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A sugar tax can answer Australia’s obesity problem
Get PDFThis article aims to review literature examining the impact of a sugar-sweetened beverage (SSB) tax in order to make recommendations to the Australian Government about the efficacy of a sugar tax in Australia. Due to Australia’s ageing population and the changed lifestyle of the population in the twenty-first century, chronic diseases have become the largest cause of death in Australia. A significant common risk factor in the four major chronic diseases is obesity. Obesity is caused by a number of factors, some of which are preventable, including nutrition. Thus, strategies that aim to prevent obesity have become a significant area of chronic disease prevention. One such strategy is the introduction of a sugar tax. This article argues that SSB taxes have a positive impact on lowering obesity. A 20 per cent tax on SSBs is the recommendation to the Australian Government, with revenue being used to fund other obesity prevention strategies. Although the government has previously quashed a proposed sugar tax due to belief that the tax would have little positive impact on Australian population, this article indicates that the tax would provide an inexpensive and effective method of addressing obesity prevalence
The relationship between functional trait variation and water availability in hybridising Australian alpine buttercups
Get PDFAustralian alpine buttercup (Ranunculus) species are capable of interspecific hybridisation, yet remain as largely distinct taxonomic entities exhibiting characteristic leaf morphology, growth form, reproductive architecture, phenology, and alpine microhabitat preferences. Past research suggests that interspecific hybrids are morphologically intermediate. If hybrids are also ecologically intermediate, and if the bounded hybrid superiority model holds, then perhaps parent taxa are separated and purified by their habitat preferences. I examined six buttercup taxa and measured soil moisture and leaf traits relevant to water use: area, dissection, shape complexity, specific leaf area, stomatal density, and vascular bundle area. I found no relationship between soil moisture and leaf area, specific leaf area, stomatal density, or vascular bundle area. I found a significant, positive relationship between soil moisture and leaf dissection and shape complexity. These results indicate that other environmental factors, for example temperature or soil salinity, are at play. This was a small study with a limited sample, but nevertheless provides a good starting point for further research on trait variation and hybridisation in Australian alpine buttercups
The effect of UV light intensity on anthocyanin content of Richea continentis leaves
Get PDFThe aim of this study was to determine the effect of UV light intensity on anthocyanin content in Richea continentis leaves. Anthocyanins play an important role in protecting plants from environmental stresses such as high UV exposure and freezing temperatures. This study was conducted because in the context of climate change it is important to understand how increased UV exposure will affect alpine plants. It was hypothesised that anthocyanin content in R. continentis leaves would increase as UV light intensity increases. Three samples of R. continentis were collected from each of four different elevations at Charlotte Pass, NSW, and UV light intensity at these sites was recorded. The leaves’ anthocyanin content was determined using thin layer chromatography and chlorophyll fluorescence (Fv/Fm) was measured as an indicator of leaf stress using a Plant Efficiency Analyser. There was a significant positive correlation between UV light intensity and anthocyanin content, and a significant negative correlation between Fv/Fm and anthocyanin content. No significant correlation was found between light intensity and Fv/Fm, suggesting that anthocyanins act to reduce UV damage in R. continentis leaves
Assessing biomechanical durability of alpine and subalpine leaves via measuring bend and fracture attributes
Get PDFEnvironmental factors, such as dynamic forces and herbivory, place pressure on plants to develop adaptive features in their leaves for resilience against external mechanical forces. Biomechanical traits enable resilience to such pressures. Biomechanical resilience is the physical robustness of a tissue, due to its structure and composition, which affords resilience to mechanical stress. Plants with a low specific leaf area (SLA) are often long-lived, and in low-nutrient environments it can cost more to replace a leaf than to protect it with biomechanical resilience. The alpine and sub-alpine environments are nutrient limited environments, which places stress on plants, limiting their growth. We hypothesised that SLA would be negatively correlated with measures of plant toughness, specifically bend and fracture moduli, in alpine and subalpine leaves. Additionally, we expected leaf thickness to be positively correlated with puncture resilience. We found no relationship between bend modulus and SLA (R2 = 0.140), nor for fracture modulus and SLA (R2 = 0.243). We found no relationship between leaf thickness and fracture modulus; however, the mid-vein fracture modulus was significantly higher than that of the lamina (p < 0.001), which may indicate greater resource investment into vascular tissue via constituent material toughness. Assessing leaf economic strategies of durability and longevity versus less investment and short lifespan can reveal community functional features that occur as a product of environmental pressures. Understanding plant traits that contribute to durability and, by extension, plant longevity, may help to predict how climate change will alter vegetation composition
Field study of endogenous and exogenous contributions to diurnal stomatal conductance rhythms in Eucalyptus pauciflora saplings
Get PDFInternal circadian rhythms and exogenous factors such as light intensity, vapour pressure deficit (VPD) and wind speed affect diurnal cycles of photosynthetic capacity and gas exchange in plants. Stomatal conductance of Eucalyptus pauciflora Sieber ex Spreng saplings was monitored in leaves both in situ and excised in a darkroom for 24–48 hours. We tested for evidence of endogenous rhythms by examining the change in stomatal conductance with the microclimate variables photosynthetic photon flux density (PPFD), VPD and wind speed. In situ, saplings showed clear diurnal cycles of stomatal conductance and increased stomatal conductance pre-dawn on only one of the two measurement mornings. Leaves placed in continuous darkness took over four hours to decrease stomatal conductance to night-time levels and failed to increase stomatal conductance for the next natural photoperiod. Variation in stomatal conductance was found to have a high correlation with light intensity variation (R2 = 0.6736), but low correlation with VPD and wind speed (R2 = 0.0116 & R2 = 0.1694). Our results conflict on whether stomatal conductance is regulated by circadian rhythms in E. pauciflora, however it is possible that with a longer study and more replicates that circadian regulation would be confirmed
Jump distance of Monistria concinna in relation to metabolic rate and femur length:mass ratio
Get PDFMonistria concinna is an abundant grasshopper species from Kosciuszko National Park (KNP). Monistria concinna’s performance levels can be influenced by both morphology and physiology, which can in turn influence KNP’s ecosystem. We studied the effects of femur length:mass ratio (morphology) and metabolic rate (physiology) of M. concinna on jump distances. Jump distance was used as a proxy for performance levels, and there were two treatments used to compare temperatures – ambient temperature and cold temperature. Femur length:mass ratio was not correlated with jump performance, irrespective of temperature. However, the difference in the metabolic rate of the grasshoppers in these treatments approached statistical significance, and grasshoppers in the ambient temperature treatment jumped further than in the cold treatment. Sexual dimorphism was observed. Males had greater femur length:mass ratios and higher mass-specific jumping abilities, but males and females had equivalent jumping abilities. At the time of the experiment, there had been no previous studies on the factors which affect jump distance in M. concinna, though our results indicate that M. concinna may perform better in warming climates
Prosecuting elderly genocidaires: Why we should not reward the evasion of criminal Justice
Get PDFIn recent years, individuals in their 80s and 90s have been put before courts for their role in the Holocaust. Some now argue such legal proceedings are a waste of time, as the punishment available cannot match the crimes of genocide that are alleged, that the accused are too old to imprison. This paper explores the role of the trials of elderly genocidaires in contemporary society and whether it is just to punish these perpetrators. This paper examines the traditional theoretical framework applied to criminal punishment (protection, rehabilitation, deterrence and retribution), and whether or not these pillars remain relevant. The more modern theories of restorative justice and catharsis and the role of victims are then considered. This paper argues that these trials should continue to occur due to the important role they play in general deterrence of war crimes, punitive theories of retribution and the restorative benefit they have for survivors and their families
‘We make angels’: Rediscovering the Victorian ‘Angel in the House’ in Spike Jonze’s Her (2013) and Denis Villeneuve’s Blade Runner 2049 (2017)
Get PDFSpike Jonze’s 2013 film Her and Denis Villeneuve’s 2017 film Blade Runner 2049 (BR2049) both present spectral female characters who, despite being wholly constructed by futuristic technology, echo the Victorian image of the ‘Angel in the House’. Just as male-engineered changes in technology altered women’s roles and responsibilities in the Victorian period, both Her and BR2049 show the software of their respective female characters to be designed by men. Just as the Victorian ‘Angel’ was perceived as belonging to the domestic sphere, yet denied ownership of property, the technological women of Her and BR2049 are shown to be literally contained within masculine structures, with little personal autonomy. The technologically constructed women are also shown to possess a diminished corporeality, which echoes Victorian conceptions of ideal womanhood as spectral and omnipresent. Lastly, like the ideal Victorian ‘Angel’, both technological women are shown to exert an ameliorative moral influence over their respective male partners. While they present speculative visions of futuristic societies, both Her and BR2049 paradoxically engage with Victorian ideas of the Angel in the House, suggesting an iterated pattern of female experience related to rapid technological change
Unrepresentative swill? An unabashed defence of the Australian Senate
Get PDFThis paper argues against the abolition of the Australian Senate. The Senate has endured decades of harsh criticism, exemplified by Paul Keating’s label of ‘unrepresentative swill’. Yet the institution continues to serve a number of useful purposes. Firstly, it enforces the strict horizontal separation of powers enshrined in the Constitution. Secondly, it serves as a state’s house. That is, the Senate protects the rights of less populous states from the tyranny of the majority. In doing so, the chamber upholds Australia’s federalist system. Finally, the Senate functions as a house of review to scrutinise hurried or reckless legislation in an auxiliary capacity. This paper concedes that the Senate in its current form is a flawed institution. As such, two packages of reforms are proposed. Firstly, senatorial terms may be reformed in order to reduce the incidence of rubber-stamping of legislation. Secondly, new states may be formed to reduce the population inequalities of Senate electorates while upholding the federalist system
Gas exchange in Ranunculus species and the evolution of alpine herbaceous plant physiology
Get PDFButtercup species (Ranunculus) in the Australian Alps vary in their leaf morphology and soil moisture preference, but little is known about their rates of gas exchange. Gas exchange rates of three buttercup species, R. graniticola, R. muelleri and R. dissectifolius, were measured under three conditions (ambient CO2, unlimited CO2 (to test maximum photosynthetic rate) and decreased water vapour (to test rates under water stress)) using an infrared gas analyser. There was no statistically significant variation in gas exchange rates between any of the species for any of the conditions. This then begs the question of why morphology has undergone such clear divergent evolution while physiology has not. This paper argues that every morphological ‘decision’ a plant makes has trade-offs and the result of this is the existence of many optimal morphologies that are advantageous in different ways. However, because physiology can change instantaneously to optimise plant growth in different environmental conditions, it does not face the same sort of trade-offs and thereby, plants have fewer options for diverse advantageous physiologies