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This article describes a multi-modal routing problem, which occurs each time a user wants to travel from a point A to a point B, using either ride-sharing or public transportation. The main idea is to start from an itinerary using public transportation, and then substitute part of this itinerary by ride-sharing. We first define a closeness estimation between the user’s itinerary and available drivers. This allows to select a subset of potential drivers. We then compute sets of driving quickest paths, and design a substitution process. Finally, among all admissible solutions, we select the best one based on the earliest arrival time. We provide numerical results using benchmarks based on geographical maps, public transportation timetabling and simulated requests and driving paths. Our numerical experiment shows a running time of a few seconds, suitable for a new real-time transportation application.

We consider a mix transportation problem, which allows to combine a multi-modal public and a ride-sharing transports, in a dynamic environment. The main idea of our approach consists in labelling interesting nodes of a geographical map with information about either riders or drivers, in so-called buckets. Based on the information contained in these buckets, we compute admissible ride-sharing possibilities. To restrict the needed amount of memory, among the different stops along a public transportation path, we only consider the transshipment nodes, where travellers have to make a change between two modes. Each of those stops are potential pick-up or drop-off stops for ride-sharing. We consider a drivers’ maximal waiting time, as well as the maximal driving detour time depending on the actual drive. Each new drive activates a search for new ride-sharing of existing riders. Each new ride activates another process which searches for potential drivers. Among all admissible ride-sharing possibilities, only those which best improve the earliest arrival time are selected. We provide numerical results using real road network of the Lorraine region (FR) and real data provided by a local company. Our numerical experiment shows a running time of a few seconds, suitable for a new real-time transportation application.

Traditional medicine has been used worldwide for centuries to cure or prevent disease and for male or female contraception. Only a few studies have directly investigated the effects of herbal compounds on spermatozoa. In this study, essential oil from Thymus munbyanus was extracted and its effect on human spermatozoa in vitro was analysed. Gas chromatography and Gas chromatography – mass spectrometry analyses identified 64 components, accounting for 98.9% of the composition of the oil. The principal components were thymol (52.0%), γ-terpinene (11.0%), ρ-cymene (8.5%) and carvacrol (5.2%). Freshly ejaculated spermatozoa was exposed from control individuals to various doses of the essential oil for different time periods, and recorded the vitality, the mean motility, the movement characteristics (computer-aided sperm analysis), the morphology and the ability to undergo protein hyperphosphorylation and acrosomal reaction, which constitute two markers of sperm capacitation and fertilizing ability. In vitro , both the essential oil extracted from T. munbyanus and thymol, the principal compound present in this oil, impaired human sperm motility and its capacity to undergo hyperphosphorylation and acrosome reaction. These compounds may, therefore, be of interest in the field of reproductive biology, as potential anti-spermatic agents.

Ridesharing is a mobility concept in which a trip is shared by a vehicle’s driver and one or more passengers called riders. Ridesharing is considered as a more environmentally friendly alternative to single driver commutes in pollution-creating vehicles on overcrowded streets. In this paper, we present the core of a new strategy of the ridesharing system, making it more flexible and competitive than the recurring system. More precisely, we allow the driver and the rider to meet each other at an intermediate starting location and to separate at another intermediate ending location not necessarily their origins and destinations, respectively. This allows to reduce both the driver’s detour and the total travel cost. The term “A priori approach” means that the driver sets the sharing cost rate on the common path with rider in advance. An exact and heuristic approaches to identify meeting locations, while minimizing the total travel cost of both driver and rider are proposed. Finally, we analyze their empirical performance on a set of real road networks consisting of up to 3,5 million nodes and 8,7 million edges. Our experimental results show that our heuristics provide efficient performances within short CPU times and improves the recurring ridesharing approach in terms of cost-savings.

International audience; Several methods can be used to provide water to plants in cropping systems where irrigation is necessary. For instance, drip irrigation has recently received much attention due to its advantages for water conservation. The type of irrigation can also impact the development of several pathogens responsible for soilborne diseases. Here, we studied the effect of drip irrigation and furrow irrigation on the development of grey mould, caused by the airborne fungus Botrytis cinerea, on tomato plants. A field experiment was conducted in 2004 in five unheated greenhouses. Plants were examined individually every 8 days and the proportion of plants attacked by grey mould on leaves, stems or fruits was recorded from the end of March until the end of June. Our results show that the attacks of Botrytis on the stems occurred earlier in furrow irrigation, 98.8 days after planting on average, than in drip irrigation: 106.3 days after planting. The kinetics of plant infection on stems, leaves and fruits were higher under furrow than under drip irrigation. Disease severity was measured by the average number of stem lesions per plant. Disease severity was higher in plants under furrow than under drip irrigation, reaching 1.32 and 0.99, respectively, at the end of June. Plant mortality due to grey mould was first recorded at 94 and 110 days after planting, respectively, in the furrow- and in the drip- irrigated greenhouses. These results suggest that drip irrigation could be a useful tool for the implementation of integrated protection schemes and for reducing the use of pesticides in unheated tomato greenhouses. They may also provide an additional incentive for growers to switch from furrow to drip irrigation in sheltered tomato production

Gray mold, caused by Botrytis cinerea fungus, is a major aerial fungal disease, which affects various important agronomical crops. Phenotypic and genotypic diversity of B. cinerea is very strong and its quick adaptability to selective pressure was reported, which makes the control methods very limited. The objectives of this work aim to study the phenotypic variability exhibited by isolates of B. cinerea in response to high temperatures. This by studying firstly the development of gray mold and temperature fluctuations in commercial tomato greenhouses in the region of Bejaia during two seasons (2012 and 2013), and then, by studying of the effect of temperature on the mycelial growth and spore germination of local isolates. The effect of high temperatures on the development in vitro, aggressiveness on tomato leaflets of B. cinerea isolates collected from different geographical regions (Algeria, France and Norway), as well as the aggressiveness of these isolates on tomato plant in optimal conditions were reported. A final objective aims to study the genotypical variability of B. cinerea populations isolated in tomato greenhouses of Bejaia region. The development of gray mold in tomato greenhouse, despite the high air temperatures recorded inside unheated greenhouse, which is confirmed by the rate of infected plants from the beginning (3.02%) and end of the experiment (25%), respectively. A significant difference was found between local isolates on spore germination and mycelial growth rate differences. Over 90% of the spores were germinated at 21 °C, whereas at 28 °C and 30 °C, spore germination was reduced to less than 79% and 50% respectively after 10 hours. The mycelial growth rate was significantly reduced at 28 °C and 30 °C for all tested isolates. No isolates were developed at 32 °C. The effect of temperature on the aggressiveness of B. cinerea isolates on tomato leaflets and full plants revealed considerable variability between tested isolates. Temperature of 30 °C corresponds to the inhibition of aggressiveness on tomato leaflets. No significant differences in aggressiveness were detected among isolates of B. cinerea collected in Algeria, France and Norway. Finally, a genotypic analysis of 174 isolates using nine microsatellite markers identified four of these isolates as Botrytis pseudocinerea based on the size of the allele at locus Bc6. For all other isolates studied, all loci are polymorphic, with an average number of alleles per locus from 2.77 to 5.22. Considerable genetic variability was detected in all subpopulations (D*>0.87; HNB>0.40). Based on the analysis of the standardized index association, a significant low level of clonality was observed, without excluding the possibility of recombination (rD=0.07, P B. cinerea populations was discussed and should be considered for the management of gray mold., La pourriture grise, causée par le champignon Botrytis cinerea, est l'une des principales maladies fongiques aériennes qui touche diverses cultures d’importance agronomique. La diversité phénotypique et génotypique de B. cinerea est très grande et la capacité d’adaptation de ce champignon à une pression sélective est rapide, ce qui limite considérablement les méthodes de lutte entreprises. Les objectifs de ce travail visent à étudier la variabilité phénotypique montrée par des isolats de B. cinerea en réponse aux températures élevées. Ceci est conduit par l'étude du développement de la pourriture grise et les fluctuations de températures à l’intérieur des serres commerciales de tomates de la région de Bejaia durant deux saisons (2012 et 2013), ainsi que par l'étude de l’effet de la température sur la croissance mycélienne et la germination des spores des isolats locaux. L’effet des températures élevées sur le développement in vitro, l’agressivité sur des folioles de tomate des isolats de B. cinerea isolés dans les différentes régions géographiques (Algérie, France et Norvège), ainsi que l’agressivité de ces isolats sur la plante entière de tomate en conditions optimales sont également abordés. Un dernier objectif vise à étudier la variabilité génotypique des populations de B. cinerea isolés dans les serres de tomates de la région de Bejaia. Le développement de la pourriture grise sous les serres de tomates augmente malgré les températures élevées de l'air à l'intérieur de serre non chauffée, ce qui est confirmé par le taux de plantes infectées depuis le début (3,02%) et la fin de l'expérimentation (25%), respectivement. Des différences significatives sont enregistrées entre les isolats locaux sur la germination des spores, et la vitesse de croissance mycélienne. Plus de 90% des spores sont germées à 21 °C, tandis qu'à 28 °C et 30 °C, la germination des spores a été réduite à moins de 79% et 50% respectivement au bout de 10 heures. La vitesse de croissance mycélienne a été significativement réduite à 28 °C et 30 °C pour tous les isolats testés. Aucun des isolats ne s'est développé à 32 °C. L’effet de la température sur l’agressivité des isolats de B. cinerea sur folioles de tomates et sur les plantes entières a révélé une grande variabilité entre les isolats testés. 30 °C, correspond à la température d’inhibition de l’agressivité sur les folioles de tomate. Aucune différence significative de l’agressivité n’a été détectée entre les isolats de B. cinerea collectés en Algérie, France et Norvège. Enfin, nous avons analysé génotypiquement 174 isolats avec neuf marqueurs microsatellites. Quatre d'entre eux ont été identifiés comme Botrytis pseudocinerea en fonction de la taille de l'allèle au locus Bc6. Pour tous les autres isolats étudiés, tous les loci ont été polymorphes, avec un nombre moyen d'allèles par locus allant de 2,77 à 5,22. Une variabilité génétique considérable a été détectée dans toutes les sous-populations (D*>0,87 ; HNB>0,40). Sur la base de l’analyse de l'indice l'association standardisé, un faible niveau de clonalité a été observé, sans exclure la possibilité d'une recombinaison (rD=0,07, PB. cinerea a été discutée et devrait être pris en considération pour la gestion de la pourriture grise.