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The study of immigrant population change is hindered by data sources that capture international migration flows separately from other demographic process and population stock data. In this paper, we illustrate this by gathering detailed demographic data and estimates for the Australia-born population and 18 immigrant populations in Australia, according to their country or region of birth. We then develop a methodology for reconciling differences in these data sets to study the sources of quinquennial immigrant population change from 1981 to 2016 by age, sex, and geographic area. Reconciliation refers to the process of ensuring consistency between the demographic components of change (i.e., births, deaths and migration) and total population change. We validate the methodology by how well it predicts the population 5 years later by age and sex using a multiregional cohort-component prediction model. Once the data are reconciled for every 5-year period from 1981 to 2016, we then see how well the reconciled data reproduces the 2016 population data using the 1981 population as a starting point. This research is useful for improving our understanding of the mechanisms and subsequent spatial contributions of immigration to population change over time. We demonstrate such value by examining the reconciled sources of regional population change for populations born in Australia, the United Kingdom and China over time.

The size and composition of the Australian population has shifted since the dismantling of the discriminatory White Australia Policy during the 1970s, yet its immigration system and border control remain highly regulated. Despite this, detailed information about the specific locations that immigrants arrive to or depart from within Australia are not available. The picture is further compounded by inconsistencies in the measurement of flows and geographic boundaries over time. To address these issues, we obtained available immigration and emigration flow data provided by the Australian Bureau of Statistics at the state and territory level, and developed methods to harmonise the available data, estimate missing elements and disaggregate to a sub-state geography. The methods are applied to 19 birthplace-specific populations across 47 areas in Australia for annual time periods from 1981 to 2016. This research addresses the need for more detailed estimates of demographic events so that a better understanding of the mechanisms and differences underlying regional population change may be provided.

In this chapter, we show how multiplicative components that capture the underlying structures of migration flow tables can be used to inform forecasts of interstate migration in Australia. For our illustration, we decompose 5-year census migration flow tables by state or territory of origin, state or territory of destination, 5-year age group and sex for seven census time periods from 1981–1986 to 2011–2016. The components are described over time and then fitted with time series models to produce holdout sample forecasts of interstate migration with measures of uncertainty. Goodness-of-fit statistics and calibration are then used to identify the best fitting models. The results of this research provide (i) insights into the different migration patterns of an important aspect of subnational population growth in Australia and (ii) potential inputs for standard or multiregional cohort component projection models.

The detrimental effects of oxidative stress and chronic neuroinflammation on neuronal cell death have been implicated in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD) and Parkinson's disease (PD). The nutritional neuroscience is quickly growing, and phytochemicals or phytobioactive compounds such as curcumin, resveratrol, propolis, ginsenoside, and ω-3 polyunsaturated fatty acids (PUFAs) have been extensively applied to potential therapeutic purposes for numerous neurodegenerative diseases for their anti-oxidative and anti-inflammatory effects. However, their administration as food supplements in the daily diet of the elderly is normally a voluntary and less-organized behavior, indicating the uncertainty of therapeutic effects in this sporadic population; specifically, the effective physiological dosages and the real positive effects in preserving brain health have not yet been fully elucidated. In this review, we collect several lines of evidence on these compounds, which constitute a major type of nutraceuticals and are widely integrated into the daily anti-aging caring of elderly patients, and discuss the underlying anti-oxidative and anti-inflammatory mechanisms of these phytochemicals. In conclusion, we highlight the implications of these compounds in the prevention and treatment of geriatric diseases, and of the potential supplementation procedures used as a dietary therapeutic program in clinical nursing services for patients with neurodegenerative diseases or for the elderly in certain communities, which we hope will lead to more beneficial health outcomes with respect to brain function, innate immunity, and gastrointestinal function, as well as more economic and social benefits.