title: On the solution of the continuity equation for precipitating electrons in solar flares

authors: Emslie, A. Gordon

subjects: methods: analytical

abstract: Electrons accelerated in solar flares are injected into the surrounding plasma, where they are subjected to the influence of collisional (Coulomb) energy losses. Their evolution is modeled by a partial differential equation describing continuity of electron number. In a recent paper, Dobranskis & Zharkova claim to have found an "updated exact analytical solution" to this continuity equation. Their solution contains an additional term that drives an exponential decrease in electron density with depth, leading them to assert that the well-known solution derived by Brown, Syrovatskii & Shmeleva, and many others is invalid. We show that the solution of Dobranskis & Zharkova results from a fundamental error in the application of the method of characteristics and is hence incorrect. Further, their comparison of the "new" analytical solution with numerical solutions of the Fokker-Planck equation fails to lend support to their result. We conclude that Dobranskis & Zharkova's solution of the universally accepted and well-established continuity equation is incorrect, and that their criticism of the correct solution is unfounded. We also demonstrate the formal equivalence of the approaches of Syrovatskii & Shmeleva and Brown, with particular reference to the evolution of the electron flux and number density (both differential in energy) in a collisional thick target. We strongly urge use of these long-established, correct solutions in future works. © 2014. The American Astronomical Society. All rights reserved.

text: On the solution of the continuity equation for precipitating electrons in solar flares Electrons accelerated in solar flares are injected into the surrounding plasma, where they are subjected to the influence of collisional (Coulomb) energy losses. Their evolution is modeled by a partial differential equation describing continuity of electron number. In a recent paper, Dobranskis & Zharkova claim to have found an "updated exact analytical solution" to this continuity equation. Their solution contains an additional term that drives an exponential decrease in electron density with depth, leading them to assert that the well-known solution derived by Brown, Syrovatskii & Shmeleva, and many others is invalid. We show that the solution of Dobranskis & Zharkova results from a fundamental error in the application of the method of characteristics and is hence incorrect. Further, their comparison of the "new" analytical solution with numerical solutions of the Fokker-Planck equation fails to lend support to their result. We conclude that Dobranskis & Zharkova's solution of the universally accepted and well-established continuity equation is incorrect, and that their criticism of the correct solution is unfounded. We also demonstrate the formal equivalence of the approaches of Syrovatskii & Shmeleva and Brown, with particular reference to the evolution of the electron flux and number density (both differential in energy) in a collisional thick target. We strongly urge use of these long-established, correct solutions in future works. © 2014. The American Astronomical Society. All rights reserved.

year: 2014-09-01

title: Managing soil biodiversity: The New Zealand experience

authors: Morad, Munir

subjects: Soil biodiversity

abstract: Species diversity is a very important component of a healthy soil ecosystem, and a necessary condition for long-term sustainable development. However, it is widely recognised that soil degradation and species extinction are on the increase in New Zealand, as land resources come under pressure from urban expansion and modern agribusiness. New Zealand's soils, flora and fauna have evolved many unique elements during their long isolation from other land masses. Habitat destruction and introduced plants and animals have, therefore, had increasingly detrimental effects on indigenous biodiversity. New Zealand must conserve what remains.

text: Managing soil biodiversity: The New Zealand experience Species diversity is a very important component of a healthy soil ecosystem, and a necessary condition for long-term sustainable development. However, it is widely recognised that soil degradation and species extinction are on the increase in New Zealand, as land resources come under pressure from urban expansion and modern agribusiness. New Zealand's soils, flora and fauna have evolved many unique elements during their long isolation from other land masses. Habitat destruction and introduced plants and animals have, therefore, had increasingly detrimental effects on indigenous biodiversity. New Zealand must conserve what remains.

year: 2004

title: Te kawa whakauru ora: Transformative pathways to flourishing whānau

authors: Raharuhi, Te Urukeiha

subjects: flourishing whānau

abstract: Flourishing is more than a combination of wellbeing factors or the absence of disease. It is a state of vitality, optimism and potential. We flourish when we feel positive about our ability to make choices to improve our lives. We flourish when we have opportunities to make valuable contributions to those we care most about, in ways that are meaningful to us. 

There is a wealth of research about whānau wellbeing. However, it is difficult to discern how it directly benefits whānau. Furthermore, deficit approaches to whānau wellbeing research publicise negative stereotypes that are alienating for Māori and detrimental to our flourishing. Te Kawa Whakauru Ora explores a process of identifying transformative pathways to flourishing whānau. It is not a generic approach that represents whānau as homogenous. Nor does it equate whānau with household or nuclear family. This research inquiry into flourishing whānau occurs within the scope of whakapapa and explores diversity within my whānau. 

This research inquiry compares whānau participation in individual wellbeing activities with participation in whānau events. Whānau events are identified by whānau as the only occasions where we experience whakapapa, whanaungatanga and aspects of flourishing that are unique to our collective wellbeing. The research inquiry then focuses on trialling a process of identifying pathways to flourishing whānau through participation in whānau events. When we participate in whānau events, we simultaneously access many aspects of flourishing to varying degrees. Te reo Māori and Māori concepts that are accessible to all whānau regardless of our level of proficiency, are tools to raise our awareness about these. When coupled with an existing research framework, a process for time series analysis of flourishing whānau is created, allowing us to document and compare the contexts of flourishing experienced at different events. 

The trial process of identifying transformative pathways to flourishing whānau is described in detail throughout this thesis to engage with whānau wanting to document the contexts within which they access flourishing. The research process recognises that the potential for pathways to be transformative increases when these are identified by each whānau. This thesis is thus different from existing research about whānau wellbeing because it demonstrates and strengthens whānau research capability.

text: Te kawa whakauru ora: Transformative pathways to flourishing whānau Flourishing is more than a combination of wellbeing factors or the absence of disease. It is a state of vitality, optimism and potential. We flourish when we feel positive about our ability to make choices to improve our lives. We flourish when we have opportunities to make valuable contributions to those we care most about, in ways that are meaningful to us. 

There is a wealth of research about whānau wellbeing. However, it is difficult to discern how it directly benefits whānau. Furthermore, deficit approaches to whānau wellbeing research publicise negative stereotypes that are alienating for Māori and detrimental to our flourishing. Te Kawa Whakauru Ora explores a process of identifying transformative pathways to flourishing whānau. It is not a generic approach that represents whānau as homogenous. Nor does it equate whānau with household or nuclear family. This research inquiry into flourishing whānau occurs within the scope of whakapapa and explores diversity within my whānau. 

This research inquiry compares whānau participation in individual wellbeing activities with participation in whānau events. Whānau events are identified by whānau as the only occasions where we experience whakapapa, whanaungatanga and aspects of flourishing that are unique to our collective wellbeing. The research inquiry then focuses on trialling a process of identifying pathways to flourishing whānau through participation in whānau events. When we participate in whānau events, we simultaneously access many aspects of flourishing to varying degrees. Te reo Māori and Māori concepts that are accessible to all whānau regardless of our level of proficiency, are tools to raise our awareness about these. When coupled with an existing research framework, a process for time series analysis of flourishing whānau is created, allowing us to document and compare the contexts of flourishing experienced at different events. 

The trial process of identifying transformative pathways to flourishing whānau is described in detail throughout this thesis to engage with whānau wanting to document the contexts within which they access flourishing. The research process recognises that the potential for pathways to be transformative increases when these are identified by each whānau. This thesis is thus different from existing research about whānau wellbeing because it demonstrates and strengthens whānau research capability.

year: 2025