title: Effect of footwear and overhead goal on the Landing Error Scoring System

authors: Boswell-Smith, Caleb

subjects: Anterior Cruciate Ligament

abstract: A large proportion of the population undertakes sport and exercise either for recreation or competition. However, with increased participation in sport and exercise, the occurrence of sport-related injuries also increases. Anterior Cruciate Ligament (ACL) injuries are injuries to the knee and one of the most common injuries in a sporting environment that occur from noncontact mechanisms. The Landing Error Scoring System (LESS) is a common screening tool used to identify individuals who are more at risk of sustaining an ACL injury based on double-leg jump-landing (DLJL) kinematics. Despite the LESS demonstrating good-toexcellent reliability and predictive value, the LESS is sensitive to various factors (e.g., protocol alterations) and has been criticised for lacking sport specificity. Despite studies conducting the LESS both with and without footwear and using an overhead goal during jumping tasks to increase sport specificity, to date, there is no research comparing LESS outcomes based on the presence/absence of footwear or presence/absence of an overhead goal.
Chapter One summarises literature surrounding sports injuries, ACL injuries, injury aetiology, injury prevention models, and injury risk screening tools used in sports with a focus on the LESS. Footwear and cueing in sports are also addressed. Chapter Two is experimental and compares overall LESS scores, group- and individual-level injury risk categorisation, specific LESS errors, and jump heights between footwear and no footwear conditions. Chapter Three is experimental and compares these same outcome measures between overhead goal and no goal conditions. Chapter Four summarises the key findings from the two experimental chapters, and addresses the limitations, strengths, and future research directions arising from this Thesis.
In Chapter Two, 80 participants (55% male) performed a DLJL task where they landed from a 30-cm high box to 50% of their own body height and immediately jumped vertically for maximum height for LESS assessment. Participants completed three trials under two randomordered conditions: with and without footwear. Group mean LESS scores were greater (0.3 errors, p = 0.022) and jump heights were lower (0.6 cm, p = 0.029) in the footwear than barefoot condition, but differences were trivial and not clinically meaningful. Although the number of high-risk participants was comparable between groups (p = 1.000), categorisation was inconsistent for 16.25% of individuals and the occurrence of four of the 17 specific landing errors significantly differed between conditions. Based on the study findings, footwear does not appear to meaningfully influence mean LESS scores, risk categorisation, or jump height at a group level. At an individual level, footwear can affect risk categorisation and landing strategies. Hence, use of a consistent protocol is recommended in clinical setting, and use of footwear is advised for assessing injury risk given the predictive value of the LESS barefoot is unknown.
In Chapter Three, 76 participants (51% male) performed a DLJL task where they landed from a 30-cm high box to 50% of their own body height and immediately jumped vertically for maximum height for LESS assessment. Participants completed three trials under two randomordered conditions: with and without an overhead goal. Mean LESS scores were greater (0.3 errors, p < 0.001) with the overhead goal, but this small difference was not clinically meaningful. Similarly, although the number of high-risk participants was significantly greater with the overhead goal (p = 0.039), the 9.2% difference was trivial. Participants jumped 2.7 cm higher with the overhead goal (p < 0.001) without affecting the occurrence of any specific LESS errors. Based on the results found, performing the LESS with an overhead goal enhances sport specificity and elicits greater vertical jump performances with minimal change in landing errors and risk categorisation. Adding an overhead goal to LESS might enhance its suitability for injury risk screening, although the predictive value of LESS with an overhead goal needs confirmation.

text: Effect of footwear and overhead goal on the Landing Error Scoring System A large proportion of the population undertakes sport and exercise either for recreation or competition. However, with increased participation in sport and exercise, the occurrence of sport-related injuries also increases. Anterior Cruciate Ligament (ACL) injuries are injuries to the knee and one of the most common injuries in a sporting environment that occur from noncontact mechanisms. The Landing Error Scoring System (LESS) is a common screening tool used to identify individuals who are more at risk of sustaining an ACL injury based on double-leg jump-landing (DLJL) kinematics. Despite the LESS demonstrating good-toexcellent reliability and predictive value, the LESS is sensitive to various factors (e.g., protocol alterations) and has been criticised for lacking sport specificity. Despite studies conducting the LESS both with and without footwear and using an overhead goal during jumping tasks to increase sport specificity, to date, there is no research comparing LESS outcomes based on the presence/absence of footwear or presence/absence of an overhead goal.
Chapter One summarises literature surrounding sports injuries, ACL injuries, injury aetiology, injury prevention models, and injury risk screening tools used in sports with a focus on the LESS. Footwear and cueing in sports are also addressed. Chapter Two is experimental and compares overall LESS scores, group- and individual-level injury risk categorisation, specific LESS errors, and jump heights between footwear and no footwear conditions. Chapter Three is experimental and compares these same outcome measures between overhead goal and no goal conditions. Chapter Four summarises the key findings from the two experimental chapters, and addresses the limitations, strengths, and future research directions arising from this Thesis.
In Chapter Two, 80 participants (55% male) performed a DLJL task where they landed from a 30-cm high box to 50% of their own body height and immediately jumped vertically for maximum height for LESS assessment. Participants completed three trials under two randomordered conditions: with and without footwear. Group mean LESS scores were greater (0.3 errors, p = 0.022) and jump heights were lower (0.6 cm, p = 0.029) in the footwear than barefoot condition, but differences were trivial and not clinically meaningful. Although the number of high-risk participants was comparable between groups (p = 1.000), categorisation was inconsistent for 16.25% of individuals and the occurrence of four of the 17 specific landing errors significantly differed between conditions. Based on the study findings, footwear does not appear to meaningfully influence mean LESS scores, risk categorisation, or jump height at a group level. At an individual level, footwear can affect risk categorisation and landing strategies. Hence, use of a consistent protocol is recommended in clinical setting, and use of footwear is advised for assessing injury risk given the predictive value of the LESS barefoot is unknown.
In Chapter Three, 76 participants (51% male) performed a DLJL task where they landed from a 30-cm high box to 50% of their own body height and immediately jumped vertically for maximum height for LESS assessment. Participants completed three trials under two randomordered conditions: with and without an overhead goal. Mean LESS scores were greater (0.3 errors, p < 0.001) with the overhead goal, but this small difference was not clinically meaningful. Similarly, although the number of high-risk participants was significantly greater with the overhead goal (p = 0.039), the 9.2% difference was trivial. Participants jumped 2.7 cm higher with the overhead goal (p < 0.001) without affecting the occurrence of any specific LESS errors. Based on the results found, performing the LESS with an overhead goal enhances sport specificity and elicits greater vertical jump performances with minimal change in landing errors and risk categorisation. Adding an overhead goal to LESS might enhance its suitability for injury risk screening, although the predictive value of LESS with an overhead goal needs confirmation.

year: 2022

title: Cellulases from extremely thermophilic anaerobic bacteria: a comparison of several new cellulolytic isolates and the partial purification and characterisation of components of the cellulase complex from one isolate

authors: Sharrock, Keith R.

abstract: Forty-seven thermal pool sites in the central volcanic plateau of the North Island of New Zealand were sampled and enrichment cultures on crystalline cellulose screened for growth and cellulase activity. Eight anaerobic cellulolytic cultures resulted. Cellulolytic isolates were obtained from five of these cultures. All were obligate anaerobic non-sporing rods, staining Gram-negative. Most grew well at 75°C but none grew at 80°C. CMCase activity from some isolates exhibited exceptional thermal stability, with half-lives at 85°C in excess of 10 hours. Isolates from two sources, designated TP8 and TP10, were capable of completely hydrolysing crystalline cellulose and accumulated reducing sugar and avicelase activity in the growth medium. Levels of CMCase and avicelase in our most active culture supernatants were between 10 and 35% of those of Clostridium thermocellum grown on the same medium (but at 60°C). All produced acetic acid and ethanol in varying proportions, with a consequent tendency to decrease the pH of the growth medium. Cellobiose at 0.2%(w/v) repressed production of CMCase activity by most of the isolates by about 50%, but led to a slightly increased CMCase production by two of them.
One of the isolates capable of completely hydrolysing crystalline cellulose (TP8.T6.3.3.1) was subjected to repeated subculture, reselection and reisolation to ensure its purity. The cell-free cellulase complex of this organism was found to produce partial solubilisation of a range of natural cellulosics, and also contained β-glucosidase activity.
Ammonium sulphate precipation and adsorption onto crystalline cellulose were the best of the methods tested for concentrating the low levels of cellulolytic activity in the culture supernatant of TP8.T6.3.3.1. Adsorption onto cellulose was the cheapest alternative and also doubled as a preliminary fractionation and purification step.
Three fractions, separated on the basis of their affinities for crystalline cellulose, were found to interact synergistically in hydrolysing crystalline cellulose when recombined.
 Conventional ion exchange and gel permeation column chromatography served only to subdivide the TP8.T6.3.3.1 cellulase complex into subcomplexes. These were fractionated further using preparative SDS-PAGE and IEF. The cellulose-binding component of the cellulase complex was found to contain an unexpectedly large number of active components (20 being a conservative estimate). Several of these component proteins exhibited clear differences in relative reactivities towards a range of cellulosic substrates. When rerun on SDS-PAGE, almost all produced single protein bands with mobilities indicative of molecular weights covering the range 20,000 to 140,000. Isoelectric points were all in the range pH 4.5-5.0. However, narrow range isoelectric focussing (pH 4.5-5.0) produced further subdivision of these single bands. The bands produced by isoelectric focussing (7-10 per SDS-PAGE band) each bore a share of the endoglucanase activity. We were unable to individually characterize the component activities at this level, and it was not clear whether these multiple components were artefacts of the isoelectric focussing, distinct products of multiple genes, modified products of a relatively small number of genes or microheterogeneity due to ageing of the proteins.

text: Cellulases from extremely thermophilic anaerobic bacteria: a comparison of several new cellulolytic isolates and the partial purification and characterisation of components of the cellulase complex from one isolate Forty-seven thermal pool sites in the central volcanic plateau of the North Island of New Zealand were sampled and enrichment cultures on crystalline cellulose screened for growth and cellulase activity. Eight anaerobic cellulolytic cultures resulted. Cellulolytic isolates were obtained from five of these cultures. All were obligate anaerobic non-sporing rods, staining Gram-negative. Most grew well at 75°C but none grew at 80°C. CMCase activity from some isolates exhibited exceptional thermal stability, with half-lives at 85°C in excess of 10 hours. Isolates from two sources, designated TP8 and TP10, were capable of completely hydrolysing crystalline cellulose and accumulated reducing sugar and avicelase activity in the growth medium. Levels of CMCase and avicelase in our most active culture supernatants were between 10 and 35% of those of Clostridium thermocellum grown on the same medium (but at 60°C). All produced acetic acid and ethanol in varying proportions, with a consequent tendency to decrease the pH of the growth medium. Cellobiose at 0.2%(w/v) repressed production of CMCase activity by most of the isolates by about 50%, but led to a slightly increased CMCase production by two of them.
One of the isolates capable of completely hydrolysing crystalline cellulose (TP8.T6.3.3.1) was subjected to repeated subculture, reselection and reisolation to ensure its purity. The cell-free cellulase complex of this organism was found to produce partial solubilisation of a range of natural cellulosics, and also contained β-glucosidase activity.
Ammonium sulphate precipation and adsorption onto crystalline cellulose were the best of the methods tested for concentrating the low levels of cellulolytic activity in the culture supernatant of TP8.T6.3.3.1. Adsorption onto cellulose was the cheapest alternative and also doubled as a preliminary fractionation and purification step.
Three fractions, separated on the basis of their affinities for crystalline cellulose, were found to interact synergistically in hydrolysing crystalline cellulose when recombined.
 Conventional ion exchange and gel permeation column chromatography served only to subdivide the TP8.T6.3.3.1 cellulase complex into subcomplexes. These were fractionated further using preparative SDS-PAGE and IEF. The cellulose-binding component of the cellulase complex was found to contain an unexpectedly large number of active components (20 being a conservative estimate). Several of these component proteins exhibited clear differences in relative reactivities towards a range of cellulosic substrates. When rerun on SDS-PAGE, almost all produced single protein bands with mobilities indicative of molecular weights covering the range 20,000 to 140,000. Isoelectric points were all in the range pH 4.5-5.0. However, narrow range isoelectric focussing (pH 4.5-5.0) produced further subdivision of these single bands. The bands produced by isoelectric focussing (7-10 per SDS-PAGE band) each bore a share of the endoglucanase activity. We were unable to individually characterize the component activities at this level, and it was not clear whether these multiple components were artefacts of the isoelectric focussing, distinct products of multiple genes, modified products of a relatively small number of genes or microheterogeneity due to ageing of the proteins.

year: 1985

title: The teaching and learning of te reo Māori in a higher education context: Intensive fast track immersion versus gradual progressive language exposure

authors: Nock, Sophie

subjects: grading of students

abstract: I report here on a comparison of the course grades of Bachelors degree students who are following two different pathways towards a major in te reo Māori - a traditional pathway in which language courses at different levels are spread over three or four years, and an intensive, fast-track, language immersion pathway in which courses in te reo Māori are concentrated into the first year of the degree programme. My findings are that, overall, in terms of course grades at level three, students following the intensive, fast-track, language-immersion pathway out-perform other students in te reo Māori course assessments. Thus, so far as course grades are concerned, many students appear to benefit from the fast track pathway. Whether course grades can be related to proficiency achievements and whether immediate gains are reflected in long-term gains is something that remains to be investigated.

text: The teaching and learning of te reo Māori in a higher education context: Intensive fast track immersion versus gradual progressive language exposure I report here on a comparison of the course grades of Bachelors degree students who are following two different pathways towards a major in te reo Māori - a traditional pathway in which language courses at different levels are spread over three or four years, and an intensive, fast-track, language immersion pathway in which courses in te reo Māori are concentrated into the first year of the degree programme. My findings are that, overall, in terms of course grades at level three, students following the intensive, fast-track, language-immersion pathway out-perform other students in te reo Māori course assessments. Thus, so far as course grades are concerned, many students appear to benefit from the fast track pathway. Whether course grades can be related to proficiency achievements and whether immediate gains are reflected in long-term gains is something that remains to be investigated.

year: 2006