For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-al...For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem.展开更多
Background: Natural disturbance is a fundamental component of the functioning of tropical rainforests let to natural dynamics, with tree mortality the driving force of forest renewal. With ongoing global (i.e. land-...Background: Natural disturbance is a fundamental component of the functioning of tropical rainforests let to natural dynamics, with tree mortality the driving force of forest renewal. With ongoing global (i.e. land-use and climate) changes, tropical forests are currently facing deep and rapid modifications in disturbance regimes that may hamper their recovering capacity so that developing robust predictive model able to predict ecosystem resilience and recovery becomes of primary importance for decision-making: (i) Do regenerating forests recover faster than mature forests given the same level of disturbance? (ii) is the local topography an important predictor of the post-disturbance forest trajectories? (iii) Is the community functional composition, assessed with community weighted-mean functional traits, a good predictor of carbon stock recovery? (iv) How important is the climate stress (seasonal drought and/or soil water saturation) in shaping the recovery trajectory? Methods: Paracou is a large scale forest disturbance experiment set up in 1984 with nine 6.25 ha plots spanning on a large disturbance gradient where 15 to 60% of the initial forest ecosystem biomass were removed. More than 70,000 trees belonging to ca. 700 tree species have then been censused every 2 years up today. Using this unique dataset, we aim at deciphering the endogenous (forest structure and composition) and exogenous (local environment and climate stress) drivers of ecosystem recovery in time. To do so, we disentangle carbon recovery into demographic processes (recruitment, growth, mortality fluxes) and cohorts (recruited trees, survivors). Results: Variations in the pre-disturbance forest structure or in local environment do not shape significantly the ecosystem recovery rates. Variations in the pre-disturbance forest composition and in the post-disturbance climate significantly change the forest recovery trajectory. Pioneer-rich forests have slower recovery rates than assemblages of late-successional species. Soil water saturation during the wet season strongly impedes ecosystem recovery but not seasonal drought. From a sensitivity analysis, we highlight the pre-disturbance forest composition and the post-disturbance climate conditions as the primary factors controlling the recovery trajectory. Conclusions" Highly-disturbed forests and secondary forests because they are composed of a lot of pioneer species will be less able to cope with new disturbance. In the context of increasing tree mortality due to both (i) severe droughts imputable to climate change and (ii) human-induced perturbations, tropical forest management should focus on reducing disturbances by developing Reduced Impact Logging techniques.展开更多
<span style="font-family:Verdana;">The White-breasted Thrasher (</span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i&...<span style="font-family:Verdana;">The White-breasted Thrasher (</span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i><span></span></span></i><span style="font-family:Verdana;">) is the smallest passerine bird in the Mimids family.</span><span style="font-family:Verdana;"> Ranked as “endangered” in the IUCN list, the demographic distribution of this species is spread unevenly across two islands in the Lesser Antilles. The Saint-Lucian subspecies, <i></i></span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i> <i><span style="font-family:Verdana;">sanctaeluciae</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">, was estimated to number between 1200 and 1700 individuals, whereas the Martinique subspecies, <i></i></span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i> <i><span style="font-family:Verdana;">brachyurus</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">, was estimated at between 200 and 400 individuals. As an endemic rare species with a high risk of extinction, the Martinique subspecies should be regarded as a conservation priority. The small size of the Martinique subspecies population, its restricted geographical range, and its narrow habitat tolerance make it quite difficult to study. The variability of morphological traits in this subspecies has not been biostatistically analyzed recently. In</span><span style="font-family:Verdana;"> order to update knowledge and fill in any gaps, we have used the morphometric approach to study the morphological variability of the Martinique subspecies. The study site is a small peninsula located in the northeast of t</span><span style="font-family:Verdana;">he island of Martinique (French West Indies) known as “la Caravelle”. We captured 63 White-breasted Thrashers which were marked, measured, and sexed before being released. We did not observe any significant differences betwe</span><span style="font-family:Verdana;">en the sexes, signifying an absence of sexual dimorphism. However, we were able to observe a significant variation in morphological traits between individuals measured inside and outside the national protected area of Ca</span><span style="font-family:Verdana;">ravelle. The body mass-tarsus ratio was equal at both sampled sites, something which could potentially be a clue to the bird’s adaptation to different habitats.</span>展开更多
In this paper, we give sufficient conditions for the existence and uniqueness of asymptotically w-antiperiodic solutions for a nonlinear differential equation with piecewise constant argument in a Banach space when w ...In this paper, we give sufficient conditions for the existence and uniqueness of asymptotically w-antiperiodic solutions for a nonlinear differential equation with piecewise constant argument in a Banach space when w is an integer. This is done using the Banach fixed point theorem. An example involving the heat operator is discussed as an illustration of the theory.展开更多
The combined influence of maturation,ripening,and climate on the profile of bioactive compounds was studied in banana(Musa acuminata,AAA,Cavendish,cv.Grande Naine).Their bioactive compounds were determined by the Foli...The combined influence of maturation,ripening,and climate on the profile of bioactive compounds was studied in banana(Musa acuminata,AAA,Cavendish,cv.Grande Naine).Their bioactive compounds were determined by the Folin-Ciocalteu assay and high-performance thin layer chromatographic(HPTLC) method.The polyphenol content of bananas harvested after 400 degree days remained unchanged during ripening,while bananas harvested after 600 and 900 degree days exhibited a significant polyphenol increase.Although dopamine was the polyphenol with the highest concentration in banana peels during the green developmental stage and ripening,its kinetics differed from the total polyphenol profile.Our results showed that this matrix of choice(maturation,ripening,and climate) may allow selection of the banana(M.acuminata,AAA,Cavendish,cv.Grande Naine) status that will produce optimal concentrations of identified compounds with human health relevance.展开更多
文摘For a set S of real numbers, we introduce the concept of S-almost automorphic functions valued in a Banach space. It generalizes in particular the space of Z-almost automorphic functions. Considering the space of S-almost automorphic functions, we give sufficient conditions of the existence and uniqueness of almost automorphic solutions of a differential equation with a piecewise constant argument of generalized type. This is done using the Banach fixed point theorem.
基金funded by the GFclim project(FEDER 2014–2020,Project GY0006894)an Investissement d’avenir grant of the ANR(CEBA:ANR-10-LABEX-0025)
文摘Background: Natural disturbance is a fundamental component of the functioning of tropical rainforests let to natural dynamics, with tree mortality the driving force of forest renewal. With ongoing global (i.e. land-use and climate) changes, tropical forests are currently facing deep and rapid modifications in disturbance regimes that may hamper their recovering capacity so that developing robust predictive model able to predict ecosystem resilience and recovery becomes of primary importance for decision-making: (i) Do regenerating forests recover faster than mature forests given the same level of disturbance? (ii) is the local topography an important predictor of the post-disturbance forest trajectories? (iii) Is the community functional composition, assessed with community weighted-mean functional traits, a good predictor of carbon stock recovery? (iv) How important is the climate stress (seasonal drought and/or soil water saturation) in shaping the recovery trajectory? Methods: Paracou is a large scale forest disturbance experiment set up in 1984 with nine 6.25 ha plots spanning on a large disturbance gradient where 15 to 60% of the initial forest ecosystem biomass were removed. More than 70,000 trees belonging to ca. 700 tree species have then been censused every 2 years up today. Using this unique dataset, we aim at deciphering the endogenous (forest structure and composition) and exogenous (local environment and climate stress) drivers of ecosystem recovery in time. To do so, we disentangle carbon recovery into demographic processes (recruitment, growth, mortality fluxes) and cohorts (recruited trees, survivors). Results: Variations in the pre-disturbance forest structure or in local environment do not shape significantly the ecosystem recovery rates. Variations in the pre-disturbance forest composition and in the post-disturbance climate significantly change the forest recovery trajectory. Pioneer-rich forests have slower recovery rates than assemblages of late-successional species. Soil water saturation during the wet season strongly impedes ecosystem recovery but not seasonal drought. From a sensitivity analysis, we highlight the pre-disturbance forest composition and the post-disturbance climate conditions as the primary factors controlling the recovery trajectory. Conclusions" Highly-disturbed forests and secondary forests because they are composed of a lot of pioneer species will be less able to cope with new disturbance. In the context of increasing tree mortality due to both (i) severe droughts imputable to climate change and (ii) human-induced perturbations, tropical forest management should focus on reducing disturbances by developing Reduced Impact Logging techniques.
文摘<span style="font-family:Verdana;">The White-breasted Thrasher (</span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i><span></span></span></i><span style="font-family:Verdana;">) is the smallest passerine bird in the Mimids family.</span><span style="font-family:Verdana;"> Ranked as “endangered” in the IUCN list, the demographic distribution of this species is spread unevenly across two islands in the Lesser Antilles. The Saint-Lucian subspecies, <i></i></span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i> <i><span style="font-family:Verdana;">sanctaeluciae</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">, was estimated to number between 1200 and 1700 individuals, whereas the Martinique subspecies, <i></i></span><i><i><span style="font-family:Verdana;">Ramphocinclus</span></i><span> <i><span style="font-family:Verdana;">brachyurus</span></i> <i><span style="font-family:Verdana;">brachyurus</span></i><span style="font-family:Verdana;"></span></span></i><span style="font-family:Verdana;">, was estimated at between 200 and 400 individuals. As an endemic rare species with a high risk of extinction, the Martinique subspecies should be regarded as a conservation priority. The small size of the Martinique subspecies population, its restricted geographical range, and its narrow habitat tolerance make it quite difficult to study. The variability of morphological traits in this subspecies has not been biostatistically analyzed recently. In</span><span style="font-family:Verdana;"> order to update knowledge and fill in any gaps, we have used the morphometric approach to study the morphological variability of the Martinique subspecies. The study site is a small peninsula located in the northeast of t</span><span style="font-family:Verdana;">he island of Martinique (French West Indies) known as “la Caravelle”. We captured 63 White-breasted Thrashers which were marked, measured, and sexed before being released. We did not observe any significant differences betwe</span><span style="font-family:Verdana;">en the sexes, signifying an absence of sexual dimorphism. However, we were able to observe a significant variation in morphological traits between individuals measured inside and outside the national protected area of Ca</span><span style="font-family:Verdana;">ravelle. The body mass-tarsus ratio was equal at both sampled sites, something which could potentially be a clue to the bird’s adaptation to different habitats.</span>
文摘In this paper, we give sufficient conditions for the existence and uniqueness of asymptotically w-antiperiodic solutions for a nonlinear differential equation with piecewise constant argument in a Banach space when w is an integer. This is done using the Banach fixed point theorem. An example involving the heat operator is discussed as an illustration of the theory.
基金Project supported by the French Region Country Government of Guadeloupe using the long term fellowships provided with the European Social Fund 2007-2013
文摘The combined influence of maturation,ripening,and climate on the profile of bioactive compounds was studied in banana(Musa acuminata,AAA,Cavendish,cv.Grande Naine).Their bioactive compounds were determined by the Folin-Ciocalteu assay and high-performance thin layer chromatographic(HPTLC) method.The polyphenol content of bananas harvested after 400 degree days remained unchanged during ripening,while bananas harvested after 600 and 900 degree days exhibited a significant polyphenol increase.Although dopamine was the polyphenol with the highest concentration in banana peels during the green developmental stage and ripening,its kinetics differed from the total polyphenol profile.Our results showed that this matrix of choice(maturation,ripening,and climate) may allow selection of the banana(M.acuminata,AAA,Cavendish,cv.Grande Naine) status that will produce optimal concentrations of identified compounds with human health relevance.