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"All you can heat? Welfare implications of high fixed charge tariffs for electricity"
No full textThis research investigates the implications of residential electricity tariffs with high daily fixed charge or fixed-like components, like ‘all you can eat’ or ‘uncapped’ tariffs which are common for access to internet services. The objective and contributions of the research are: to improve the state of knowledge about household electricity demand in New Zealand; estimate household expenditure systems using methods that are novel in New Zealand; and to provide evidence on tariffs that are likely to be welfare improving. Models of household expenditure are estimated and they show household electricity demand to be highly responsive to changes in average electricity prices, in contradiction of conventional wisdom that electricity demand is price inelastic. A counterfactual price experiment shows a substantial gain in efficiency and an improvement in social welfare from electricity tariffs with high fixed charge components as opposed to the status quo where high variable charges act as a tax on electricity consumption. High fixed charges are shown to be progressive, contradicting concerns that high fixed charges would exacerbate inequality. Smaller households, typically older households, would likely be worse off from high fixed charges, but not substantially or universally so
High and increasing rates of skin infection hospitalisation for Pacific children in Aotearoa
No full textBackground:
Skin and subcutaneous tissue infections are common among children, and are typically bacterial in origin (e.g. impetigo, cellulitis, and skin abscesses which can be caused by Staphylococcus aureus or Streptococcus pyogenes). Hospitalisations are potentially avoidable through good primary care.
Rates of childhood skin infections in Aotearoa are the highest amongst Western countries , and high risk of hospitalisation for Māori and Pacific children and children living in areas of high socioeconomic deprivation. The hospitalisation rates of skin infections in Aotearoa has been gradually increasing, most notably for Pacific children. The study outlines the epidemiology of Pacific children hospitalised with skin infections.
Methods:
This study undertook a retrospective analysis of acute and arranged hospitalisations of children aged 0–14 years with a primary diagnosis of serious skin infection (ICD-10-AM L00–L08, H00.0, H01.0, J34.0, L98.0) from 2000 to 2018.
Results:
The hospitalisation rate for children aged under-15 years with a skin infection increased by 19% from 3.0 per 1,000 in 2000 to 3.5 in 2018. For Pacific children, rates increased significantly (by 36%) from 6.7 per 1,000 in 2000 to 9.2 in 2018. Within the Pacific children hospitalised for skin infections, under-5 year olds have had rates consistently higher than those aged 5–9 and 10–14 years, however, hospitalisation rates have increased significantly for these older age groups. Over 80% of skin infection hospitalisations of Pacific children were for ‘cutaneous abscess, furuncle and carbuncle’ or for cellulitis. Hospitalisation rates for these conditions have increased since 2000, particularly for cellulitis.
Conclusion:
Given the high hospitalisation rate for Pacific children with skin infections, and the increasing rates of hospitalisation for 5–14 year olds, an effective strategy to promote targeted community-level prevention of skin infections and early access to treatment in primary care is recommended for reducing skin infection-associated hospitalisations.Peer Reviewe
New Zealand Deprivation Index 2018 - TA73: Southland District
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
An old drug with new tricks; examining the anti-cancer potential of metformin in mouse and cell models of EML4- ALK+ non-small cell lung cancer
No full textLung cancer is an aggressive disease producing the highest cancer worldwide. Non-small cell lung cancer (NSCLC) accounts for the majority of all lung cancer cases. The discovery of oncogenic receptor tyrosine kinases (RTKs) has led to the development of targeted drugs, improving the survival of many patients. One such RTK occurs when a chromosomal rearrangement fuses the echinoderm microtubule-associated protein-like 4 (EML4) with the anaplastic lymphoma kinase receptor (ALK) producing the constitutively active EML4-ALK. Crizotinib is a first-generation tyrosine kinase inhibitor (TKI) which targets ALK fusions, preventing cancer cell growth, and increasing the progression free survival of patients. However, the effect of crizotinib and other TKIs is limited by the development of acquired resistance. To overcome this, various strategies are being explored, including repurposing existing drugs which may possess anti-cancer mechanisms. Metformin, a hypoglycaemic agent, has promising epidemiological evidence in reducing the risk of several cancers. This thesis aimed to examine if metformin is active against EML4-ALK+ lung cancer and if it provides synergistic benefit to crizotinib.
The first section of this thesis examines if a combination of metformin and crizotinib produces toxicity, which was followed by an in vivo xenograft model study. The drugs in combination showed no liver or kidney toxicity. Metformin did not affect CYP3A activity or polypeptide levels, the main metabolising enzyme of crizotinib. Crizotinib, metformin and the combination slowed the tumour growth rate in an EML4-ALK+ lung cancer xenograft model. However, the combination was not significantly different to the drugs alone and therefore, the combination was not examined further.
The second section of this thesis explored the potential anti-cancer effect of metformin by examining known targets using in vitro techniques. Metformin did not inhibit ALK phosphorylation in EML4-ALK+ cells, confirming that it has a different mechanism of action to that of crizotinib. Nor did metformin affect mTOR or AMPK, however, it did induce apoptosis and a G1 phase cell cycle arrest. Interestingly the mitochondrial membrane potential (Δψm) was reduced with metformin treatment, indicating that metformin is likely inducing mitochondrial dysfunction in cancer cells. An analogue of metformin, mito-metformin10, was shown to be far more cytotoxic and also reduced the Δψm at concentrations far less than that of metformin. To examine if crizotinib was limiting the entry of metformin into the cell, mass spectrometry was conducted. However, this experiment could not conclude whether the
intracellular levels of metformin were reduced with crizotinib treatment, as the within experimental group variation was greater than that of the between group variation.
This thesis demonstrated that metformin can produce anti-cancer effects in EML4-ALK+ lung cancer. Further experimentation should be conducted to confirm the new proposed hypothesis that metformin induces energetic stress in cancer cells due to an inhibition of mitochondrial complex I and reducing hepatogluconeogenesis, preventing glycolysis-induced ATP production. Nevertheless, this thesis supports the hypothesis that metformin may be a beneficial anti-cancer compound in EML4-ALK+ lung cancer
Deformation processes and rheology of the lithospheric mantle under Zealandia: a case study of samples from the Dun Mountain Ophiolite Belt and Otago ultramafic xenoliths, South Island, New Zealand
No full textPeridotitic xenoliths in Cenozoic volcanic rocks around Otago and the Dun Mountain Ophiolite in the South Island of New Zealand offer a window into the lithospheric mantle beneath the Zealandia continent. We selected peridotites from the Red Hills Massif, Dun Mountain Ophiolite, and mantle xenoliths from East and West Otago areas to reconstruct their microstructural evolution.
Oriented sample “pairs” of harzburgite and dunite from a small area (1 km2) are of the Red Hills Massif (Ellis Stream Complex) contain five of the six most common types of olivine crystallographic preferred orientations (CPO; A, C-E and AG except B-type). In each pair, the dunite has a larger grain size and a stronger CPO than the harzburgite. The CPO type in the dunite is different to that in the harzburgite in each pair. Across the area there is an increase in CPO strength from east to west. The secondary dominant orthopyroxene in harzburgite inhibits both olivine grain size coarsening and CPO development. Similarly spinel content in dunite corresponds to local variations in grain size and CPO. Variations across the area relate to a gradient in strain and/or deformation kinematics.
Mantle xenoliths from both East and West Otago areas have no clear foliation and lineation to use as a CPO reference frame. We use the most typical orthopyroxene (100) [001] CPO as a reference frame. Each of the CPOs is rotated so that orthopyroxene (100) is oriented as foliation and [001] as lineation. This enables better inter-comparison of CPOs among xenoliths.
East Otago samples have coarse average olivine grain size (565-800 μm). Olivine CPOs have concentrated [100]OL and [010]OL, and the [100]OL is (sub)parallel to [001]OPX (i.e., coherent olivine and orthopyroxene CPOs). We infer that these CPOs are generated by dislocation creep at high temperature (~1000-1100 °C) and probably with melt present. The differential stresses calculated by using a subgrain piezometer are 3-6 MPa. Harzburgites have similar orthopyroxene and clinopyroxene CPOs while lherzolites do not, probably because clinopyroxene in harzburgite is generated by carbonate metasomatism from orthopyroxene and the new-generated clinopyroxene inherits the orthopyroxene CPO. Clinopyroxene lamellae in orthopyroxene are straight are not strongly deformed, suggesting that major deformation occurred before Cenozoic cooling prior to Alpine Fault initiation.
The samples from West Otago are more complicated. Mantle xenoliths are divided into coarse-grained and protomylonitic harzburgites. In coarse-grained samples, CPO types change from a range of CPOs to dominant axial-[100] (maxima in [100], girdles in [010] and [001]) type, with grain size increasing. Olivine and orthopyroxene Mg# and spinel Cr# are higher and orthopyroxene Al2O3%) lower in coarser samples. Plotting olivine and orthopyroxene grain sizes on a Zener parameter figure is consistent with ~1000 ℃ recrystallisation temperature. Olivine and orthopyroxene CPOs are mostly incoherent, which might relate to melt percolation. Protomylonites have much finer grain size, generated by subgrain rotation (SGR) during dislocation creep. Four-grain junctions and weaker CPOs are used to infer operation of grain boundary sliding in the protomylonites. Olivine CPOs are all [010] clustered and mostly incoherent with orthopyroxene CPOs. The deformation temperature is around ~800 ℃, with estimated ~10-12 s-1 strain rates. Where samples contain remnant coarse grains the CPOs of coarse-grained and protomylonitic material do not align, suggesting that they developed in different episodes with different kinematics. The protomylonites are interpreted as the result of the Alpine Fault movement.
Seismic parameters calculated from CPO data shows that individual coarse-grained samples from East Otago have higher seismic anisotropies than those from West Otago (at both ambient and in-situ conditions), due to higher olivine content. Protomylonitic samples have the lowest seismic anisotropies. The seismic properties of each sample suite are averaged to compare with present day geophysical measurements. As the olivine CPOs and orthopyroxene CPOs are coherent in East Otago the average properties do not depend on a choice of reference frame for samples. In contrast, West Otago xenoliths have incoherent CPOs and choice of reference frame for averaging makes a significant difference. The East Otago seismic data fit current geophysical data well. To fit well, West Otago data must use the orthopyroxene CPO reference frame.
The seismic anisotropy data allow speculation about the large-scale mantle structures in the Lithosphere beneath Otago. To explain the seismic data, olivine [100] needs to be sub-horizontal and parallel to NNW-SSE fast polarization directions with [010] sub-horizontal and perpendicular to these directions. This is consistent with the East Otago lithospheric mantle containing a fossil vertical shear zone with NNW-SSE strike slip motion. The West Otago data is more complicated and requires a range of differently orientated deformation zones
A Comparative Analysis of Emotion Recognition: Young Versus Older Adults Across Gender and Cultures
No full textThe purpose of this research was to investigate emotion recognition in adults across age, gender and culture. Using the six basic emotions of anger, disgust, fear, happiness, sadness, and surprise as stimuli, the aim is to examine whether men and women benefit differently from eye and mouth gazing. Comparisons will be made, first, between male and female participants, second, between young and older adults and third, between Europeans and South-east Asian Chinese. The dependent measure will be correct responses to emotion recognition items. Six basic emotions were shown to 108 young adults (M20 years) and 109 older adults (M70 years) from European and Asian Chinese descent. The two-part experiment which consisted of a web-based survey and the use of an eye-tracker, was conducted in New Zealand (NZ) and Singapore (SG) with facilities provided by the Psychology departments of the University of Otago and the National University of Singapore respectively. I found age-related deficits across cultures and disparity in emotion recognition with NZ Europeans participants outperforming their south-east Asian Chinese counterparts in all emotion recognition tasks. While older women benefitted more from nose gazing, older men’s mouth gazing was associated with worse emotion recognition. In addition, higher depression and loneliness, and lower well-being correlated with worse emotion recognition for younger adults
NZDep2018 analysis of census 2018 variables - DHB02: Waitemata
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
NZDep2018 analysis of census 2018 variables - DHB03: Auckland
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/
NZDep2018 analysis of census 2018 variables - TA030: Hastings District
No full textFor further information about data sources, interpretation of the graphs, and cautions, please see the separate Introduction Chapter
All data relating to the 2018 census is provided by Stats NZ, https://www.stats.govt.nz/