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C Lemerle

Publications and source records attributed to C Lemerle.

3 recordsLinked to original sources

SmartCell, a framework to simulate cellular processes that combines stochastic approximation with diffusion and localisation: analysis of simple networks.

SmartCell has been developed to be a general framework for modelling and simulation of diffusion-reaction networks in a whole-cell context. It supports localisation and diffusion by using a mesoscopic stochastic reaction model. The SmartCell package can handle any cell geometry, considers different cell compartments, allows localisation of species, supports DNA transcription and translation, membrane diffusion and multistep reactions, as well as cell growth. Moreover, different temporal and spatial constraints can be applied to the model. A GUI interface that facilitates model making is also available. In this work we discuss limitations and advantages arising from the approach used in SmartCell and determine the impact of localisation on the behaviour of simple well-defined networks, previously analysed with differential equations. Our results show that this factor might play an important role in the response of networks and cannot be neglected in cell simulations.

Animals↗

Sodium deficiency of grazing cattle in Papua New Guinea.

Sodium deficiency was suspected from low saliva sodium concentrations in cattle at various sites in the lowlands of Papua New Guinea. In an experiment at Erap, Morobe Province crossbred and pedigree Brahman heifers supplemented with copper, cobalt and/or common salt showed no response to copper or cobalt supplementation. There was a significant growth response (P less than 0.01) to salt supplementation over a 16 week period confirming sodium deficiency in these animals. The response in the crossbreds was twice that in the purebreds. Supplemented crossbred animals grew 0.78 kg/day over the 16 week experimental period.

Animals↗

Assessment of heat stress in dairy cattle in Papua New Guinea.

The effects of breed (Friesian, AIS, Sindi-Sahiwal and Jersey), time of day (am v pm) and season of the year (hot or cool) on rectal temperature, pulse rate and respiratory rate were examined in the Highlands and Lowlands of Papua New Guinea. Two types of variation were investigated. Between-cow variation was the basis for the comparison of sites, seasons and breeds. Between-day variation was used to assess the effect of environmental temperatures on the animal parameters. Respiration rate and rectal temperature appeared more sensitive as indicators of heat stress than pulse rate and using these criteria the highlands climate was suitable for dairy cattle. Jerseys and Sahiwals showed lower respiratory rates compared with Friesians and AIS and their increase in rectal temperature during the day was less than the other two breeds but was not significantly so. The relationships between respiration rate and rectal temperature are discussed.

Animals↗