A comparison of the cuticular properties of argasid and ixodid ticks: Ornithodoros moubata (Argasidae) vs. Amblyomma hebraeum and Ixodes pacificus (Ixodidae).

Ticks (Chelicerata, Ixodida) are blood-feeding ectoparasites believed to have evolved at least about 120 millions of years ago and found worldwide. However, many aspects of their unique life cycle and anatomy, including their mechanical properties, remain to be understood. Here, we compared the mechanical properties of the cuticle of the argasid tick Ornithodoros moubata to those of two species of ixodid tick, Amblyomma hebraeum and Ixodes pacificus that we explored in our earlier studies of the tick exoskeleton.

A comparison of the cuticular properties of the female ticks Ixodes pacificus and Amblyomma hebraeum (Acari: Ixodidae) throughout the feeding period.

The mechanical properties of the cuticle of Ixodes pacificus (Ip) are compared to those of Amblyomma hebraeum (Ah) from our earlier work. The 10-fold size difference between the species is expected to lead to significant differences in mechanical properties, because cuticular stretch depends on high internal hydrostatic pressure during the rapid phase of engorgement. We demonstrate here: (1) The cuticle of partially fed Ip is less stiff and viscous than that of Ah.

Cuticle expansion during feeding in the tick Amblyomma hebraeum (Acari: Ixodidae): The role of hydrostatic pressure.

Female Amblyomma hebraeum ticks (Acari: Ixodidae) increase their weight ∼10-fold during a 'slow phase of engorgement' (7-9 days), and a further 10-fold during the 'rapid phase' (12-24h). During the rapid phase, the cuticle thins by half, with a plastic (permanent) deformation of greater than 40% in two orthogonal directions. A stress of 2.

Mechanical properties of the cuticle of the tick Amblyomma hebraeum (Acari: Ixodidae).

Female ticks of the family Ixodidae increase their mass up to 100-fold during the 7-10 day feeding period. We determined the material properties of the alloscutal cuticle of female Amblyomma hebraeum from the time of moulting through to full engorgement. The material properties of the cuticle were evaluated by a Kelvin-Voigt analysis of compliance determined from the stretch of loops of cuticle under stress.

Female ixodid ticks grow endocuticle during the rapid phase of engorgement.

Lees (Proc Zool Soc Lond 121:759-772, 1952) concluded that the ixodid tick Ixodes ricinus grows endocuticle during the slow but not during the rapid, phase of engorgement, a conclusion supported by Andersen and Roepstorff (Insect Biochem Mol Biol 35:1181-1188, 2005) for the same species. In this study analysis of dimensional data and cuticle weight measurements from female ixodid ticks (Amblyomma hebraeum) were used to test this hypothesis. Both approaches showed that endocuticle growth continues during the rapid phase, tapering to zero at a fed/unfed weight ratio of ~60.

Cuticular plasticization in the tick, Amblyomma hebraeum (Acari: Ixodidae): possible roles of monoamines and cuticular pH.

The degree of plasticization of the alloscutal cuticle of a 'hard' (ixodid) tick, Amblyomma hebraeum, and a 'soft' (argasid) tick, Ornithodoros moubata, was assessed throughout the blood-feeding period. Cuticle viscosity was calculated from rate of creep of cuticle under constant load using a Maxwell model. Feeding-related plasticization (i.

Optimizing the logistics of anaerobic digestion of manure.

Electrical power production from the combustion of biogas from anaerobic digestion (AD) of manure is a means of recovering energy from animal waste. We evaluate the lowest cost method of moving material to and from centralized AD plants serving multiple confined feeding operations. Two areas are modeled, Lethbridge County, Alberta, Canada, an area of concentrated beef cattle feedlots, and Red Deer County, Alberta, a mixed-farming area with hog, dairy, chicken and beef cattle farms, and feedlots.

Rail vs truck transport of biomass.

This study analyzes the economics of transshipping biomass from truck to train in a North American setting. Transshipment will only be economic when the cost per unit distance of a second transportation mode is less than the original mode. There is an optimum number of transshipment terminals which is related to biomass yield.

Development of a multicriteria assessment model for ranking biomass feedstock collection and transportation systems.

This study details multicriteria assessment methodology that integrates economic, social, environmental, and technical factors in order to rank alternatives for biomass collection and transportation systems. Ranking of biomass collection systems is based on cost of delivered biomass, quality of biomass supplied, emissions during collection, energy input to the chain operations, and maturity of supply system technologies. The assessment methodology is used to evaluate alternatives for collecting 1.

Large-scale ethanol fermentation through pipeline delivery of biomass.

Issues of traffic congestion and community acceptance limit the size of biomass-processing plants based on truck delivery to about 2 million (M) dry t/yr or less. In this study, the cost of ethanol from an ethanol fermentation plant processing 2 M dry t/yr of corn stover supplied by truck is compared with that of larger plants in the range of 4-38 M dry t/yr supplied by a combination of trucks plus pipelines. For corn stover, a biomass source with a low yield per gross hectare, the cost of ethanol from larger plants is always higher.

Pipeline transport and simultaneous saccharification of corn stover.

Pipeline transport of corn stover delivered by truck from the field is evaluated against a range of truck transport costs. Corn stover transported by pipeline at 20% solids concentration (wet basis) or higher could directly enter an ethanol fermentation plant, and hence the investment in the pipeline inlet end processing facilities displaces comparable investment in the plant. At 20% solids, pipeline transport of corn stover costs less than trucking at capacities in excess of 1.

Pipeline transport of biomass.

The cost of transporting wood chips by truck and by pipeline as a water slurry was determined. In a practical application of field delivery by truck of biomass to a pipeline inlet, the pipeline will only be economical at large capacity ( >0.5 million dry t/yr for a one-way pipeline, and >1.