Crohn's disease (CD) is a chronic inflammatory disease of the digestive tract with systemic manifestations. Etiology is unknown, even if immunological, genetic and environmental factors are involved. The majority ...Crohn's disease (CD) is a chronic inflammatory disease of the digestive tract with systemic manifestations. Etiology is unknown, even if immunological, genetic and environmental factors are involved. The majority of CD patients require surgery during their lifetime due to progressive bowel damage, but, even when all macroscopic lesions have been removed by surgery, the disease recurs in most cases. Postoperative management represents therefore a crucial mean for preventing recurrence. Several drugs and approaches have been proposed to achieve this aim. Endoscopic inspection of the ileocolic anastomosis within 1 year from surgery is widely encouraged, given that endoscopic recurrence is one of the greatest predictors for clinical recurrence. A strategy should be planned only after stratifying patients according to their individual risk of recurrence, avoiding unnecessary therapies when possible benefits are reduced, and selecting high-risk patients for more aggressive intervention.展开更多
Aims Intraspecific variation in plant traits has important consequences for individual fitness and herbivore foraging.For plants,trait variability across spatial dimensions is well documented.However,temporal dimensio...Aims Intraspecific variation in plant traits has important consequences for individual fitness and herbivore foraging.For plants,trait variability across spatial dimensions is well documented.However,temporal dimensions of trait variability are less well known,and may be influenced by seasonal differences in growing degree days(GDD),temperature and precipitation.Here,we aim to quantify intraspecific temporal variation in traits and the underlying drivers for four commonly occurring boreal plant species.Methods We sampled the elemental and stoichiometric traits(%C,%N,%P,C:N,C:P,N:P)of four common browse species'foliage across 2 years.Using a two-step approach,we first fitted generalized linear models(GzLM,n=24)to the species'elemental and stoichiometric traits,and tested if they varied across years.When we observed evidence for temporal variability,we fitted a second set of GzLMs(n=8)with temperature,productivity and moisture as explanatory variables.Important Findings We found no evidence of temporal variation for most of the elemental and stoichiometric traits of our four boreal plants,with two exceptions.Year was an important predictor for percent carbon across all four species(R^(2)=0.47-0.67)and for multiple elemental and stoichiometric traits in balsam fir(5/8,R2=0.29-0.67).Thus,variation in percent carbon was related to interannual differences,more so than nitrogen and phosphorus,which are limiting nutrients in the boreal forest.These results also indicate that year may explain more variation in conifers'stoichiometry than for deciduous plants due to life history differences.GDD was the most frequently occurring variable in the second round of models(8/8 times,R^(2)=0.21-0.41),suggesting that temperature is an important driver of temporal variation in these traits.展开更多
文摘Crohn's disease (CD) is a chronic inflammatory disease of the digestive tract with systemic manifestations. Etiology is unknown, even if immunological, genetic and environmental factors are involved. The majority of CD patients require surgery during their lifetime due to progressive bowel damage, but, even when all macroscopic lesions have been removed by surgery, the disease recurs in most cases. Postoperative management represents therefore a crucial mean for preventing recurrence. Several drugs and approaches have been proposed to achieve this aim. Endoscopic inspection of the ileocolic anastomosis within 1 year from surgery is widely encouraged, given that endoscopic recurrence is one of the greatest predictors for clinical recurrence. A strategy should be planned only after stratifying patients according to their individual risk of recurrence, avoiding unnecessary therapies when possible benefits are reduced, and selecting high-risk patients for more aggressive intervention.
基金This research was funded by the Government of Newfoundland and Labrador Centre for Forest Science Innovation(CFSI)Memorial University of Newfoundland SEEDS funding to S.J.L.,E.V.W.and Y.F.W.+3 种基金Mitacs Accelerate Grant to Y.F.W.,S.J.L.and E.V.W.Canada Foundation for Innovation funding to Y.F.W.(13025)the Natural Sciences and Engineering Research Council of Canada(Discovery Grant RGPIN-2015-05799 to Y.F.W.)In-kind support was provided by Parks Canada-Terra Nova National Park and the CFSI,with thanks to Janet Feltham and Blair Adams.
文摘Aims Intraspecific variation in plant traits has important consequences for individual fitness and herbivore foraging.For plants,trait variability across spatial dimensions is well documented.However,temporal dimensions of trait variability are less well known,and may be influenced by seasonal differences in growing degree days(GDD),temperature and precipitation.Here,we aim to quantify intraspecific temporal variation in traits and the underlying drivers for four commonly occurring boreal plant species.Methods We sampled the elemental and stoichiometric traits(%C,%N,%P,C:N,C:P,N:P)of four common browse species'foliage across 2 years.Using a two-step approach,we first fitted generalized linear models(GzLM,n=24)to the species'elemental and stoichiometric traits,and tested if they varied across years.When we observed evidence for temporal variability,we fitted a second set of GzLMs(n=8)with temperature,productivity and moisture as explanatory variables.Important Findings We found no evidence of temporal variation for most of the elemental and stoichiometric traits of our four boreal plants,with two exceptions.Year was an important predictor for percent carbon across all four species(R^(2)=0.47-0.67)and for multiple elemental and stoichiometric traits in balsam fir(5/8,R2=0.29-0.67).Thus,variation in percent carbon was related to interannual differences,more so than nitrogen and phosphorus,which are limiting nutrients in the boreal forest.These results also indicate that year may explain more variation in conifers'stoichiometry than for deciduous plants due to life history differences.GDD was the most frequently occurring variable in the second round of models(8/8 times,R^(2)=0.21-0.41),suggesting that temperature is an important driver of temporal variation in these traits.
