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Muscles of individuals with a spinal cord injury (SCI) exhibit an unexpected leftward shift in the force (torque)-frequency relationship. We investigated whether differences in torque-angle relationships between SCI and able-bodied control muscles could explain this shift. Electrically stimulated knee-extensor contractions were obtained at knee flexion angles of between 30° and 90°. Torque-frequency relationships were obtained at 30°, 90°, and optimum angle. Optimum angle was not different between groups but SCI-normalized torques were lower at the extreme angles. At all angles, SCI muscles produced higher relative torques at low stimulation frequencies. Thus, there was no evidence of a consistent change in the length of paralyzed SCI muscles, and the anomalous leftward shift in the torque-frequency relationship was not the result of testing the muscle at a relatively long length. The results provide valuable information about muscle changes occurring in various neurological disorders. © 2005 Wiley Periodicals, Inc.

The I-3 gene from the wild tomato species Lycopersicon pennellii confers resistance to race 3 of the devastating vascular wilt pathogen Fusarium oxysporum f. sp. lycopersici. As an initial step in a positional cloning strategy for the isolation of I-3, we converted restriction fragment length polymorphism and conserved orthologue set markers, known genes and a resistance gene analogue (RGA) mapping to the I-3 region into PCR-based sequence characterised amplified region (SCAR) and cleaved amplified polymorphic sequence (CAPS) markers. Additional PCR-based markers in the I-3 region were generated using the randomly amplified DNA fingerprinting (RAF) technique. SCAR, CAPS and RAF markers were used for high-resolution mapping around the I-3 locus. The I-3 gene was localised to a 0.3-cM region containing a RAF marker, eO6, and an RGA, RGA332. RGA332 was cloned and found to correspond to a putative pseudogene with at least two loss-of-function mutations. The predicted pseudogene belongs to the Toll interleukin-1 receptor-nucleotide-binding site-leucine-rich-repeat sub-class of plant disease resistance genes. Despite the presence of two RGA332 homologues in L. esculentum, DNA gel blot and PCR analysis suggests that no other homologues are present in lines carrying I-3 that could be alternative candidates for the gene.

Effects of two different training regimens on the contractile properties of the quadriceps muscle were studied in six individuals with spinal cord injury. Each subject had both limbs trained with the two regimens, consisting of stimulation with low frequencies (LF) at 10 Hz or high frequencies (HF) at 50 Hz; one limb of each subject was stimulated with the LF protocol and the other with the HF regimen. Twelve weeks of daily training increased tetanic tension by ∼20%, which was not significantly different between training regimens. Interestingly, after HF but not LF training, the unusual high forces at the low frequency range of the force-frequency relationship decreased, possibly due to a reduced activation per impulse. After LF but not HF training, force oscillation amplitudes declined (by 33%) as relaxation tended to slow, which may have opposed possible effects of reduced activation as seen after HF training. Finally, fatigue resistance also increased rapidly after LF training (by 43%) but not after HF training. These results indicate that different types of training may selectively change different aspects of function in disused muscles. © 2002 Wiley Periodicals, Inc.

1. The effects of single isovelocity shortening contractions on force production of the electrically stimulated human adductor pollicis muscle were investigated in seven healthy male subjects. 2. Redeveloped isometric force immediately following isovelocity shortening was always depressed compared with the isometric force recorded at the same muscle length but without preceding shortening. The maximal isometric force deficit (FD) was (mean ± S.E.M.) 37 ± 2% after 38 deg of shortening at 6.1 degs

Climate change is an important global issue but is yet to be recognised as such by many rangelands users. This paper reviews some of the uncertainties relating to pre-instrumental and future climate change and documents current trends and fluctuations in climate of Queensland's grazing lands. Analysis of daily climate surfaces for Queensland's pastoral/cropping zone shows high variability in annual rainfall which is influenced by the El NiHo-Southern Oscillation (ENSO) phenomenon. This relationship, when examined using moving windows, has changed during this century with the 1930-40s being a period of low correlation. Minimum temperatures taken from the climate surfaces also changed, showing a significant (P<0.01) increase over time especially in May. Over the 40 years since 1957, annual minimum temperatures have increased by l.0°C for the pastoral/cropping zone and coastal sub-zone, winter minimum temperatures by 1.2°C for the pastoral/cropping zone (1.3°C for the coastal sub-zone), summer minimum temperatures by 0.7°C for the pastoral/cropping zone and coastal sub-zone, and May minimum temperatures by 2.8°C for the pastoral/cropping zone (3.0°C for the coastal sub-zone). Consistent significant trends in vapour pressure (increasing, P<0.001) and solar radiation (decreasing, P<0.05) also occurred in May. The mechanisms for the identified climate trends and unusual behaviour of ENS0 are the subject of speculation with attribution of causes to natural variability or the enhanced greenhouse effect being unresolved. Continued monitoring of these trends and fluctuations will be important for the future management of Queensland's grazing lands with this analysis highlighting the need for discrimination of trends from natural variability. In terms of grazing management and degradation processes, this work also highlights that general changes in climate averages may disguise important variation at yearly and decadal time scales.

Mine closure plans in Nevada must be submitted two years before anticipated closure of the mine or specific mine component (such as heap leached ore, tailings impoundment, waste rock dump or pit lake). Upon termination of a component's active use it must be sampled, characterised for possible sources of water pollution and stabilised. Spent ore must be rinsed until the cyanide level in rinse effluent is less than 0.2 mg/l and the remaining solids, depending on potential contaminants, left or buried in place. Tailings stabilisation must ensure that migration of any potential contaminant within the tailings is inhibited, and additional surface amendment and/or burial must be undertaken to promote runoff and eliminate infiltration of meteoric water. Waste rock and overburden dumps are also possible sources of groundwater contamination and must be isolated or encapsulated. It must be ensured that disused open pits cannot become impoundments with the potential to adversely affect the environment. Following closure and stabilisation, post-closure monitoring is required for between 5 and 30 years., Mine closure plans in Nevada must be submitted two years before anticipated closure of the mine or specific mine component (such as heap leached ore, tailings impoundment, waste rock dump or pit lake). Upon termination of a component's active use it must be sampled, characterised for possible sources of water pollution and stabilised. Spent ore must be rinsed until the cyanide level in rinse effluent is less than 0.2 mg/l and the remaining solids, depending on potential contaminants, left or buried in place. Tailings stabilisation must ensure that migration of any potential contaminant within the tailings is inhibited, and additional surface amendment and/or burial must be undertaken to promote runoff and eliminate infiltration of meteoric water. Waste rock and overburden dumps are also possible sources of groundwater contamination and must be isolated or encapsulated. It must be ensured that disused open pits cannot become impoundments with the potential to adversely affect the environment. Following closure and stabilisation, post-closure monitoring is required for between 5 and 30 years.