title: A method for assessing the physical recovery of Antarctic desert pavements following human-induced disturbances: A case study in the Ross Sea region of Antarctica

authors: O'Neill, Tanya Ann

subjects: Antarctica

abstract: With increasing visitor numbers an understanding of the impacts of human activities in Antarctic terrestrial environments has become important. The objective of this study was to develop a means for assessing recovery of the ground surface desert pavement following physical disturbance. A set of 11 criteria were identified to assess desert pavement recovery. Assessed criteria were: embeddedness of surface clasts; impressions of removed clasts; degree of clast surface weathering; % overturned clasts; salt on underside of clasts; development of salt coatings; armouring per m ²; colour contrast; evidence of subsidence/melt out; accumulation of salt on cut surfaces; and evidence of patterned ground development. Recovery criteria were assigned a severity/extent rating on a scale from zero to four, zero being highly disturbed, and four being undisturbed. A relative % recovery for each criteria was calculated for each site by comparison with a nearby undisturbed control area, and an overall Mean Recovery Index (MRI) was assigned to each pavement surface.To test the method, 54 sites in the Ross Sea region of Antarctica were investigated including areas disturbed by: bulldozer scraping for road-fill, contouring for infrastructure, geotechnical investigations, and experimental treading trial sites. Disturbances had occurred at timescales ranging from one week to 50 years prior to assessment. The extent of desert pavement recovery at the sites investigated in this study was higher than anticipated. Fifty of the 54 sites investigated were in an intermediate, or higher, stage of desert pavement recovery, 30 sites were in an advanced stage of recovery, and four sites were indistinguishable from adjacent control sites (MRI = 100%). It was found that active surfaces, such as the gravel beach deposits at the Greenpeace World Park Base site at Cape Evans, the aeolian sand deposits at Bull Pass, and the alluvial fan deposits of the Loop Moraine field campsite, recovered relatively quickly, whereas less active sites, such as the bulldozed tracks at Marble Point, and Williams Field to McMurdo Station pipeline site on Ross Island, showed only intermediate recovery 20-30 years after disturbance. The slabby grano-diorite surface material at the former Vanda Station site, meant that the impacts that had occurred were hard to detect following decommissioning of the station and site remediation. Desert pavements disturbed by randomly dispersed footprints, temporary field campsites at the Loop Moraine and VXE6 Pond in the Wright Valley, recovered to be undetectable (MRI = 100%) within five years, whereas track formation from repeated trampling, particularly the concentration of larger clasts along the margin of a confined track, persisted for over 15 years (MRI = 82%). The recovery assessment method developed in this study has environmental management applications and potential to advance our ability to predict the recovery of desert pavement following human impacts from activities in Antarctica

text: A method for assessing the physical recovery of Antarctic desert pavements following human-induced disturbances: A case study in the Ross Sea region of Antarctica With increasing visitor numbers an understanding of the impacts of human activities in Antarctic terrestrial environments has become important. The objective of this study was to develop a means for assessing recovery of the ground surface desert pavement following physical disturbance. A set of 11 criteria were identified to assess desert pavement recovery. Assessed criteria were: embeddedness of surface clasts; impressions of removed clasts; degree of clast surface weathering; % overturned clasts; salt on underside of clasts; development of salt coatings; armouring per m ²; colour contrast; evidence of subsidence/melt out; accumulation of salt on cut surfaces; and evidence of patterned ground development. Recovery criteria were assigned a severity/extent rating on a scale from zero to four, zero being highly disturbed, and four being undisturbed. A relative % recovery for each criteria was calculated for each site by comparison with a nearby undisturbed control area, and an overall Mean Recovery Index (MRI) was assigned to each pavement surface.To test the method, 54 sites in the Ross Sea region of Antarctica were investigated including areas disturbed by: bulldozer scraping for road-fill, contouring for infrastructure, geotechnical investigations, and experimental treading trial sites. Disturbances had occurred at timescales ranging from one week to 50 years prior to assessment. The extent of desert pavement recovery at the sites investigated in this study was higher than anticipated. Fifty of the 54 sites investigated were in an intermediate, or higher, stage of desert pavement recovery, 30 sites were in an advanced stage of recovery, and four sites were indistinguishable from adjacent control sites (MRI = 100%). It was found that active surfaces, such as the gravel beach deposits at the Greenpeace World Park Base site at Cape Evans, the aeolian sand deposits at Bull Pass, and the alluvial fan deposits of the Loop Moraine field campsite, recovered relatively quickly, whereas less active sites, such as the bulldozed tracks at Marble Point, and Williams Field to McMurdo Station pipeline site on Ross Island, showed only intermediate recovery 20-30 years after disturbance. The slabby grano-diorite surface material at the former Vanda Station site, meant that the impacts that had occurred were hard to detect following decommissioning of the station and site remediation. Desert pavements disturbed by randomly dispersed footprints, temporary field campsites at the Loop Moraine and VXE6 Pond in the Wright Valley, recovered to be undetectable (MRI = 100%) within five years, whereas track formation from repeated trampling, particularly the concentration of larger clasts along the margin of a confined track, persisted for over 15 years (MRI = 82%). The recovery assessment method developed in this study has environmental management applications and potential to advance our ability to predict the recovery of desert pavement following human impacts from activities in Antarctica

year: 2012

title: Cross-cultural validation of the stroke riskometer using generalizability theory (vol 11, 19064, 2021)

authors: Medvedev, Oleg N.

subjects: Science & Technology

abstract: The Stroke Riskometer mobile application is a novel, validated way to provide personalized stroke risk assessment for individuals and motivate them to reduce their risks. Although this app is being used worldwide, its reliability across different countries has not yet been rigorously investigated using appropriate methodology. The Generalizability Theory (G-Theory) is an advanced statistical method suitable for examining reliability and generalizability of assessment scores across different samples, cultural and other contexts and for evaluating sources of measurement errors. G-Theory was applied to the Stroke Riskometer data sampled from 1300 participants in 13 countries using two-facet nested observational design (person by item nested in the country). The Stroke Riskometer demonstrated strong reliability in measuring stroke risks across the countries with coefficients G relative and absolute of 0.84, 95%CI [0.79; 0.89] and 0.82, 95%CI [0.76; 0.88] respectively. D-study analyses revealed that the Stroke Riskometer has optimal reliability in its current form in measuring stroke risk for each country and no modifications are required. These results suggest that the Stroke Riskometer’s scores are generalizable across sample population and countries permitting cross-cultural comparisons. Further studies investigating reliability of the Stroke Riskometer over time in longitudinal study design are warranted.

text: Cross-cultural validation of the stroke riskometer using generalizability theory (vol 11, 19064, 2021) The Stroke Riskometer mobile application is a novel, validated way to provide personalized stroke risk assessment for individuals and motivate them to reduce their risks. Although this app is being used worldwide, its reliability across different countries has not yet been rigorously investigated using appropriate methodology. The Generalizability Theory (G-Theory) is an advanced statistical method suitable for examining reliability and generalizability of assessment scores across different samples, cultural and other contexts and for evaluating sources of measurement errors. G-Theory was applied to the Stroke Riskometer data sampled from 1300 participants in 13 countries using two-facet nested observational design (person by item nested in the country). The Stroke Riskometer demonstrated strong reliability in measuring stroke risks across the countries with coefficients G relative and absolute of 0.84, 95%CI [0.79; 0.89] and 0.82, 95%CI [0.76; 0.88] respectively. D-study analyses revealed that the Stroke Riskometer has optimal reliability in its current form in measuring stroke risk for each country and no modifications are required. These results suggest that the Stroke Riskometer’s scores are generalizable across sample population and countries permitting cross-cultural comparisons. Further studies investigating reliability of the Stroke Riskometer over time in longitudinal study design are warranted.

year: 2021-10-11

title: Youth Development Circles: A Report on a School Trial

authors: Hannah, Belinda Anne

subjects: Youth Development Circles

abstract: This research traces the development and trial of the Youth Development Circle (YDC) process in a low decile secondary school in a rural community in Aotearoa New Zealand. Youth Development Circles are an intervention based on restorative justice principles initially proposed by Braithwaite (2004). They were originally suggested as a strategy for use in an alternative education centre or “activity centre”.  Increasing use of restorative approaches has enabled many schools to make significant progress in reducing suspensions, but there remains a concern for students whose behaviour is at the more serious end of the spectrum - who are at risk of suspension, or exclusion, after multiple stand-downs from school.  The possibilities for the use of YDC were proposed to the school by the researcher, who is a Deputy Principal responsible for behaviour management and pastoral care.  This proposal was supported fully by the school’s staff and Board of Trustees.  The YDC process documented in this study was developed by the researcher, informed by a range of sources including Youth Development Circles, Judge McElrea’s proposed School Community Conference (1996), and Hui Whakatika, developed at the University of Waikato (2003).  Participation in the circles was a condition for the student to remain at the school. The school is a state school, with a roll of approximately 800. The ethnic breakdown of the students is 56% Māori and 39% NZ European with 5% of Pasifika, Asian and other.  

The YDC is a deliberate and careful process which aims to bring increased focus on the individual student and their educational outcomes, through engaging a community of care in supporting them. There were many anticipated benefits of the YDC for the student. Such benefits included an opportunity to establish and maintain healthy relationships of trust (within which negative experiences can be learned from), a re-establishment of trust, improved self-confidence and improved educational outcomes. The circles included members of the student’s whānau/family, a kaumātua/elder who cared about them, and representatives from local Police, Social Welfare, and the school.  The circles were studied over a period of one year.  Circles met regularly throughout this time, at increasing intervals.

A mixed method case study approach was used for this research which includes the collection of both quantitative and qualitative data. The study evaluated the effectiveness of the YDCs by analysing student behaviour, attendance and achievement KAMAR data, minutes of each circle meeting, and interviews with circle participants.


Three student case studies are presented.  The stories have had details altered and pseudonyms used to protect the persons involved. All the students completed the academic year without receiving a further stand down or suspension.  The data showed an improvement in student attendance, achievement and engagement in all three case studies.  Other outcomes include reflections on the process used, strategies for implementation in the school, and factors that either hindered or supported student, family or community involvement in YDCs. 

This exploratory study suggests that the Youth Development Circle could offer a unique possibility for inter-sectorial collaboration in the field of restorative justice.

text: Youth Development Circles: A Report on a School Trial This research traces the development and trial of the Youth Development Circle (YDC) process in a low decile secondary school in a rural community in Aotearoa New Zealand. Youth Development Circles are an intervention based on restorative justice principles initially proposed by Braithwaite (2004). They were originally suggested as a strategy for use in an alternative education centre or “activity centre”.  Increasing use of restorative approaches has enabled many schools to make significant progress in reducing suspensions, but there remains a concern for students whose behaviour is at the more serious end of the spectrum - who are at risk of suspension, or exclusion, after multiple stand-downs from school.  The possibilities for the use of YDC were proposed to the school by the researcher, who is a Deputy Principal responsible for behaviour management and pastoral care.  This proposal was supported fully by the school’s staff and Board of Trustees.  The YDC process documented in this study was developed by the researcher, informed by a range of sources including Youth Development Circles, Judge McElrea’s proposed School Community Conference (1996), and Hui Whakatika, developed at the University of Waikato (2003).  Participation in the circles was a condition for the student to remain at the school. The school is a state school, with a roll of approximately 800. The ethnic breakdown of the students is 56% Māori and 39% NZ European with 5% of Pasifika, Asian and other.  

The YDC is a deliberate and careful process which aims to bring increased focus on the individual student and their educational outcomes, through engaging a community of care in supporting them. There were many anticipated benefits of the YDC for the student. Such benefits included an opportunity to establish and maintain healthy relationships of trust (within which negative experiences can be learned from), a re-establishment of trust, improved self-confidence and improved educational outcomes. The circles included members of the student’s whānau/family, a kaumātua/elder who cared about them, and representatives from local Police, Social Welfare, and the school.  The circles were studied over a period of one year.  Circles met regularly throughout this time, at increasing intervals.

A mixed method case study approach was used for this research which includes the collection of both quantitative and qualitative data. The study evaluated the effectiveness of the YDCs by analysing student behaviour, attendance and achievement KAMAR data, minutes of each circle meeting, and interviews with circle participants.


Three student case studies are presented.  The stories have had details altered and pseudonyms used to protect the persons involved. All the students completed the academic year without receiving a further stand down or suspension.  The data showed an improvement in student attendance, achievement and engagement in all three case studies.  Other outcomes include reflections on the process used, strategies for implementation in the school, and factors that either hindered or supported student, family or community involvement in YDCs. 

This exploratory study suggests that the Youth Development Circle could offer a unique possibility for inter-sectorial collaboration in the field of restorative justice.

year: 2015