title: Ecological, genetic and cultural status of Solanum aviculare, poroporo (Solanaceae)

authors: Weavers, Graeme Morris

subjects: Solanum aviculare

abstract: Solanum aviculare, endemic to Australasia, is an opportunist pioneer secondary successional plant occupying disturbed and open lowland habitats, and was an important medicinal and cultural species to Māori known as poroporo. It is currently in 'decline', the ecological decline appearing to correspond to a decline in knowledge and cultural use of the species. To gain understanding of the reasons for the decline, enhance ecological knowledge, assist conservation and cultural restoration of Solanum aviculare this research documented the successional role and cycle of regeneration dynamics and tactics, established morphological characteristics, investigated the genetic diversity and recorded cultural and conservation information.
The successional status and role was identified. Growth data identified cohort development and inter-site differences, metadata found height and crown spread growth to be significantly correlated and likely part of an early reproduction and dispersal strategy. Germination of soil cores from differing depths confirmed a viable seed bank exists sufficient for species maintenance. Viable seed spread via animal gut passage was determined by germination and chemical tests, results showed rats passed higher rates of viable seed than birds. Seed germination trials with stratified and fresh seed confirmed temporal and depth behaviour, flowering observation documented temporal differences with the closely allied species Solanum laciniatum, indicating a relationship to stasis induction. Leaf morphology studies documented differences between the two allied species and proposed further nomenclature.
Genetic diversity was investigated through the use of PCR/ISSR techniques. Chloroplast DNA was extracted by CTAB and DNA kit protocols. CTAB extraction was unable to effectively remove RNA, although use of DNA samples with high quantities of RNA confirmed that RNA was not an inhibiting factor in PCR production. The production of consistent reliable ISSR bands proved difficult, with no technical explanation found. ISSR findings indicate that Solanum aviculare is highly monomorphic, consisting of predominant invariant monomorphic loci. Twenty primers were tested with no polymorphic loci
identified and no intra species variation documented. Indications were also that Solanum aviculare and Solanum laciniatum are inter species invariant on monomorphic loci. Monomorphic loci may possibly be the evolutionary markers of generic differentiation within Solanum.
Surveys identified Solanum aviculare as uncommon and rare, existing mainly as single plants or small groups in the majority of areas surveyed. The Threatened and Uncommon Plant listing of Solanum aviculare as an 'at risk declining' species is confirmed and a further Recommendation category proposed. Ecological decline and corresponding decline in cultural use and knowledge of Solanum aviculare was identified through specialist interviews; appearing to be related to removal from Māori of control over their land. The name poroporo being now associated mainly with non indigenous Solanum species. Māori cultural concepts in practice were highlighted as fundamentally important to reversing the decline, with an example of a successful traditional practice based (tikanga) integrative collaborative restoration program being documented.
This research forwards that optimal collaborative solutions, programs integrating scientific and tikanga knowledge and practices, provide the best opportunity of reversing the declining trend and for increasing and maintaining knowledge associated with the traditional role of poroporo.

text: Ecological, genetic and cultural status of Solanum aviculare, poroporo (Solanaceae) Solanum aviculare, endemic to Australasia, is an opportunist pioneer secondary successional plant occupying disturbed and open lowland habitats, and was an important medicinal and cultural species to Māori known as poroporo. It is currently in 'decline', the ecological decline appearing to correspond to a decline in knowledge and cultural use of the species. To gain understanding of the reasons for the decline, enhance ecological knowledge, assist conservation and cultural restoration of Solanum aviculare this research documented the successional role and cycle of regeneration dynamics and tactics, established morphological characteristics, investigated the genetic diversity and recorded cultural and conservation information.
The successional status and role was identified. Growth data identified cohort development and inter-site differences, metadata found height and crown spread growth to be significantly correlated and likely part of an early reproduction and dispersal strategy. Germination of soil cores from differing depths confirmed a viable seed bank exists sufficient for species maintenance. Viable seed spread via animal gut passage was determined by germination and chemical tests, results showed rats passed higher rates of viable seed than birds. Seed germination trials with stratified and fresh seed confirmed temporal and depth behaviour, flowering observation documented temporal differences with the closely allied species Solanum laciniatum, indicating a relationship to stasis induction. Leaf morphology studies documented differences between the two allied species and proposed further nomenclature.
Genetic diversity was investigated through the use of PCR/ISSR techniques. Chloroplast DNA was extracted by CTAB and DNA kit protocols. CTAB extraction was unable to effectively remove RNA, although use of DNA samples with high quantities of RNA confirmed that RNA was not an inhibiting factor in PCR production. The production of consistent reliable ISSR bands proved difficult, with no technical explanation found. ISSR findings indicate that Solanum aviculare is highly monomorphic, consisting of predominant invariant monomorphic loci. Twenty primers were tested with no polymorphic loci
identified and no intra species variation documented. Indications were also that Solanum aviculare and Solanum laciniatum are inter species invariant on monomorphic loci. Monomorphic loci may possibly be the evolutionary markers of generic differentiation within Solanum.
Surveys identified Solanum aviculare as uncommon and rare, existing mainly as single plants or small groups in the majority of areas surveyed. The Threatened and Uncommon Plant listing of Solanum aviculare as an 'at risk declining' species is confirmed and a further Recommendation category proposed. Ecological decline and corresponding decline in cultural use and knowledge of Solanum aviculare was identified through specialist interviews; appearing to be related to removal from Māori of control over their land. The name poroporo being now associated mainly with non indigenous Solanum species. Māori cultural concepts in practice were highlighted as fundamentally important to reversing the decline, with an example of a successful traditional practice based (tikanga) integrative collaborative restoration program being documented.
This research forwards that optimal collaborative solutions, programs integrating scientific and tikanga knowledge and practices, provide the best opportunity of reversing the declining trend and for increasing and maintaining knowledge associated with the traditional role of poroporo.

year: 2010

title: Social deprivation in New Zealand

authors: Harcourt, Brian James

subjects: Deprivation

abstract: The purpose of the thesis was to better understand the phenomenon of social deprivation, world-wide and in particular in New Zealand. Social deprivation has been defined in many ways with multiple surrogates used to ‘measure’ its prevalence. The aim of this research was to provide examples of the lived experiences of social deprivation.

Social constructivist and interpretive lenses were used to portray the voices of those living in deprivation, as well as those people tasked to assist them. A narrative case study approach was employed with participants from Whānau Ora. This social and health initiative offered a holistic approach to assistance in contrast to the usual State agencies operating in a silo fashion, with separate agencies providing for different aspects of social deprivation such as housing, employment, mental health and other services. The approach of Whānau Ora is to support clients’ needs holistically and encourage people to develop their own plans for self- improvement. Navigators help people develop their plans and assist in their interactions with the various State agencies whose services they require. This approach allowed a better understanding of ways to overcome people’s feelings of powerlessness and desperation.

The findings from the study lead to suggestions for the application of evidence-based, complementary, integrated assistance programmes rather than having segregated public service agencies acting independently. The recommendations are simple yet require profound changes in public service operations when attempting to ameliorate or prevent social deprivation among citizens.

text: Social deprivation in New Zealand The purpose of the thesis was to better understand the phenomenon of social deprivation, world-wide and in particular in New Zealand. Social deprivation has been defined in many ways with multiple surrogates used to ‘measure’ its prevalence. The aim of this research was to provide examples of the lived experiences of social deprivation.

Social constructivist and interpretive lenses were used to portray the voices of those living in deprivation, as well as those people tasked to assist them. A narrative case study approach was employed with participants from Whānau Ora. This social and health initiative offered a holistic approach to assistance in contrast to the usual State agencies operating in a silo fashion, with separate agencies providing for different aspects of social deprivation such as housing, employment, mental health and other services. The approach of Whānau Ora is to support clients’ needs holistically and encourage people to develop their own plans for self- improvement. Navigators help people develop their plans and assist in their interactions with the various State agencies whose services they require. This approach allowed a better understanding of ways to overcome people’s feelings of powerlessness and desperation.

The findings from the study lead to suggestions for the application of evidence-based, complementary, integrated assistance programmes rather than having segregated public service agencies acting independently. The recommendations are simple yet require profound changes in public service operations when attempting to ameliorate or prevent social deprivation among citizens.

year: 2019

title: Ensembles of restricted Hoeffding trees

authors: Bifet, Albert

subjects: design

abstract: The success of simple methods for classification shows that is is often not necessary to model complex attribute interactions to obtain good classification accuracy on practical problems. In this article, we propose to exploit this phenomenon in the data stream context by building an ensemble of Hoeffding trees that are each limited to a small subset of attributes. In this way, each tree is restricted to model interactions between attributes in its corresponding subset. Because it is not known a priori which attribute subsets are relevant for prediction, we build exhaustive ensembles that consider all possible attribute subsets of a given size. As the resulting Hoeffding trees are not all equally important, we weigh them in a suitable manner to obtain accurate classifications. This is done by combining the log-odds of their probability estimates using sigmoid perceptrons, with one perceptron per class. We propose a mechanism for setting the perceptrons' learning rate using the ADWIN change detection method for data streams, and also use ADWIN to reset ensemble members (i.e., Hoeffding trees) when they no longer perform well. Our experiments show that the resulting ensemble classifier outperforms bagging for data streams in terms of accuracy when both are used in conjunction with adaptive naive Bayes Hoeffding trees, at the expense of runtime and memory consumption. We also show that our stacking method can improve the performance of a bagged ensemble.

text: Ensembles of restricted Hoeffding trees The success of simple methods for classification shows that is is often not necessary to model complex attribute interactions to obtain good classification accuracy on practical problems. In this article, we propose to exploit this phenomenon in the data stream context by building an ensemble of Hoeffding trees that are each limited to a small subset of attributes. In this way, each tree is restricted to model interactions between attributes in its corresponding subset. Because it is not known a priori which attribute subsets are relevant for prediction, we build exhaustive ensembles that consider all possible attribute subsets of a given size. As the resulting Hoeffding trees are not all equally important, we weigh them in a suitable manner to obtain accurate classifications. This is done by combining the log-odds of their probability estimates using sigmoid perceptrons, with one perceptron per class. We propose a mechanism for setting the perceptrons' learning rate using the ADWIN change detection method for data streams, and also use ADWIN to reset ensemble members (i.e., Hoeffding trees) when they no longer perform well. Our experiments show that the resulting ensemble classifier outperforms bagging for data streams in terms of accuracy when both are used in conjunction with adaptive naive Bayes Hoeffding trees, at the expense of runtime and memory consumption. We also show that our stacking method can improve the performance of a bagged ensemble.

year: 2012