Energy efficiency and traffic offloading in wireless mesh networks with delay bounds

In this paper, we study a wireless access network based on the Institute of Electrical and Electronics Engineers 802.11 standard and enriched with features such as caching and mesh networking. This system is analysed in terms of energy efficiency and traffic offloading, two objectives that are somewhat in contrast but both relevant to network and service providers as they directly impact the operational cost. In addition, QoS is also accounted for in the form of guaranteed bandwidth and bounded delay. To this aim, we developed a mathematical model of the system and solved it to optimality by means of integer linear programming. We can thus show how much can be saved both in terms of energy and traffic, also considering various tradeoff points among the two contrasting objectives. As a last step, we provide an investigation on the benefits of adding traffic aggregation features to the mathematical model

The role of grass volatiles on oviposition site selection by Anopheles arabiensis and Anopheles coluzzii

Background: The reproductive success and population dynamics, of Anopheles malaria mosquitoes is strongly influenced by the oviposition site selection of gravid females. Mosquitoes select oviposition sites at different spatial scales, starting with selecting a habitat in which to search. This study utilizes the association of larval abundance in the field with natural breeding habitats, dominated by various types of wild grasses, as a proxy for oviposition site selection by gravid mosquitoes. Moreover, the role of olfactory cues emanating from these habitats in the attraction and oviposition stimulation of females was analysed. Methods: The density of Anopheles larvae in breeding sites associated with Echinochloa pyramidalis, Echinochloa stagnina, Typha latifolia and Cyperus papyrus, was sampled and the larvae identified to species level. Headspace volatile extracts of the grasses were collected and used to assess behavioural attraction and oviposition stimulation of gravid Anopheles arabiensis and Anopheles coluzzii mosquitoes in wind tunnel and two-choice oviposition assays, respectively. The ability of the mosquitoes to differentiate among the grass volatile extracts was tested in multi-choice tent assays. Results: Anopheles arabiensis larvae were the most abundant species found in the various grass-associated habitats. The larval densities described a hierarchical distribution, with Poaceae (Echinochloa pyramidalis and Echinochloa stagnina)-associated habitat sites demonstrating higher densities than that of Typha-associated sites, and where larvae were absent from Cyperus-associated sites. This hierarchy was maintained by gravid An. arabiensis and An. coluzzii mosquitoes in attraction, oviposition and multi-choice assays to grass volatile extracts. Conclusions: The demonstrated hierarchical preference of gravid An. coluzzii and An. arabiensis for grass volatiles indicates that vegetation cues associated with larval habitats are instrumental in the oviposition site choice of the malaria mosquitoes. Identifying volatile cues from grasses that modulate gravid malaria mosquito behaviours has distinct potential for the development of tools to be used in future monitoring and control methods

Violence, Selection and Infant Mortality in Congo

This paper documents the effects of the recent civil war in the Democratic Republic of Congo on mortality both in utero and during the first year of life. It instruments for conflict intensity using a mineral price index, which exploits the exogenous variation in the potential value of mineral resources generated by changes in world mineral prices to predict the geographic distribution of the conflict. Using estimates of civil war exposure on mortality across male and female newborn to assess their relative health, it provides evidence of culling effect (in utero selection) as a consequence of in utero shocks

Dynamique de croissance des bacteries lactiques et modelisation de leur comportement

SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : AR 13861 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Reflexion strategique sur les centres d'appui technique aux industries alimentaires

SIGLEAvailable from INIST (FR), Document Supply Serviceunder shelf-number : RP 14488 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Mise en place d'un centre de transfert en biotechnologie et microbiologie

CNRS AR 11701 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueSIGLEFRFranc

Biotechnologies: etude des reactions et reacteurs biologiques

SIGLECNRS AR 10435 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Production d'ethanol par des bioreacteurs a membranes

SIGLECNRS AR 12450 (1-2) / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc