Search results for "Mio"
showing 10 items of 7243 documents
Environmental change and disease dynamics: effects of intensive forest management on Puumala hantavirus infection in boreal bank vole populations.
2012
Intensive management of Fennoscandian forests has led to a mosaic of woodlands in different stages of maturity. The main rodent host of the zoonotic Puumala hantavirus (PUUV) is the bank vole (Myodes glareolus), a species that can be found in all woodlands and especially mature forests. We investigated the influence of forest age structure on PUUV infection dynamics in bank voles. Over four years, we trapped small mammals twice a year in a forest network of different succession stages in Northern Finland. Our study sites represented four forest age classes from young (4 to 30 years) to mature (over 100 years) forests. We show that PUUV-infected bank voles occurred commonly in all forest age…
Burial behaviour by dealates of the termite Pseudacanthotermes spiniger (Termitidae, Macrotermitinae) induced by chemical signals from termite corpses
2011
In order to maintain healthy colonies, termite workers dispose of the cadavers of dead nest mates by cannibalism, burial, or necrophoresis. However, when multiple reproductives found a new colony by pleometrosis, there are no worker castes at the early stages of the foundation to eliminate or isolate the corpses. In this study, we showed that in young pleometrotic colonies, reproductives of Pseudacanthotermes spiniger had the ability to perform this task. Because of the claustral conditions, and the potential inability of the dealates to feed on their own, their behaviour was restricted to the burial of the cadaver within the initial chamber. This burial behaviour, previously not reported i…
Parasite and host assemblages: embracing the reality will improve our knowledge of parasite transmission and virulence.
2010
10 pages; International audience; Interactions involving several parasite species (multi-parasitized hosts) or several host species (multi-host parasites) are the rule in nature. Only a few studies have investigated these realistic, but complex, situations from an evolutionary perspective. Consequently, their impact on the evolution of parasite virulence and transmission remains poorly understood. The mechanisms by which multiple infections may influence virulence and transmission include the dynamics of intrahost competition, mediation by the host immune system and an increase in parasite genetic recombination. Theoretical investigations have yet to be conducted to determine which of these…
An invasive insect herbivore disrupts plant volatile-mediated tritrophic signalling
2017
Plants respond to insect attack by emission of volatile organic compounds, which recruit natural enemies of the attacking herbivore, constituting an indirect plant defence strategy. In this context, the egg parasitoid Trissolcus basalis is attracted by oviposition-induced plant volatiles emitted by Vicia faba plants as a consequence of feeding and oviposition by the pentatomid host Nezara viridula. However, this local tritrophic web could be affected by the recent invasion by the alien pentatomid bug Halyomorpha halys, an herbivore that shares the same environments as native pentatomid pests. Therefore, we investigated in laboratory conditions the possible impact of H. halys on the plant vo…
Behavioral responses of Hyalesthes obsoletus to host-plant volatiles cues
2016
The polyphagous planthopper Hyalesthes obsoletus Signoret is considered to be the principal vector of stolbur phytoplasma, which is associated with yellow diseases of grapevine. To explore the possibility of developing novel control strategies, the behavioral responses to six synthetic mixtures and nine single compounds, previously identified from the headspace of Vitex agnus-castus L. (chaste tree) and Urtica dioica L. (nettle), were investigated in Y-tube bioassays. Choice tests revealed differences in the behavioral responses of males and females to the volatiles that they were exposed to. Males were attracted to a mixture containing (E)-β-caryophyllene, 1,8-cineole, (E,E)-α-farnesene, (…
Semiochemical exploitation of host-associated cues by seven Melittobia parasitoid species : Behavioral and phylogenetic implications
2018
Chemical compounds (infochemicals or semiochemicals) play an important role both in intra-specific and inter-specific communication. For example, chemical cues appear to play a key role in the host selection process adopted by insect parasitoids. In recent years significant advances have been made in order to understand the chemical ecology of insect parasitoids. However, little information is available about the evolution of semiochemical use in the host location process of insect parasitoids. Here we investigated the strategy adopted by seven closely related parasitoid species in the genus Melittobia when foraging for four different suitable hosts. By using an integrated approach that com…
Identification and biological traits of a planthopper from the genus Pentastiridius (Hemiptera: Cixiidae) adapted to an annual cropping rotation
2009
International audience; Cixiid planthoppers have been shown to vector phloem-limited prokaryotes associated with plant diseases world-wide. In eastern France, an emerging disease of sugar beet called syndrome basses richesses has been associated with phloem-restricted bacteria transmitted by a cixiid planthopper within the genus Pentastiridius. Early investigation suggested the species being Pentastiridius beieri. On the basis of a morphological and phylogenetic study we report the identification of the planthopper as Pentastiridius leporinus. Furthermore we report some biological traits of the species, which shows a surprising ecological adaptation to an annual cropping rotation sugar beet…
Escala de percepción ante crisis y pandemias : desarrollo y validación de una escala pedagógica
2021
Objetivos: Abordar la metodología de estudio con respecto a epidemia/pandemia requiere involucrar pensamiento complejo frente a los retos que denota esta situación. El objetivo de este estudio es validar un cuestionario de percepción y creencias dirigido a estudiantes de medicina y enfermería sobre el uso del cine ante la complejidad de un evento pandémico, con el propósito de potenciar las estrategias de enseñanza. Metodología: Se encuestó a 131 estudiantes. La evaluación de la confiabilidad se realizó a través del análisis de consistencia interna. La valoración de los 19 ítems se evaluó mediante análisis de correlación de Pearson y la validez de constructo mediante análisis factorial expl…
Évaluation de la qualité métrologique des données du programme de médicalisation du système d’information (PMSI) en périnatalité : étude pilote réali…
2015
Resume Position du probleme La France est l’un des derniers pays europeens a ne pas pouvoir fournir d’informations perinatales fiables, indispensables a la realisation de travaux de recherche et a la production d’indicateurs nationaux. Le systeme d’information perinatale en France est fragmente et les donnees, difficiles a regrouper, ne repondent pas aux exigences d’Europeristat. Les donnees du PMSI offrent la potentialite de fournir des informations systematiques et standardisees pour l’ensemble des naissances. L’objectif etait d’etudier la qualite metrologique des donnees du PMSI pour construire des indicateurs de base en sante perinatale dans trois centres hospitaliers universitaires, av…
Analyse de l’impact des facteurs socioéconomiques sur la sévérité initiale des accidents vasculaires cérébraux en France métropolitaine et aux Antill…
2016
Introduction Malgre un systeme de sante tres favorable, les inegalites sociales de sante se sont creusees en France au cours des deux dernieres decennies. En depit de cette situation, l’impact des facteurs socioeconomiques a ete peu etudie a l’echelle individuelle sur le territoire francais et les donnees a meme de mobiliser les acteurs restent insuffisantes. Par ailleurs le retentissement des AVC sur l’etat de sante des francais est considerable : premiere cause de handicap de l’adulte, deuxieme cause de demence, troisieme cause de mortalite. De plus, le niveau socioeconomique, par son impact sur les facteurs de risque d’AVC, est susceptible d’affecter les manifestations cliniques initiale…