title: Toxicity assessment of chlorophenols using a mediated microbial toxicity assay

authors: Pasco, Neil F.

subjects: direct toxicity assessment

abstract: While direct toxicity assessment (DTA) is now widely recognised as a useful tool for environmental risk assessment, many existing tests fail to meet end-user needs. This article describes the significant progress made to the MICREDOX® DTA assay, developed at Lincoln Ventures Ltd, brought about by miniaturising this assay to a multi-well plate format combined with limiting current microelectrode transduction. The benefits have been reduced: preparation time, reduced assay time, lower material costs and a higher level of replication achieved. To validate the precision of the miniaturised format, the concentrations required to cause a 50% decrease in signal (EC50) by an archetypal group of toxicants, the chlorophenols, were determined using two terrestrial bacterial strains, Escherichia coli K12 and Klebsiella oxytoca 13183. The assay time was then reduced by stepwise adjustment of the incubation time, from 60 down to 5 min, and the EC50s reported by E. coli to each of the toxicants after 45, 30, 15 and 5 min incubations were determined. The results obtained match closely with those reported by the Activated Sludge Respiration Inhibition Test and confirm the miniaturised multi-well plate MICREDOX® DTA assay reliably reports representative EC50 values for these toxicants. The previously described trends of increasing toxicity with increasing chlorine substitution and the observation that meta-substituted chlorophenols are more toxic than their ortho-substituted counterparts are also confirmed. The ability to monitor toxicity using terrestrial organisms, in volumes amenable to multi-well microtitre plates and incubations requiring only a few minutes, facilitates the rapid generation of highly reproducible, easy to operate and inexpensive DTA measurements.

text: Toxicity assessment of chlorophenols using a mediated microbial toxicity assay While direct toxicity assessment (DTA) is now widely recognised as a useful tool for environmental risk assessment, many existing tests fail to meet end-user needs. This article describes the significant progress made to the MICREDOX® DTA assay, developed at Lincoln Ventures Ltd, brought about by miniaturising this assay to a multi-well plate format combined with limiting current microelectrode transduction. The benefits have been reduced: preparation time, reduced assay time, lower material costs and a higher level of replication achieved. To validate the precision of the miniaturised format, the concentrations required to cause a 50% decrease in signal (EC50) by an archetypal group of toxicants, the chlorophenols, were determined using two terrestrial bacterial strains, Escherichia coli K12 and Klebsiella oxytoca 13183. The assay time was then reduced by stepwise adjustment of the incubation time, from 60 down to 5 min, and the EC50s reported by E. coli to each of the toxicants after 45, 30, 15 and 5 min incubations were determined. The results obtained match closely with those reported by the Activated Sludge Respiration Inhibition Test and confirm the miniaturised multi-well plate MICREDOX® DTA assay reliably reports representative EC50 values for these toxicants. The previously described trends of increasing toxicity with increasing chlorine substitution and the observation that meta-substituted chlorophenols are more toxic than their ortho-substituted counterparts are also confirmed. The ability to monitor toxicity using terrestrial organisms, in volumes amenable to multi-well microtitre plates and incubations requiring only a few minutes, facilitates the rapid generation of highly reproducible, easy to operate and inexpensive DTA measurements.

year: 2008

title: Traditional kava use and body sway: A pilot investigation

authors: Aporosa, S. 'Apo'

abstract: Introduction The (traditionally influenced) consumption of kava (Piper methysticum) has been associated with increased body sway, raising concerns about fall risk. However, studies typically utilise pill-styled kava extracts with a lack of understanding regarding experienced naturalistic kava drinkers. This pilot study investigated the effects of naturalistic kava consumption over a six-hour period on postural control. Methods Six experienced male kava drinkers consumed 100ml of kava every 10 minutes over six hours in a culturally responsive setting. Postural control was examined at three time points (Pre, Mid, and Post) using a 30-seconds eyes-closed feet-together postural balance test conducted on a 3D force plate. Centre of pressure path length, average velocity, and area of the 95th percentile ellipse data were extracted and compared between time points using a one-way repeated measures ANOVA. Findings There were no significant differences in the centre of pressure parameters. Based on the Pre and Post differences for path length and average velocity logged values, this study would require 19 participants to achieve an 80% power and 5% significance level. Discussion Irrespective of limited sample size, our preliminary results do not support that kava consumption negatively affects postural control, findings that appear to be corroborated by a recent neuroscience study. The perceived risks of naturalistic kava consumption with regards to falls may be overstated. Further study on the physiological implications of kava consumption in naturalistic settings is needed to quantify the actual risks. Highlights• Kava is a culturally significant drink for Pacific people• Anecdotal reports describe impaired balance following high traditional use volumes• Postural control was tested during and following kava use in a pilot study• Contrary to hypothesis, results do not show that kava negatively affects postural control.

text: Traditional kava use and body sway: A pilot investigation Introduction The (traditionally influenced) consumption of kava (Piper methysticum) has been associated with increased body sway, raising concerns about fall risk. However, studies typically utilise pill-styled kava extracts with a lack of understanding regarding experienced naturalistic kava drinkers. This pilot study investigated the effects of naturalistic kava consumption over a six-hour period on postural control. Methods Six experienced male kava drinkers consumed 100ml of kava every 10 minutes over six hours in a culturally responsive setting. Postural control was examined at three time points (Pre, Mid, and Post) using a 30-seconds eyes-closed feet-together postural balance test conducted on a 3D force plate. Centre of pressure path length, average velocity, and area of the 95th percentile ellipse data were extracted and compared between time points using a one-way repeated measures ANOVA. Findings There were no significant differences in the centre of pressure parameters. Based on the Pre and Post differences for path length and average velocity logged values, this study would require 19 participants to achieve an 80% power and 5% significance level. Discussion Irrespective of limited sample size, our preliminary results do not support that kava consumption negatively affects postural control, findings that appear to be corroborated by a recent neuroscience study. The perceived risks of naturalistic kava consumption with regards to falls may be overstated. Further study on the physiological implications of kava consumption in naturalistic settings is needed to quantify the actual risks. Highlights• Kava is a culturally significant drink for Pacific people• Anecdotal reports describe impaired balance following high traditional use volumes• Postural control was tested during and following kava use in a pilot study• Contrary to hypothesis, results do not show that kava negatively affects postural control.

year: 2022

title: Investigating the understanding and implementation of Ka Hikitia, in a New Zealand primary school

authors: Evans, Mary

subjects: Ka Hikitia

abstract: In New Zealand, the education system has underserved Māori learners for many years, with various factors contributing to this underperformance.  Many of these factors stem from racism and bias, conscious or unconscious, inherent in our system (Ministry of Education, 2019b).  Ka Hikitia Accelerating Success 2013 - 2017 (Ministry of Education, 2013a) set about to make transformative change in schools.  This research presents an investigation into the understanding and implementation of Ka Hikitia, in a New Zealand primary school.  
The research was guided by culturally responsive methodologies, bringing together both kaupapa Māori and critical theories (Berryman, 2013b).  Participants’ understandings and how these understandings transferred into their practice was determined through a case study.  The rich information generated within the case was analysed using grounded theory.  The main source of information came from interviewing the management team and teaching staff members.  As an insider/outsider researcher and also a participant, some of my information came from my own observations and knowledge of the school. Some attendance and achievement data held by the school also informed the case.  
The Office of the Auditor-General (2016b) contended that Ka Hikitia was a well-worded policy but, due to a lack of understanding of the policy in many schools, it was poorly implemented nationwide.  In this school, despite the good leadership and hard-working teachers, staff had difficulty fully understanding and therefore implementing the Ka Hikitia strategy as it was intended.  Strong relationships between teachers and students were evident throughout the study, however, stronger relationships were needed between the school and the wider Māori community.  The research shows that, despite the good intentions of the teachers, to fully implement the intent of Ka Hikitia, educators need to be committed to te ao Māori.  
The Ministry of Education plans to relaunch a further iteration of Ka Hikitia this year, supported by another initiative, Te Hurihanganui.  For this iteration to be successful, more effective implementation systems are required that will enable Māori students to enjoy and achieve educational success as Māori.

text: Investigating the understanding and implementation of Ka Hikitia, in a New Zealand primary school In New Zealand, the education system has underserved Māori learners for many years, with various factors contributing to this underperformance.  Many of these factors stem from racism and bias, conscious or unconscious, inherent in our system (Ministry of Education, 2019b).  Ka Hikitia Accelerating Success 2013 - 2017 (Ministry of Education, 2013a) set about to make transformative change in schools.  This research presents an investigation into the understanding and implementation of Ka Hikitia, in a New Zealand primary school.  
The research was guided by culturally responsive methodologies, bringing together both kaupapa Māori and critical theories (Berryman, 2013b).  Participants’ understandings and how these understandings transferred into their practice was determined through a case study.  The rich information generated within the case was analysed using grounded theory.  The main source of information came from interviewing the management team and teaching staff members.  As an insider/outsider researcher and also a participant, some of my information came from my own observations and knowledge of the school. Some attendance and achievement data held by the school also informed the case.  
The Office of the Auditor-General (2016b) contended that Ka Hikitia was a well-worded policy but, due to a lack of understanding of the policy in many schools, it was poorly implemented nationwide.  In this school, despite the good leadership and hard-working teachers, staff had difficulty fully understanding and therefore implementing the Ka Hikitia strategy as it was intended.  Strong relationships between teachers and students were evident throughout the study, however, stronger relationships were needed between the school and the wider Māori community.  The research shows that, despite the good intentions of the teachers, to fully implement the intent of Ka Hikitia, educators need to be committed to te ao Māori.  
The Ministry of Education plans to relaunch a further iteration of Ka Hikitia this year, supported by another initiative, Te Hurihanganui.  For this iteration to be successful, more effective implementation systems are required that will enable Māori students to enjoy and achieve educational success as Māori.

year: 2020