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71.
Costa Marcela Porto Chadwick David Saget Sophie Rees Robert M. Williams Michael Styles David 《The International Journal of Life Cycle Assessment》2020,25(10):1942-1956
The International Journal of Life Cycle Assessment - There is an imperative to accurately assess the environmental sustainability of crop system interventions in the context of food security and... 相似文献
72.
Rene M. van der Zande Michelle Achlatis Dorothea Bender‐Champ Andreas Kubicek Sophie Dove Ove Hoegh‐Guldberg 《Global Change Biology》2020,26(4):2203-2219
Despite recent efforts to curtail greenhouse gas emissions, current global emission trajectories are still following the business‐as‐usual representative concentration pathway (RCP) 8.5 emission pathway. The resulting ocean warming and acidification have transformative impacts on coral reef ecosystems, detrimentally affecting coral physiology and health, and these impacts are predicted to worsen in the near future. In this study, we kept fragments of the symbiotic corals Acropora intermedia (thermally sensitive) and Porites lobata (thermally tolerant) for 7 weeks under an orthogonal design of predicted end‐of‐century RCP8.5 conditions for temperature and pCO2 (3.5°C and 570 ppm above present‐day, respectively) to unravel how temperature and acidification, individually or interactively, influence metabolic and physiological performance. Our results pinpoint thermal stress as the dominant driver of deteriorating health in both species because of its propensity to destabilize coral–dinoflagellate symbiosis (bleaching). Acidification had no influence on metabolism but had a significant negative effect on skeleton growth, particularly when photosynthesis was absent such as in bleached corals or under dark conditions. Total loss of photosynthesis after bleaching caused an exhaustion of protein and lipid stores and collapse of calcification that ultimately led to A. intermedia mortality. Despite complete loss of symbionts from its tissue, P. lobata maintained small amounts of photosynthesis and experienced a weaker decline in lipid and protein reserves that presumably contributed to higher survival of this species. Our results indicate that ocean warming and acidification under business‐as‐usual CO2 emission scenarios will likely extirpate thermally sensitive coral species before the end of the century, while slowing the recovery of more thermally tolerant species from increasingly severe mass coral bleaching and mortality. This could ultimately lead to the gradual disappearance of tropical coral reefs globally, and a shift on surviving reefs to only the most resilient coral species. 相似文献
73.
Grégory Dubar Elie Azria Antoine Tesnière Hervé Dupont Camille Le Ray Thomas Baugnon Sophie Matheron Dominique Luton Jean-Christophe Richard Odile Launay Vassilis Tsatsaris Fran?ois Goffinet Alexandre Mignon for the French Registry on A/HNv during pregnancy 《PloS one》2010,5(10)
Background
The first reports on the pandemic influenza 2009 A/H1N1v from the USA, Mexico, and Australia indicated that this disease was associated with a high mortality in pregnant women. The aim of this study was to describe and compare the characteristics of severe critically ill and non-severe pregnant women with 2009 A/H1N1v-related illness in France.Methodology/Principal Findings
A national registry was created to screen pregnant women with laboratory-confirmed 2009 A/H1N1v influenza. Three hundred and fifteen patients from 46 French hospitals were included: 40 patients were admitted to intensive care units (severe outcomes), 111 were hospitalized in obstetric or medical wards (moderate outcomes), and 164 were outpatients (mild outcomes). The 2009 A/H1N1v influenza illness occurred during all pregnancy trimesters, but most women (54%), notably the severe patients (70%), were in the third trimester. Among the severe patients, twenty (50%) underwent mechanical ventilation, and eleven (28%) were treated with extracorporeal membrane oxygenation. Three women died from A/H1N1v influenza. We found a strong association between the development of a severe outcome and both co-existing illnesses (adjusted odds ratio [OR], 5.1; 95% confidence interval [CI], 2.2–11.8) and a delay in oseltamivir treatment after the onset of symptoms (>3 or 5 days) (adjusted OR, 4.8; 95% CI, 1.9–12.1 and 61.2, 95% CI; 14.4–261.3, respectively). Among the 140 deliveries after 22 weeks of gestation known to date, 19 neonates (14%) were admitted to a neonatal intensive care unit, mainly for preterm delivery, and two neonates died. None of these neonates developed 2009 A/H1N1v infection.Conclusions
This series confirms the high incidence of complications in pregnant women infected with pandemic A/H1N1v observed in other countries but depicts a lower overall maternal and neonatal mortality and morbidity than indicated in the USA or Australia. Moreover, our data demonstrate the benefit of early oseltamivir treatment in this specific population. 相似文献74.
75.
Salima Machkour-M’Rabet Yann Hénaut Sophie Calmé Luc Legal 《Journal of Insect Conservation》2012,16(4):479-488
Landscape fragmentation usually has a considerable effect on the genetic and demographic viability of most species because it reduces population size and increases isolation among populations. This situation provokes loss of genetic diversity and increased inbreeding that can lead to population or species extinctions. Some studies also show that landscape fragmentation may have no effect on or even positive consequences for species genetic diversity. The protected tarantula, Brachypelma vagans, exhibits a particular situation in the Mexican Caribbean, which has experienced high lowland and coastal fragmentation because of recent increases in agricultural, urban and touristic development. This modified landscape structure creates favorable conditions for establishment of B. vagans populations in rural settlements. Populations of this tarantula have high densities of individuals, principally females and juveniles, and gene dispersion is assumed by the rare males. Within this context, we studied the influence of natural and anthropogenic fragmentation on the genetic diversity of six B. vagans populations (five continental, one insular), together with their spatial organization. Our approach used seven inter simple sequence repeat markers, which are highly polymorphic markers. The 76 loci selected revealed high genetic variability for continental populations and a low, but not critical situation, for the insular population. We detected a good level of gene exchange among continental populations, and an evident and recent isolation of the island population. This species exhibits a metapopulation structure in the lowlands with numerous local populations where mature females exhibit high birth site fidelity. We conclude that this protected species does not exhibit characteristics to warrant its current conservation status, and we propose complete revision of the ecological and genetic situation for B. vagans in particular, and for all species within the genus Brachypelma in general. 相似文献
76.
Sagnard F Deu M Dembélé D Leblois R Touré L Diakité M Calatayud C Vaksmann M Bouchet S Mallé Y Togola S Traoré PC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2011,123(7):1231-1246
Gene flow between domesticated plants and their wild relatives is one of the major evolutionary processes acting to shape their structure of genetic diversity. Earlier literature, in the 1970s, reported on the interfertility and the sympatry of wild, weedy and cultivated sorghum belonging to the species Sorghum bicolor in most regions of sub-Saharan Africa. However, only a few recent surveys have addressed the geographical and ecological distribution of sorghum wild relatives and their genetic structure. These features are poorly documented, especially in western Africa, a centre of diversity for this crop. We report here on an exhaustive in situ collection of wild, weedy and cultivated sorghum assembled in Mali and in Guinea. The extent and pattern of genetic diversity were assessed with 15 SSRs within the cultivated pool (455 accessions), the wild pool (91 wild and weedy forms) and between them. F (ST) and R (ST) statistics, distance-based trees, Bayesian clustering methods, as well as isolation by distance models, were used to infer evolutionary relationships within the wild-weedy-crop complex. Firstly, our analyses highlighted a strong racial structure of genetic diversity within cultivated sorghum (F (ST) = 0.40). Secondly, clustering analyses highlighted the introgressed nature of most of the wild and weedy sorghum and grouped them into two eco-geographical groups. Such closeness between wild and crop sorghum could be the result of both sorghum's domestication history and preferential post-domestication crop-to-wild gene flow enhanced by farmers' practices. Finally, isolation by distance analyses showed strong spatial genetic structure within each pool, due to spatially limited dispersal, and suggested consequent gene flow between the wild and the crop pools, also supported by R (ST) analyses. Our findings thus revealed important features for the collection, conservation and biosafety of domesticated and wild sorghum in their centre of diversity. 相似文献
77.
For more than 80 years, subtyping of Salmonella enterica has been routinely performed by serotyping, a method in which surface antigens are identified based on agglutination reactions with specific antibodies. The serotyping scheme, which is continuously updated as new serovars are discovered, has generated over time a data set of the utmost significance, allowing long-term epidemiological surveillance of Salmonella in the food chain and in public health control. Conceptually, serotyping provides no information regarding the phyletic relationships inside the different Salmonella enterica subspecies. In epidemiological investigations, identification and tracking of salmonellosis outbreaks require the use of methods that can fingerprint the causative strains at a taxonomic level far more specific than the one achieved by serotyping. During the last 2 decades, alternative methods that could successfully identify the serovar of a given strain by probing its DNA have emerged, and molecular biology-based methods have been made available to address phylogeny and fingerprinting issues. At the same time, accredited diagnostics have become increasingly generalized, imposing stringent methodological requirements in terms of traceability and measurability. In these new contexts, the hand-crafted character of classical serotyping is being challenged, although it is widely accepted that classification into serovars should be maintained. This review summarizes and discusses modern typing methods, with a particular focus on those having potential as alternatives for classical serotyping or for subtyping Salmonella strains at a deeper level. 相似文献
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