title: Steady state magnetic reconnection in planar geometries

authors: Craig, Ian J.D.

abstract: The problem of nonlinear, steady state magnetic reconnection in incompressible plasmas is considered. A self-consistent treatment is developed which allows a formal analytic solution of the resistive induction equation, valid for all sub-Alfvénic velocity fields. This solution relates the velocity stream function to the global magnetic field structure and highlights several key properties of the resistive system. In particular, the field lines are isobars of uniform current density and characteristics of the velocity stream function. The impact of this analysis on "fast" magnetic reconnection is then considered. Despite strong constraints on the flow topology - no separatrix flows are allowed - fast, nonlinear models can be developed self-consistently. It is shown that the reconnection rate is maintained against reductions in the plasma restrictivity by the increasing amplitude but decreasing width of the current layer aligned to the separatrix. It is concluded that "open" flow topologies allow fast reconnection to continue under conditions which lead to stalling in "closed" or periodic geometries.

text: Steady state magnetic reconnection in planar geometries The problem of nonlinear, steady state magnetic reconnection in incompressible plasmas is considered. A self-consistent treatment is developed which allows a formal analytic solution of the resistive induction equation, valid for all sub-Alfvénic velocity fields. This solution relates the velocity stream function to the global magnetic field structure and highlights several key properties of the resistive system. In particular, the field lines are isobars of uniform current density and characteristics of the velocity stream function. The impact of this analysis on "fast" magnetic reconnection is then considered. Despite strong constraints on the flow topology - no separatrix flows are allowed - fast, nonlinear models can be developed self-consistently. It is shown that the reconnection rate is maintained against reductions in the plasma restrictivity by the increasing amplitude but decreasing width of the current layer aligned to the separatrix. It is concluded that "open" flow topologies allow fast reconnection to continue under conditions which lead to stalling in "closed" or periodic geometries.

year: 1994

title: NCEA level 3 economics and economic literacy in introductory economics at University

authors: Cameron, Michael Patrick

subjects: economic literacy

abstract: In 2003, New Zealand significantly reorganised high school education by moving to a standards-based assessment approach. This paper investigates whether the economics standards are associated with economic understanding using 2008-2011 data from students at the University of Waikato. We find that there is significant association between NCEA economics and economic literacy. However, some standards have a much closer association with economic literacy, in particular AS90631 and AS90632. These standards are the only standards associated with economic literacy for both high aptitude and low aptitude students. An optimal high school course in economics should include these standards as a minimum.

text: NCEA level 3 economics and economic literacy in introductory economics at University In 2003, New Zealand significantly reorganised high school education by moving to a standards-based assessment approach. This paper investigates whether the economics standards are associated with economic understanding using 2008-2011 data from students at the University of Waikato. We find that there is significant association between NCEA economics and economic literacy. However, some standards have a much closer association with economic literacy, in particular AS90631 and AS90632. These standards are the only standards associated with economic literacy for both high aptitude and low aptitude students. An optimal high school course in economics should include these standards as a minimum.

year: 2012-05

title: Treatment and survival disparities by ethnicity in New Zealand women with stage I-III breast cancer tumour subtypes

authors: Lawrenson, Ross

subjects: Science & Technology

abstract: Purpose
This study aims to look at the distribution of different subtypes of stage I–III breast cancer in Māori and Pacific versus non-Māori/Pacific women, and to examine cancer outcomes by ethnicity within these different subtypes.

Method
This study included 9,015 women diagnosed with stage I–III breast cancer between June 2000 and May 2013, recorded in the combined Waikato and Auckland Breast Cancer Registers, who had complete data on ER, PR and HER2 status. Five ER/PR/HER2 subtypes were defined. Kaplan–Meier method and Cox proportional hazards model were used to examine ethnic disparities in breast cancer-specific survival.

Results
Of the 9,015 women, 891 were Māori, 548 were Pacific and 7,576 others. Both Māori and Pacific women were less likely to have triple negative breast cancer compared to others (8.6, 8.9 vs. 13.0%). Pacific women were more than twice as likely to have ER−, PR− and HER2+ cancer than Māori and others (14.2 vs. 6.0%, 6.7%). After adjustment for age, year of diagnosis, stage, grade and treatment, the hazard ratios of breast cancer-specific mortality for Māori and Pacific women with ER+, PR+ and HER2− were 1.52 (95% CI 1.06–2.18) and 1.55 (95% CI 1.04–2.31) compared to others, respectively. Māori women with HER2+ cancer were twice more likely to die of their cancer than others.

Conclusions
Outcomes for Māori and Pacific women could be improved by better treatment regimens especially for those with HER2+ breast cancer and for women with ER+, PR+ and HER2− breast cancer.

text: Treatment and survival disparities by ethnicity in New Zealand women with stage I-III breast cancer tumour subtypes Purpose
This study aims to look at the distribution of different subtypes of stage I–III breast cancer in Māori and Pacific versus non-Māori/Pacific women, and to examine cancer outcomes by ethnicity within these different subtypes.

Method
This study included 9,015 women diagnosed with stage I–III breast cancer between June 2000 and May 2013, recorded in the combined Waikato and Auckland Breast Cancer Registers, who had complete data on ER, PR and HER2 status. Five ER/PR/HER2 subtypes were defined. Kaplan–Meier method and Cox proportional hazards model were used to examine ethnic disparities in breast cancer-specific survival.

Results
Of the 9,015 women, 891 were Māori, 548 were Pacific and 7,576 others. Both Māori and Pacific women were less likely to have triple negative breast cancer compared to others (8.6, 8.9 vs. 13.0%). Pacific women were more than twice as likely to have ER−, PR− and HER2+ cancer than Māori and others (14.2 vs. 6.0%, 6.7%). After adjustment for age, year of diagnosis, stage, grade and treatment, the hazard ratios of breast cancer-specific mortality for Māori and Pacific women with ER+, PR+ and HER2− were 1.52 (95% CI 1.06–2.18) and 1.55 (95% CI 1.04–2.31) compared to others, respectively. Māori women with HER2+ cancer were twice more likely to die of their cancer than others.

Conclusions
Outcomes for Māori and Pacific women could be improved by better treatment regimens especially for those with HER2+ breast cancer and for women with ER+, PR+ and HER2− breast cancer.

year: 2017