title: Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems

authors: Thrush, Simon F.

subjects: Austrovenus stutchburyi

abstract: Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.

text: Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.

year: 2014

title: The roles of observational astronomy in ancient Greece

authors: Hannah, Robert

abstract: This paper offers an investigation into the interface between science, in the form of astronomy, and culture, in the form of religion and the calendar. Early societies made use of a variety of mechanisms to mark time, based on the cycles of the sun, moon and stars, whether separately or in combination. In this paper I provide a survey of the use of one of these cycles, namely that of the stars, in one ancient culture, that of the Greeks. I show how gradually the night sky was mapped out with a number of distinct constellations, the number increasing over time. The Greeks used the first and last visible risings and settings of these stars at dawn and dusk as ‘event markers’, in order to signal the appropriate time for pivotal activities, especially in the agricultural sphere, such as ploughing, sowing and harvesting. At the same time, Greek societies used the moon as the basis for their civil and religious calendar, and within the lunar months were situated regular festivals of an agricultural nature. Agriculture is tied to the seasons and hence the sun, which the star cycle matches fairly well, but the moon runs on a different cycle which does not keep pace with the sun and stars. The increased refinement of the star calendars with a larger number of constellations might be a result of a desire to help synchronise the divergent seasonal and lunar timetables. Examples are provided to illustrate how particulars stars might have been associated with particular divinities and festivals.

text: The roles of observational astronomy in ancient Greece This paper offers an investigation into the interface between science, in the form of astronomy, and culture, in the form of religion and the calendar. Early societies made use of a variety of mechanisms to mark time, based on the cycles of the sun, moon and stars, whether separately or in combination. In this paper I provide a survey of the use of one of these cycles, namely that of the stars, in one ancient culture, that of the Greeks. I show how gradually the night sky was mapped out with a number of distinct constellations, the number increasing over time. The Greeks used the first and last visible risings and settings of these stars at dawn and dusk as ‘event markers’, in order to signal the appropriate time for pivotal activities, especially in the agricultural sphere, such as ploughing, sowing and harvesting. At the same time, Greek societies used the moon as the basis for their civil and religious calendar, and within the lunar months were situated regular festivals of an agricultural nature. Agriculture is tied to the seasons and hence the sun, which the star cycle matches fairly well, but the moon runs on a different cycle which does not keep pace with the sun and stars. The increased refinement of the star calendars with a larger number of constellations might be a result of a desire to help synchronise the divergent seasonal and lunar timetables. Examples are provided to illustrate how particulars stars might have been associated with particular divinities and festivals.

year: 2015

title: Māori men and the indirect procurement and sharing of prescription medications

authors: Hodgetts, Darrin

subjects: Māori men

abstract: Māori men have higher rates of many diseases and lower life expectancy than other population groups in New Zealand. The general consensus is that these health inequalities are due to the inequitable distribution of the social determinants of health; for example, education, employment, income and housing, and were largely driven by colonization and the social and economic marginalization of Māori. Health care factors, including reluctance to consult doctors or late presentation, are part of this equation, but do not fully explain the disparities in health between Māori men and other population groups. As part of our ongoing work in this area, we draw on a focus group discussion with seven Māori community health workers to provide a preliminary analysis of how some Māori people access and use medications. Particular attention is given to the emergent practice of Māori women presenting to general practitioners (GPs) with proxy symptoms to obtain medications for their male partners. This practice exemplifies a range of strategies that some whānau (family) have developed to navigate the health system and overcome the reluctance of some men to engage with the medical profession. The practice raises issues relating to the nature of “primary” and “whānau” care, accessibility of medical services and medications, adherence to medication regimes and the dynamics of doctor–patient relations.

text: Māori men and the indirect procurement and sharing of prescription medications Māori men have higher rates of many diseases and lower life expectancy than other population groups in New Zealand. The general consensus is that these health inequalities are due to the inequitable distribution of the social determinants of health; for example, education, employment, income and housing, and were largely driven by colonization and the social and economic marginalization of Māori. Health care factors, including reluctance to consult doctors or late presentation, are part of this equation, but do not fully explain the disparities in health between Māori men and other population groups. As part of our ongoing work in this area, we draw on a focus group discussion with seven Māori community health workers to provide a preliminary analysis of how some Māori people access and use medications. Particular attention is given to the emergent practice of Māori women presenting to general practitioners (GPs) with proxy symptoms to obtain medications for their male partners. This practice exemplifies a range of strategies that some whānau (family) have developed to navigate the health system and overcome the reluctance of some men to engage with the medical profession. The practice raises issues relating to the nature of “primary” and “whānau” care, accessibility of medical services and medications, adherence to medication regimes and the dynamics of doctor–patient relations.

year: 2011