An investigation of selected soil properties influencing the management and playability of New Zealand cricket pitches : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science in soil science, Massey University

The 1980's has been a period of growth for New Zealand cricket. The advent of the one day game plus international success has developed spectator interest and support to an unprecedented level. Cricket is certainly one game where player performance is very much dependent on the surface provided. It is perhaps fair to say that the standard of many New Zealand first class pitches has not allowed the development of entertaining cricket. As a result, pitches have been the target of increasing criticism from spectators, administrators, and players 'alike. Cricket pitch preparation has been said to be an 'art'. But the groundsman has limited scope to practice the art if the suitability of the soil used for pitch preparation is wanting. In an attempt to gain an understanding of the contribution of soil properties to good pitch preparation, the New Zealand Cricket Council and Soil Bureau of the Department of Scientific and Industrial Research (DSIR) provided funding for a research programme. It was hoped that improved playability and pitch performance could be achieved by combining the 'art' of pitch preparation with sound scientific principles. The objectives of the research programme were: 1. To develop and standardise a set of laboratory procedures aimed at selecting soils and characterizing their suitability for cricket pitches. 2. To establish a comprehensive inventory of physical and chemical soil properties for a number of current pitch soils which can be used as a reference for selection of new pitch soils. 3. To relate sound scientific principles to field management techniques and pitch performance in an attempt to assist the groundsman with pitch preparation. 4. To investigate the contributions of playability, and their interactions with soil properties. 5. To elucidate the value of the nuclear moisture-density method for in situ measurement of pitch soil water content and bulk density. 6. To develop and implement a soil monitoring system for groundsmen who can then use it to evaluate changes in soil properties during pitch preparation. This would allow the development of specific management programmes for individual venues. 7. To suggest areas for future research. To meet these objectives a preliminary study (Cameron-Lee, 1984) was carried out to identify three soil parameters, namely clay content, clay type, and pitch soil profile, which affect pitch performance. An expansion of the findings of the preliminary study form the basis of this research programme. This investigation incorporated a field trial using four soils commonly known as the Palmerston North1 , St John, Ward, and Kakanui. The soils have different chemical and physical properties. They are all currently in use throughout New Zealand on first class pitches. In addition, three pitch soils, namely the Marton, Redhill and Naike were evaluated, along with the field trial soils in the laboratory to provide a greater comparative analysis of pitch soil properties

Voluntary activation of human knee extensors measured using transcranial magnetic stimulation

The aim of this study was to determine the applicability and reliability of a transcranial magnetic stimulation twitch interpolation technique for measuring voluntary activation of a lower limb muscle group. Cortical voluntary activation of the knee extensors was determined in nine healthy men on two separate visits by measuring superimposed twitch torques evoked by transcranial magnetic stimulation during isometric knee extensions of varying intensity. Superimposed twitch amplitude decreased linearly with increasing voluntary torque between 50 and 100% of mean maximal torque, allowing estimation of resting twitch amplitude and subsequent calculation of voluntary activation. There were no systematic differences for maximal voluntary activation within day (mean ± S.D. 90.9 ± 6.2 versus 90.7 ± 5.9%; P = 0.98) or between days (90.8 ± 6.0 versus 91.2 ± 5.7%; P = 0.92). Systematic bias and random error components of the 95% limits of agreement were 0.23 and 9.3% within day versus −0.38 and 7.5% between days. Voluntary activation was also determined immediately after a 2 min maximal voluntary isometric contraction; in four of these subjects, voluntary activation was determined 30 min after the sustained contraction. Immediately after the sustained isometric contraction, maximal voluntary activation was reduced from 91.2 ± 5.7 to 74.2 ± 12.0% (P < 0.001), indicating supraspinal fatigue. After 30 min, voluntary activation had recovered to 85.4 ± 8.8% (P = 0.39 versus baseline). These results demonstrate that transcranial magnetic stimulation enables reliable measurement of maximal voluntary activation and assessment of supraspinal fatigue of the knee extensors

The integration of geometric information within design and manufacture

Imperial Users onl

The nakhlite meteorites provide evidence for mineralization of martian CO2 by carbonation of silicates

Evidence from the Lafayette meteorite shows that carbon dioxide could have been sequestered very effectively from the martian atmosphere by mineral carbonation

Engineering of GlcNAc-1-phosphotransferase for production of highly phosphorylated lysosomal enzymes for enzyme replacement therapy

Several lysosomal enzymes currently used for enzyme replacement therapy in patients with lysosomal storage diseases contain very low levels of mannose 6-phosphate, limiting their uptake via mannose 6-phosphate receptors on the surface of the deficient cells. These enzymes are produced at high levels by mammalian cells and depend on endogenous GlcNAc-1-phosphotransferase α/β precursor to phosphorylate the mannose residues on their glycan chains. We show that co-expression of an engineered truncated GlcNAc-1-phosphotransferase α/β precursor and the lysosomal enzyme of interest in the producing cells resulted in markedly increased phosphorylation and cellular uptake of the secreted lysosomal enzyme. This method also results in the production of highly phosphorylated acid β-glucocerebrosidase, a lysosomal enzyme that normally has just trace amounts of this modification