title: Esterase catalysis of substrate vapour: enzyme activity occurs at very low hydration

authors: Lind, Penelope A.

subjects: hydrolase

abstract: It has been generally accepted that enzyme activity requires a minimal hydration of about 0.2 g H2O g⁻¹ protein. This fits well with evidence that hydration above this level is associated with the onset of intramolecular motions. The influence of enzyme hydration on the hydrolysis of substrate by Candida rugosa Lipase B and pig liver esterase was investigated. Each enzyme was studied as a powder at various hydration levels, using vapour phase ethyl butyrate as substrate. This procedure allows the separation of those effects that are due to hydration from those arising from diffusional constraints. We found hydrolytic activity in both enzymes at all hydration levels above zero (between 0.054–0.47 and 0.029–0.60 g H2O g⁻¹ protein, respectively) that were investigated. The lowest hydration level investigated, <0.03 g H2O g⁻¹ enzyme, corresponded to a water/enzyme mole ratio of 100 and a coverage of about 10% of the enzyme surface by water molecules. The hydrolytic activity of both enzymes was dependent on protein hydration. However, since the hydrolysis of ethyl butyrate requires water as a second substrate, the absence of activity at zero hydration does not rule out the possibility of enzyme activity in the absence of water. These results suggest that the properties conferred on proteins by water, at least above 10% surface coverage (in this case corresponding to a hydration level of 0.03 g H2O g⁻¹ protein), are not a requirement for enzyme catalysis.

text: Esterase catalysis of substrate vapour: enzyme activity occurs at very low hydration It has been generally accepted that enzyme activity requires a minimal hydration of about 0.2 g H2O g⁻¹ protein. This fits well with evidence that hydration above this level is associated with the onset of intramolecular motions. The influence of enzyme hydration on the hydrolysis of substrate by Candida rugosa Lipase B and pig liver esterase was investigated. Each enzyme was studied as a powder at various hydration levels, using vapour phase ethyl butyrate as substrate. This procedure allows the separation of those effects that are due to hydration from those arising from diffusional constraints. We found hydrolytic activity in both enzymes at all hydration levels above zero (between 0.054–0.47 and 0.029–0.60 g H2O g⁻¹ protein, respectively) that were investigated. The lowest hydration level investigated, <0.03 g H2O g⁻¹ enzyme, corresponded to a water/enzyme mole ratio of 100 and a coverage of about 10% of the enzyme surface by water molecules. The hydrolytic activity of both enzymes was dependent on protein hydration. However, since the hydrolysis of ethyl butyrate requires water as a second substrate, the absence of activity at zero hydration does not rule out the possibility of enzyme activity in the absence of water. These results suggest that the properties conferred on proteins by water, at least above 10% surface coverage (in this case corresponding to a hydration level of 0.03 g H2O g⁻¹ protein), are not a requirement for enzyme catalysis.

year: 2004-10

title: The associations between physical-test performance and match performance in women’s rugby sevens players

authors: Sella, Francesco Stefano

abstract: Evaluating the relationships between physical-test and match performance in team sports could be useful for training prescription and athlete evaluation. Here we investigated these relationships in women’s Rugby Sevens. Thirty provincial-representative players performed Bronco-fitness, countermovement-jump, acceleration, speed, and strength tests within two weeks before a two-day tournament. Match-running and match-action performance measures were provided by GPS units and video analysis. Generalised and general linear mixed models were employed to estimate the effect of a two standard-deviation difference in physical test measures on match measures. Effect magnitudes were assessed via standardisation (using the between player SD) and, for effects on tries scored, also via match winning (based on simulating matches). Evidence for substantial and trivial true magnitudes was provided by one-sided interval-hypothesis tests and Bayesian analysis. There was good evidence of positive effects of many physical-test measures on match high-intensity running, with large effects for jump height and acceleration. There was some evidence of small-moderate positive effects of speed and Bronco, and of small-moderate negative effects of maximal strength and jump height, on match total running and high intensity changes in speed. The evidence was generally inadequate for associations between physical-test measures and match actions, but there was good evidence of small-large positive effects of back squat and jump height on tries scored. Enhancing players’ jump height and back-squat performance might therefore increase the likelihood of match success in women’s Rugby Sevens.

text: The associations between physical-test performance and match performance in women’s rugby sevens players Evaluating the relationships between physical-test and match performance in team sports could be useful for training prescription and athlete evaluation. Here we investigated these relationships in women’s Rugby Sevens. Thirty provincial-representative players performed Bronco-fitness, countermovement-jump, acceleration, speed, and strength tests within two weeks before a two-day tournament. Match-running and match-action performance measures were provided by GPS units and video analysis. Generalised and general linear mixed models were employed to estimate the effect of a two standard-deviation difference in physical test measures on match measures. Effect magnitudes were assessed via standardisation (using the between player SD) and, for effects on tries scored, also via match winning (based on simulating matches). Evidence for substantial and trivial true magnitudes was provided by one-sided interval-hypothesis tests and Bayesian analysis. There was good evidence of positive effects of many physical-test measures on match high-intensity running, with large effects for jump height and acceleration. There was some evidence of small-moderate positive effects of speed and Bronco, and of small-moderate negative effects of maximal strength and jump height, on match total running and high intensity changes in speed. The evidence was generally inadequate for associations between physical-test measures and match actions, but there was good evidence of small-large positive effects of back squat and jump height on tries scored. Enhancing players’ jump height and back-squat performance might therefore increase the likelihood of match success in women’s Rugby Sevens.

year: 2022-11-18

title: The Treaty, tikanga Māori, ecosystem-based management, mainstream law and power sharing for environmental integrity in Aotearoa New Zealand – possible ways forward

authors: Joseph, Robert

subjects: Maori, ecosystem-based management, coastal marine estate, sustainability, Treaty of Waitangi

abstract: Ecosystem-based management (EBM) has become an appropriate international response for addressing alarming global environmental degradation trends. EBM is designed and executed as an adaptive, learning-based process that applies the following common international principles:
•	the connections and relationships within an ecosystem;
•	the cumulative impacts that affect marine welfare; 
•	focus on maintaining the natural structure and function of ecosystems and their productivity;
•	incorporate human use and values of ecosystems in managing the resource;
•	recognise that ecosystems are dynamic and constantly changing;
•	are based on a shared vision of all key participants; and
•	are based on scientific knowledge, adopted by continual learning and monitoring.

The New Zealand Sustainable Seas National Science Challenge agrees with these EBM principles but has adapted them into an Aotearoa New Zealand theoretical approach that fundamentally acknowledges mātauranga and tikanga Māori law hence the following Aotearoa New Zealand EBM principles:
•	a co-governance and co-design structure that recognises the Māori constitutional relationship and mana whenua at all levels (whānau, hapū, iwi), together with the guiding principles of mauri, whakapapa, kaitiakitanga, mātauranga-a-iwi and mātauranga-a-hapū;
•	is place and time-specific, recognising/understanding the ecosystem as a whole in all its ecological complexities and connectedness and addressing cumulative and multiple stressors;
•	acknowledges humans as ecosystem components with multiple values;
•	views long-term sustainability as a fundamental value, in particular maintaining values and uses for future generations;
•	includes collaborative and participatory management throughout the whole process, considering all values and involving all interested parties from agencies and iwi to industries, whānau, hapū and local communities;
•	has clear goals and objectives based on knowledge; and
•	includes adaptive management, appropriate monitoring and acknowledgement of uncertainty.

The report focuses on analysing EBM through the incorporation of mātauranga and tikanga Māori and power sharing through Treaty partnerships over the marine and coastal estate.

text: The Treaty, tikanga Māori, ecosystem-based management, mainstream law and power sharing for environmental integrity in Aotearoa New Zealand – possible ways forward Ecosystem-based management (EBM) has become an appropriate international response for addressing alarming global environmental degradation trends. EBM is designed and executed as an adaptive, learning-based process that applies the following common international principles:
•	the connections and relationships within an ecosystem;
•	the cumulative impacts that affect marine welfare; 
•	focus on maintaining the natural structure and function of ecosystems and their productivity;
•	incorporate human use and values of ecosystems in managing the resource;
•	recognise that ecosystems are dynamic and constantly changing;
•	are based on a shared vision of all key participants; and
•	are based on scientific knowledge, adopted by continual learning and monitoring.

The New Zealand Sustainable Seas National Science Challenge agrees with these EBM principles but has adapted them into an Aotearoa New Zealand theoretical approach that fundamentally acknowledges mātauranga and tikanga Māori law hence the following Aotearoa New Zealand EBM principles:
•	a co-governance and co-design structure that recognises the Māori constitutional relationship and mana whenua at all levels (whānau, hapū, iwi), together with the guiding principles of mauri, whakapapa, kaitiakitanga, mātauranga-a-iwi and mātauranga-a-hapū;
•	is place and time-specific, recognising/understanding the ecosystem as a whole in all its ecological complexities and connectedness and addressing cumulative and multiple stressors;
•	acknowledges humans as ecosystem components with multiple values;
•	views long-term sustainability as a fundamental value, in particular maintaining values and uses for future generations;
•	includes collaborative and participatory management throughout the whole process, considering all values and involving all interested parties from agencies and iwi to industries, whānau, hapū and local communities;
•	has clear goals and objectives based on knowledge; and
•	includes adaptive management, appropriate monitoring and acknowledgement of uncertainty.

The report focuses on analysing EBM through the incorporation of mātauranga and tikanga Māori and power sharing through Treaty partnerships over the marine and coastal estate.

year: 2019-07-30