title: Stratigraphy and reserves of pumiceous sand deposits in Perry's 'Asparagus Block' at Horotiu

authors: Nelson, Campbell S.

abstract: The stratigraphic relationships between the deposits of the Hinuera Formation and the Taupo Pumice Alluvium are described over a 16 ha plot of land known as the 'Asparagus Block' at Horotiu. The Hinuera Formation is exposed at the surface at the southern end of this block, and is overlain by a wedge of Taupo Pumice Alluvium which increases in thickness from 0 to 8 m northwards across the block. Lithofacies in the Hinuera Formation are dominated by trough cross-bedded gravelly sands (lithofacies AI), with common cross-laminated sands (lithofacies B) and massive to horizontally laminated silts (lithofacies D). The pumice content of these deposits is mainly <10%, but in lithofacies B and D can locally reach >70%. Lithofacies in the Taupo Pumice Alluvium are dominated by horizontally to inclined (tabular cross-) bedded slightly gravelly sands and sands (lithofacies G 1/2), with common occurrences of horizontally bedded to massive sandy silts (lithofacies D). The pumice content of these Taupo deposits is high, typically >80%. Cross-sections are presented showing an interpreted subsurface distribution of these lithofacies from south to north through the 'Asparagus Block'. The estimated reserve of extractable pumice sand from the block is of the order of about 400,000 to 450,000 m³.

text: Stratigraphy and reserves of pumiceous sand deposits in Perry's 'Asparagus Block' at Horotiu The stratigraphic relationships between the deposits of the Hinuera Formation and the Taupo Pumice Alluvium are described over a 16 ha plot of land known as the 'Asparagus Block' at Horotiu. The Hinuera Formation is exposed at the surface at the southern end of this block, and is overlain by a wedge of Taupo Pumice Alluvium which increases in thickness from 0 to 8 m northwards across the block. Lithofacies in the Hinuera Formation are dominated by trough cross-bedded gravelly sands (lithofacies AI), with common cross-laminated sands (lithofacies B) and massive to horizontally laminated silts (lithofacies D). The pumice content of these deposits is mainly <10%, but in lithofacies B and D can locally reach >70%. Lithofacies in the Taupo Pumice Alluvium are dominated by horizontally to inclined (tabular cross-) bedded slightly gravelly sands and sands (lithofacies G 1/2), with common occurrences of horizontally bedded to massive sandy silts (lithofacies D). The pumice content of these Taupo deposits is high, typically >80%. Cross-sections are presented showing an interpreted subsurface distribution of these lithofacies from south to north through the 'Asparagus Block'. The estimated reserve of extractable pumice sand from the block is of the order of about 400,000 to 450,000 m³.

year: 1997

title: Democracy vs. populism: the transformation of politics in Nigeria?

authors: Adeakin, Ibikunle

subjects: neo-liberal military-directed populism

abstract: Since the return of electoral democracy to Nigeria in 1999, two of the four elected presidents have been former military dictators who have stressed anti-corruption and national security policies in populist campaigns. As military dictators in previous years, they had instigated regimes that had practiced stern military discipline; as populists they have leaned toward these two policies. Reactions to civilian corruption and threats to national security have represented the primary military rationales for mil-itary intervention in the past. A popular vote in 2015 for former military dictator Gen- eral Muhammadu Buhari seems to have represented a continuing preference for popu- lism over democracy. We will examine the new populism in Nigeria, complicated as it is by questions of ethnicity, religion and military identity, with a view to explaining the like- ly outcome of the first peaceful transference of power from one political party to anoth- er in Africa’s most populous country.

text: Democracy vs. populism: the transformation of politics in Nigeria? Since the return of electoral democracy to Nigeria in 1999, two of the four elected presidents have been former military dictators who have stressed anti-corruption and national security policies in populist campaigns. As military dictators in previous years, they had instigated regimes that had practiced stern military discipline; as populists they have leaned toward these two policies. Reactions to civilian corruption and threats to national security have represented the primary military rationales for mil-itary intervention in the past. A popular vote in 2015 for former military dictator Gen- eral Muhammadu Buhari seems to have represented a continuing preference for popu- lism over democracy. We will examine the new populism in Nigeria, complicated as it is by questions of ethnicity, religion and military identity, with a view to explaining the like- ly outcome of the first peaceful transference of power from one political party to anoth- er in Africa’s most populous country.

year: 2017

title: Investigation of in vitro diabetic inflammation and  treatment with Piper excelsum tea extract

authors: Harvey, Savannah

subjects: Piper excelsum

abstract: Induction of inflammation through hyperglycaemia and adiposity has been shown to contribute to the pathogenicity of type 2 diabetes (T2D). The pro-inflammatory cytokine, tumour necrosis factor α (TNF-α) was the first cytokine found to bridge the connection between the immune system and T2D. This was found due to its increased production in the disease state. TNF-α has specifically been linked to the onset of insulin resistance in T2D models. Evidence has shown that heat shock protein 60 (HSP60) may also play a role as a danger signal for the immune system as it can result in the induction of inflammation. Currently, there are no pharmaceutical options for T2D patients which target inflammation. Tea made from the leaves of kawakawa (Piper excelsum) has been used for many generations by Māori as a traditional rākau rongoā (traditional medicine) to treat a range of ailments including inflammation. The aim of this project was to investigate the modulation of inflammation using a commercially available kawakawa tea in human cancer cells in vitro. 

This project involved measuring the growth rate, cytotoxicity, TNF-α production and HSP60 expression upon exposure to three treatments: high glucose, lipopolysaccharide (LPS) or kawakawa tea extract (KTE).

This study showed that a high concentration of KTE (1000 µg/mL) inhibited cell growth in both HEPG2 and HeLa cell lines. Cells treated with this concentration also showed typical morphological signs of apoptosis. Cytotoxicity testing confirmed that there was a significant (p <0.05) decrease in mitochondrial dehydrogenase activity for this treatment which confirmed the cells were likely dying through apoptosis. Over a course of 24-hours three LPS treatments were found to be cytotoxic. These were the 10 ng/mL, 10 µg/mL, and 100 µg/mL concentrations of LPS. After 48-hours all treatments apart from 100 µg/mL KTE treatment were also found to be cytotoxic. The cytotoxicity for these treatments was either due to a reduction in mitochondrial dehydrogenase activity (infers mitochondrial stress) or increased lactate dehydrogenase (LDH) release from cells (infers necrotic cell death). These cytotoxicity experiments allowed for identification of which concentrations should be selected or removed for future experiments. 

Cytotoxicity levels were taken into consideration and experiments were run investigating the induction of TNF-α using enzyme-linked immunosorbent assays (ELISA). Issues regarding negative readings from samples arose which resulted in protocol changes and extensive trouble shooting. It was found that extended exposure times were required to attenuate a positive result from the positive control, LPS. 

HSP60 expression was also measured for human cells exposed to high glucose and KTE treatments. No change in HSP60 expression was detected. However, 24-hour LPS exposure resulted in a significant increase in HSP60 expression compared to the control for the 100 ng/mL LPS treatment. Two concentrations were investigated; 100 ng/mL LPS and 100 µg/mL LPS which resulted in 1.4- and 2.1-fold increases compared to the control, respectively.

Overall, no conclusion could be drawn regarding the modulation of inflammation by KTE. However, this study was able to identify the effect the tea has on human cancer cell growth and the nature of cytotoxicity the tea poses to the cells. It is recommended to continue this research exploring different kawakawa tea blends and using alternative in vitro cell lines and whole animal models.

text: Investigation of in vitro diabetic inflammation and  treatment with Piper excelsum tea extract Induction of inflammation through hyperglycaemia and adiposity has been shown to contribute to the pathogenicity of type 2 diabetes (T2D). The pro-inflammatory cytokine, tumour necrosis factor α (TNF-α) was the first cytokine found to bridge the connection between the immune system and T2D. This was found due to its increased production in the disease state. TNF-α has specifically been linked to the onset of insulin resistance in T2D models. Evidence has shown that heat shock protein 60 (HSP60) may also play a role as a danger signal for the immune system as it can result in the induction of inflammation. Currently, there are no pharmaceutical options for T2D patients which target inflammation. Tea made from the leaves of kawakawa (Piper excelsum) has been used for many generations by Māori as a traditional rākau rongoā (traditional medicine) to treat a range of ailments including inflammation. The aim of this project was to investigate the modulation of inflammation using a commercially available kawakawa tea in human cancer cells in vitro. 

This project involved measuring the growth rate, cytotoxicity, TNF-α production and HSP60 expression upon exposure to three treatments: high glucose, lipopolysaccharide (LPS) or kawakawa tea extract (KTE).

This study showed that a high concentration of KTE (1000 µg/mL) inhibited cell growth in both HEPG2 and HeLa cell lines. Cells treated with this concentration also showed typical morphological signs of apoptosis. Cytotoxicity testing confirmed that there was a significant (p <0.05) decrease in mitochondrial dehydrogenase activity for this treatment which confirmed the cells were likely dying through apoptosis. Over a course of 24-hours three LPS treatments were found to be cytotoxic. These were the 10 ng/mL, 10 µg/mL, and 100 µg/mL concentrations of LPS. After 48-hours all treatments apart from 100 µg/mL KTE treatment were also found to be cytotoxic. The cytotoxicity for these treatments was either due to a reduction in mitochondrial dehydrogenase activity (infers mitochondrial stress) or increased lactate dehydrogenase (LDH) release from cells (infers necrotic cell death). These cytotoxicity experiments allowed for identification of which concentrations should be selected or removed for future experiments. 

Cytotoxicity levels were taken into consideration and experiments were run investigating the induction of TNF-α using enzyme-linked immunosorbent assays (ELISA). Issues regarding negative readings from samples arose which resulted in protocol changes and extensive trouble shooting. It was found that extended exposure times were required to attenuate a positive result from the positive control, LPS. 

HSP60 expression was also measured for human cells exposed to high glucose and KTE treatments. No change in HSP60 expression was detected. However, 24-hour LPS exposure resulted in a significant increase in HSP60 expression compared to the control for the 100 ng/mL LPS treatment. Two concentrations were investigated; 100 ng/mL LPS and 100 µg/mL LPS which resulted in 1.4- and 2.1-fold increases compared to the control, respectively.

Overall, no conclusion could be drawn regarding the modulation of inflammation by KTE. However, this study was able to identify the effect the tea has on human cancer cell growth and the nature of cytotoxicity the tea poses to the cells. It is recommended to continue this research exploring different kawakawa tea blends and using alternative in vitro cell lines and whole animal models.

year: 2021