of this gene involvement in drought stress responses. However, knowledge on natural diversity of this gene is largely unknown. In this context, this study aimed at evaluating the sequence variability of the DREB1D gene in several Coffea genotypes. Nucleotide variation in promoters and coding regions of this gene were evaluated in a population consisting of 38 genotypes of C. canephora, C. arabica and C. eugenioides, most of them characterized by different phenotypes (tolerance vs. susceptibility) in relation to drought. The genetic diversity of the loci revealed different haplotypes for the promoter and coding regions. In particular, our findings suggest association between drought tolerance and the genetic variations on DREB1D promoter regions, but not with those from its corresponding coding regions. Gene expression studies revealed up-regulated expression of DREB1D gene upon drought mainly in leaves of drought-tolerant clones of C. canephora, and in response to drought, high, and low temperatures in leaves of C. arabica, suggesting a key role of this gene in coffee responses to abiotic stress. 相似文献
993.
Sophie Calderari Massimiliano Ria Christelle Gérard Tatiane C. Nogueira Olatz Villate Stephan C. Collins Helen Neil Nicolas Gervasi Christophe Hue Nicolas Suarez-Zamorano Cécilia Prado Miriam Cnop Marie-Thérèse Bihoreau Pamela J. Kaisaki Jean-Baptiste Cazier Cécile Julier Mark Lathrop Michel Werner Dominique Gauguier 《Genomics》2018,110(2):98-111
The GLIS family zinc finger 3 isoform (GLIS3) is a risk gene for Type 1 and Type 2 diabetes, glaucoma and Alzheimer's disease endophenotype. We identified GLIS3 binding sites in insulin secreting cells (INS1) (FDR q < 0.05; enrichment range 1.40–9.11 fold) sharing the motif wrGTTCCCArTAGs, which were enriched in genes involved in neuronal function and autophagy and in risk genes for metabolic and neuro-behavioural diseases. We confirmed experimentally Glis3-mediated regulation of the expression of genes involved in autophagy and neuron function in INS1 and neuronal PC12 cells. Naturally-occurring coding polymorphisms in Glis3 in the Goto-Kakizaki rat model of type 2 diabetes were associated with increased insulin production in vitro and in vivo, suggestive alteration of autophagy in PC12 and INS1 and abnormal neurogenesis in hippocampus neurons. Our results support biological pleiotropy of GLIS3 in pathologies affecting β-cells and neurons and underline the existence of trans?nosology pathways in diabetes and its co-morbidities. 相似文献
994.
In Situ conservation of maize in Mexico: Genetic diversity and Maize seed management in a traditional community 总被引:2,自引:0,他引:2
Results from a study of maize varieties and seed sources in a traditional community in Jalisco, Mexico, raise questions about the relationship between genetic erosion and the introduction of varieties. The relevance of models for in situ conservation of crop genetic resources based on geographical isolation of a community is discussed. The morphophenological diversity of local materials is shown to be enhanced by introductions of both improved cultivars and landraces from farmers in other communities. On the other hand, the geographical point of reference for defining “local” landrace is shown to be larger than the community itself. Farmers will classify seed obtained from other farmers in and outside the community as that of a local landrace if it resembles their own according to the phenotypic characteristics they use to distinguish varieties. Maize diversity in this community is then the result of a certain level of introduction of genetic material and not of geographical isolation. 相似文献
995.
996.
997.
Florence Fouque Romuald Carinci Pascal Gaborit Jean Issaly Dominique J Bicout Philippe Sabatier 《Journal of vector ecology》2006,31(2):390-399
Field survival of Aedes aegypti females is a key parameter for estimating the dengue transmission potential of a mosquito population. The objectives of this study were to explore the dynamics of these survival rates at different times of the year in French Guiana and to analyze the results from the perspective of dengue patterns. The mosquitoes were captured, marked, released, and recaptured during four consecutive days in six houses every month, for three to 24 months, from January 1997 to December 1998. Laboratory experiments showed no effects on female survival but some effect on the survival of males. Females' daily survival in the field varied from 0.525 to 1 but was mostly between 0.8 and 0.95 during the entire year, with a mean value of 0.913. The field survival of Ae. aegypti females in French Guiana was thus in agreement with the likely transmission of dengue and the dengue endemic patterns throughout the year. On the other hand, heavy rainfalls during this time were less favorable to Ae. aegypti survival, which may explain part of the El Ni?o effect on dengue epidemics in French Guiana. The methods and results on Ae. aegypti survival will be implemented in a global dengue surveillance network in French Guiana. 相似文献
998.
999.
Food choice by white-tailed deer in relation to protein and energy content of the diet: a field experiment 总被引:3,自引:0,他引:3
Dominique Berteaux Michel Crête Jean Huot Jean Maltais Jean-Pierre Ouellet 《Oecologia》1998,115(1-2):84-92
Optimality models of food selection by herbivores assume that individuals are capable of assessing forage value, either directly
through the currency used in the model or indirectly through other variables correlated with the currency. Although energy
and protein are the two currencies most often used, controversy exists regarding their respective influence on food choice.
Part of the debate is due to the difficulty of teasing apart these two nutrients, which are closely correlated in most natural
forages. Here we offer a test of the assumption that energy and protein contents of the forage are both currencies that large
mammalian herbivores can use when selecting their food. We observed feeding behavior of 47 wild white-tailed deer (Odocoileusvirginianus) during winter while individuals were presented with four experimental foods representing two levels of energy and protein
(dry matter digestibility: 40–50%; crude protein: 12–16%). Using experimental foods allowed us to separate the influences
of energy and protein and clearly distinguish between the roles of these two nutrients. Deer discriminated between foods through
partial selection, and selected diets higher in energy but lower in protein. The observed choices appeared consistent with
physiological needs of deer wintering at the study site, where digestible energy was in short supply in the natural environment
while protein was probably not. Results are in good agreement with recent findings on domesticated ruminants. They support
a basic assumption of optimality models of food selection that use energy and/or protein as a currency, although the physiological
mechanisms behind the food selection process remain unclear. We urge students of food selection by herbivores to replicate
our experiment with other foods and/or in other circumstances before more general conclusions are drawn.
Received: 1 September 1997 / Accepted: 22 February 1998 相似文献
1000.
W. Courtens Dominique Grossman Nadine Van Roy Ludwine Messiaen Esther Vamos Veronique Toppet Dominique Haumont Catherine Streydio Anna Jauch Joris Robert Vermeesch Frank Speleman 《Human genetics》1998,103(4):497-505
We report on newborn monozygotic twins with a Noonan-like phenotype, and multiple congenital anomalies due to a monocentric
recombinant chromosome 18. The mother carried a paracentric inversion of the long arm of chromosome 18, inv(18)(q21.1q22.3).
Cytogenetic, fluorescent in situ hybridization, comparative genomic hybridization and DNA marker analyses allowed the delineation
of the deleted (18q22.3–qter) and duplicated (18q12.1–q21.1) chromosomal regions in the recombinant chromosome 18, and suggest
that this duplication-deletion chromosome 18 resulted from breakage of a dicentric recombinant chromosome 18 with subsequent
reconstitution of telomeric sequences on the long arm. Marked variability is observed in the phenotypic expression of the
same chromosomal anomaly in these monozygotic twins. The clinical findings of these patients are compared with those reported
in proximal 18q-duplication and distal 18q-deletion patients. The clinical features of both infants are compatible with Noonan
syndrome, suggesting that a locus for this syndrome may be located on the long arm of chromosome 18.
Received: 16 April 1998 / Accepted: 17 June 1998 相似文献