Markov models of aging: theory and practice

We review and structure some of the mathematical and statistical models that have been developed over the past half century to grapple with theoretical and experimental questions about the stochastic development of aging over the life course. We suggest that the mathematical models are in large part addressing the problem of partitioning the randomness in aging: How does aging vary between individuals, and within an individual over the lifecourse? How much of the variation is inherently related to some qualities of the individual, and how much is entirely random? How much of the randomness is cumulative, and how much is merely short-term flutter? We propose that recent lines of statistical inquiry in survival analysis could usefully grapple with these questions, all the more so if they were more explicitly linked to the relevant mathematical and biological models of aging. To this end, we describe points of contact among the various lines of mathematical and statistical research. We suggest some directions for future work, including the exploration of information-theoretic measures for evaluating components of stochastic models as the basis for analyzing experiments and anchoring theoretical discussions of aging.

Integrating science into humanitarian and development planning and practice to enhance community resilience

There has been an increased emphasis upon the application of science for humanitarian and development planning, decision-making and practice; particularly in the context of understanding, assessing and anticipating risk (e.g. HERR, 2011). However, there remains very little guidance for practitioners on how to integrate sciences they may have had little contact with in the past (e.g. climate). This has led to confusion as to which ‘science’ might be of use and how it would be best utilised. Furthermore, since this integration has stemmed from a need to be more predictive, agencies are struggling with the problems associated with uncertainty and probability. Whilst a range of expertise is required to build resilience, these guidelines focus solely upon the relevant data, information, knowledge, methods, principles and perspective which scientists can provide, that typically lie outside of current humanitarian and development approaches. Using checklists, real-life case studies and scenarios the full guidelines take practitioners through a five step approach to finding, understanding and applying science. This document provides a short summary of the five steps and some key lessons for integrating science.

Design and baseline characteristics of the Food4Me study: a web-based randomised controlled trial of personalised nutrition in seven European countries

Improving lifestyle behaviours has considerable potential for reducing the global burden of non-communicable diseases, promoting better health across the life-course and increasing well-being. However, realising this potential will require the development, testing and implementation of much more effective behaviour change interventions than are used conventionally. Therefore, the aim of this study was to conduct a multi-centre, web-based, proof-of-principle study of personalised nutrition (PN) to determine whether providing more personalised dietary advice leads to greater improvements in eating patterns and health outcomes compared to conventional population-based advice. A total of 5,562 volunteers were screened across seven European countries; the first 1,607 participants who fulfilled the inclusion criteria were recruited into the trial. Participants were randomly assigned to one of the following intervention groups for a 6-month period: Level 0-control group-receiving conventional, non-PN advice; Level 1-receiving PN advice based on dietary intake data alone; Level 2-receiving PN advice based on dietary intake and phenotypic data; and Level 3-receiving PN advice based on dietary intake, phenotypic and genotypic data. A total of 1,607 participants had a mean age of 39.8 years (ranging from 18 to 79 years). Of these participants, 60.9 % were women and 96.7 % were from white-European background. The mean BMI for all randomised participants was 25.5 kg m(-2), and 44.8 % of the participants had a BMI ≥ 25.0 kg m(-2). Food4Me is the first large multi-centre RCT of web-based PN. The main outcomes from the Food4Me study will be submitted for publication during 2015.

Higher education engagement in leadership development: using autobiographical narrative to understand potential impact

The paper explores the lived experience of leadership learning and development in a single case study of an entrepreneur participating in a major leadership development programme for owner-managers of Small and Medium Sized Enterprises (SMEs). Based on autobiographical research, it provides a rich contextual account of the nature and underlying influences of leadership learning throughout the life-course, and as a consequence of participation in the programme. Whilst the paper should interest scholars, policy makers, and those concerned with programme development, it may also resonate with entrepreneurs and help them make sense of their experience of leadership development.

How employees remain happy: explaining a paradox

This paper draws on subjective quality of life theory to explain findings from three studies of quality of work life. The studies were conducted with 346 regional process workers, metropolitan employment officers and nurses, The results support the adoption of the theory of homeostasis as an explanation for findings on subjective wellbeing at work surveys. This research goes some way in explaining the paradox that perceived job and work satisfaction remain stable over time, while working conditions may vary widely

Complexities in the career-family perspectives of young professionals

Work-life balance issues are not a constant but are framed differently at different stages of the life-course. In addition to analysing behaviour, it is also important to develop an understanding of the meaning that actors attach to what they do. This article examines the perspectives of young Australian professionals on career, relationships and family. Work-life balance issues are not a constant but are framed differently at different stages of the life-course. In addition to analysing behaviour, it is also important to develop an understanding of the meaning that actors attach to what they do. This article examines the perspectives of young Australian professionals on career, relationships and family formation as these evolve over the early years after university graduation. It provides an insight into their views about the balance between their career goals and family in the early years of their professional working lives. It reports a longitudinal study of 86 young Australian professionals from 1997 to 2003, which highlights the emergent and contingent nature of decisions about careers and relationships and their relevance for childbearing. Gender plays a role in their plans and expectations but they reject the traditional male breadwinner model. The high value given to dual career relationships may put stress on their ability to balance family aspirations with satisfactory careers.yformation as these evolve over the early years after university graduation. It provides an insight into their views about the balance between their career goals and family in the early years of their professional working lives. It reports a longitudinal study of 86young Australian professionalsfrom 1997 to 2003, which highlights the emergent and contingent nature of decisions about careers and relationships andtheir relevancefor childbearing. Gender plays a role in their plans and expectations but they reject the traditional male breadwinner model. The high value given to dual career relationships may put stress on their ability to balance family aspirations with satisfactory careers.

Older Australians : involvement in civil society in the 1990s

As Australia’s population continues to age, questions about how older individuals use their time holds increasing interest and significance for scholars and policy makers. As individuals near the end of their paid working life, and family roles and responsibilities diminish, the type of activities that will fill this time void have important implications for the health and wellbeing of older Australians and for the strength of civil society. In Australia, there have been sustained moves at all levels of government to encourage the more active engagement in community services of this group of citizens, given the size and significant amount of human capital of this cohort. However, international research suggests that this enthusiasm has not translated into increased volunteer activity for seniors, and that older citizens tend to spend their expanding discretionary time pursuing leisure activities, such as watching television or listening to the radio (Robinson & Godbey 1997; Wilson & Musick 1997; Thoits & Hewitt 2001). This study builds on a broader interest in how people choose to utilise time across the life course and how the experience of ageing shapes such decisions. This aim of this paper is twofold – first, to investigate how older Australians allocated their time in the 1990s, and how these time use patterns changed over a 5-year period, using nationally representative, longitudinal data from two waves of the Australian Time Use Survey. Second, the time use characteristics of those individuals who devote more time to social participation activities are examined, to investigate trends in volunteering across age cohorts, with a focus on those above the age of fifty.

Long-term reproductive success of Australasian gannets (Morus serrator)

Life history theory predicts that individuals make trade-offs between investment in current reproduction, future reproductive potential and success in order to maximise lifetime reproductive success (LRS). Factors that may influence LRS in seabirds include delayed maturity, small clutches, high adults survivorship and long life spans. Studies have shown that reproductive success of seabirds increases with age and experience. Australasian gannets are long-lived seabirds that typically commence breeding at five or six years of age. A small colony of gannets was monitored over 12 years. This study aimed to identify patterns of long-term individual breeding biology. Results indicate that nest site, pair bond duration, age and breeding experience are all important factors in reproductive success. Relationships were found between breeding success and several variables including breeding experience, pair bond duration and nest site quality. Identifying and understanding the factors that contribute to individuals’ reproductive success is of critical importance for future conservation and management of seabird species.

Markers of inflammation in South Asian and European infants from birth to 2 years in Manchester, UK

Inflammatory markers, including serum C-reactive protein (CRP), are predictors of coronary heart disease (CHD) in adults. South Asians in the UK have higher rates of CHD in adulthood than national rates.We tested the hypotheses that South Asian infants would have higher serum concentrations of CRP and homocysteine than European infants up to 2 years of age and that higher infant weight is associated with elevation of inflammatory markers. Infants of South Asian and European origin were investigated in a mixed cross sectional-longitudinal cohort study. Mothers were recruited ante-natally from St Mary’s Hospital,Manchester by postal invitation and telephone call to non-responders. Infants with metabolic or congenital abnormalities, known syndromes or pre-maturity were excluded. Measurements were collected at birth and either 3, 6, 12 or 24 months. High sensitivity CRP and homocysteine were measured by an immulite immunoassay. We used mixed linear modelling to assess whether infant weight, ethnicity, length of follow-up or their interaction were associated with inflammatory makers in infants during follow-up. Data are presented on 306 infants (109 South Asian and 197 European). We found that European infants had higher serum CRP than South Asian infants during follow-up which was of borderline significance.There was no difference in serum homocysteine between ethnic groups during followup and no significant interaction between ethnicity and follow-up. Infant weight was significantly associated with CRP but not homocysteine. In this ongoing longitudinal study,we found little difference in inflammatory markers in infants from birth to 2 years despite markedly higher rates of CHD in South Asian than European adults. Life course exposure to risk factors may play a more dominant role in the development of CHD.

Occupational and non-occupational physical activity and the social determinants of physical activity : results from the Health Survey for England

Background: This article aims to examine the relative contribution of occupational activity to English adults’ meeting of government recommendations for physical activity (PA).

Methods: Data were extracted from a cross-sectional survey of householders in the UK via the Health Survey for England.¹ In total, 14,018 adult participants were included in the analysis. Multivariate logistic regression was used to examine the odds of achieving PA recommendations with and without including occupational activity and to examine the contribution of gender and social and demographic characteristics.

Results: When occupational PA was included, 36% of men and 25% of women were active at the recommended level. Once occupational PA was removed, these proportions were 23% and 19%, respectively. These results were socially patterned, most notably by age and gender.

Conclusions: Occupational PA provides a substantial contribution to those meeting the government target for PA.

Psychic resonance of the pre-Oedipal mother

Few would deny the importance of the mother in the care of her infant, but her relevance, her resonance and the indelible traces she leaves in the psyche of the developing individual and which thereafter accompanies and influences the life course is investigated in this psychoanalytically informed study.

3D leadership for national renewal

A perpetual immigrant, Professor Frederick relates his life course that brought him to New Zealand and describes what he found here. One of the country’s early advocates of the “knowledge economy” path to economic development, Frederick outlines his vision of leadership for the new millennium that will help restore New Zealand to the top half of the OECD and grow the cake for the prosperity of all. He relates what we expect from our leaders as well as his personal vision to leadership in New Zealand.

The Early Prevention of Obesity in CHildren (EPOCH) collaboration : an individual patient data prospective meta-analysis

Background
Efforts to prevent the development of overweight and obesity have increasingly focused early in the life course as we recognise that both metabolic and behavioural patterns are often established within the first few years of life. Randomised controlled trials (RCTs) of interventions are even more powerful when, with forethought, they are synthesised into an individual patient data (IPD) prospective meta-analysis (PMA). An IPD PMA is a unique research design where several trials are identified for inclusion in an analysis before any of the individual trial results become known and the data are provided for each randomised patient. This methodology minimises the publication and selection bias often associated with a retrospective meta-analysis by allowing hypotheses, analysis methods and selection criteria to be specified a priori.

Methods/Design
The Early Prevention of Obesity in CHildren (EPOCH) Collaboration was formed in 2009. The main objective of the EPOCH Collaboration is to determine if early intervention for childhood obesity impacts on body mass index (BMI) z scores at age 18-24 months. Additional research questions will focus on whether early intervention has an impact on children's dietary quality, TV viewing time, duration of breastfeeding and parenting styles. This protocol includes the hypotheses, inclusion criteria and outcome measures to be used in the IPD PMA. The sample size of the combined dataset at final outcome assessment (approximately 1800 infants) will allow greater precision when exploring differences in the effect of early intervention with respect to pre-specified participant- and intervention-level characteristics.

Discussion
Finalisation of the data collection procedures and analysis plans will be complete by the end of 2010. Data collection and analysis will occur during 2011-2012 and results should be available by 2013.