Maternal age and paternal age are associated with distinct childhood behavioural outcomes in a general population birth cohort

Abstract Background Recent studies show that advanced paternal age (APA) is associated with an increased risk of neurodevelopmental disorders such as autism, bipolar disorder and schizophrenia. A body of evidence also suggests that individuals who develop schizophrenia show subtle deviations in a range of behavioural domains during their childhood. The aim of the study was to examine the relationship between paternal and maternal ages and selected behavioural measures in children using a large birth cohort. Method Participants were singleton children (n = 21,753) drawn from the US Collaborative Perinatal Project. The outcome measures were assessed at 7 years. The main analyses examined the relationship between parental age and behavioural measures when adjusted for a range of potentially confounding variables, including age of the other parent, maternal race, socio-economic measures, sex, gestation length, maternal marital status, parental mental illness, and child's age-at-testing. Results Advanced paternal age was associated with a significantly increased risk of adverse ‘externalizing’ behaviours at age seven years. For every five year increase in paternal age, the odds of higher ‘externalizing’ behaviours was increased by 12% (OR = 1.12; 95% CI = 1.03, 1.21, p < 0.0001). The relationship persisted after adjusting for potential confounding factors. ‘Internalizing’ behavioural outcome was not associated with advanced paternal age. In contrast, advanced maternal age was significantly protective against adverse ‘externalizing’ behavioural outcomes, but associated with an increased risk of adverse ‘internalizing’ behavioural outcomes. Discussion The offspring of older fathers show a distinctly different pattern of behaviours compared to the offspring of older mothers. The diverse socio-cultural and biologically-mediated factors that underpin these findings remain to be clarified. In light of secular trends related to delayed parenthood, the mechanisms underlying these findings warrant closer scrutiny.

Drivers of adoption for successive generation of high-tech products

To understand the diffusion of high technology products such as PCs, digital cameras and DVD players it is necessary to consider the dynamics of successive generations of technology. From the consumer’s perspective, these technology changes may manifest themselves as either a new generation product substituting for the old (for instance digital cameras) or as multiple generations of a single product (for example PCs). To date, research has been confined to aggregate level sales models. These models consider the demand relationship between one generation of a product and a successor generation. However, they do not give insights into the disaggregate-level decisions by individual households – whether to adopt the newer generation, and if so, when. This paper makes two contributions. It is the first large scale empirical study to collect household data for successive generations of technologies in an effort to understand the drivers of adoption. Second, in contrast to traditional analysis in diffusion research that conceptualizes technology substitution as an “adoption of innovation” type process, we propose that from a consumer’s perspective, technology substitution combines elements of both adoption (adopting the new generation technology) and replacement (replacing generation I product with generation II). Key Propositions In some cases, successive generations are clear “substitutes” for the earlier generation (e.g. PCs Pentium I to II to III ). More commonly the new generation II technology is a “partial substitute” for existing generation I technology (e.g. DVD players and VCRs). Some consumers will purchase generation II products as substitutes for their generation I product, while other consumers will purchase generation II products as additional products to be used as well as their generation I product. We propose that substitute generation II purchases combine elements of both adoption and replacement, but additional generation II purchases are solely adoption-driven process. Moreover, drawing on adoption theory consumer innovativeness is the most important consumer characteristic for adoption timing of new products. Hence, we hypothesize consumer innovativeness to influence the timing of both additional and substitute generation II purchases but to have a stronger impact on additional generation II purchases. We further propose that substitute generation II purchases act partially as a replacement purchase for the generation I product. Thus, we hypothesize that households with older generation I products will make substitute generation II purchases earlier. Methods We employ Cox hazard modeling to study factors influencing the timing of a household’s adoption of generation II products. A separate hazard model is conducted for additional and substitute purchases. The age of the generation I product is calculated based on the most recent household purchase of that product. Control variables include size and income of household, age and education of decision-maker. Results and Implications Our preliminary results confirm both our hypotheses. Consumer innovativeness has a strong influence on both additional purchases and substitute purchases. Also consistent with our hypotheses, the age of the generation I product has a dramatic influence for substitute purchases of VCR/DVD players and a strong influence for PCs/notebooks. Yet, also as hypothesized, there was no influence on additional purchases. This implies that there is a clear distinction between additional and substitute purchases of generation II products, each with different drivers. For substitute purchases, product age is a key driver. Therefore marketers of high technology products can utilize data on generation I product age (e.g. from warranty or loyalty programs) to target customers who are more likely to make a purchase.

Polybrominated diphenyl ether (PBDE) concentrations decrease with age : analysis of pooled human blood serum in the Australian population

Introduction Polybrominated diphenyl ethers (PBDEs) are considered to be a cost effective and efficient way to reduce the possibility of product ignition and inhibit the spread of fire, thereby limiting harm caused by fires. PBDEs are incorporated into a wide variety of manufactured products and are now considered an ubiquitous contaminant found worldwide in biological and environmental samples . In comparison to “traditional” persistent organic pollutants (POPs), the exposure modes of PBDEs in humans are less well defined, although dietary sources, inhalation (air/particulate matter) and dust ingestion have been reported 2-4. Limited investigations of population specific factors such as age or gender and PBDE concentrations report: no conclusive correlation by age in adults ; higher concentrations in children ; similar concentrations in maternal and cord blood ; and no gender differences . After preliminary findings of higher PBDE concentrations in children than in adults in Australia11 we sought to investigate at what age the PBDE concentrations peaked in an effort to focus exposure studies. This investigation involved the collection of blood samples from young age groups and the development of a simple model to predict PBDE concentrations by age in Australia.

The influence of age and gender on triclosan concentrations in Australian human blood serum

The bactericide triclosan has found wide-spread use in e.g. soaps, deodorants and toothpastes. Recent in vitro and in vivo studies indicate that triclosan might exert adverse effects in humans. Triclosan has previously been shown to be present in human plasma and milk at concentrations that are well correlated to the use of personal care products containing triclosan. In this study we investigated the influence of age, gender, and the region of residence on triclosan concentrations in pooled samples of Australian human blood serum. The results showed no influence of region of residence on the concentrations of triclosan. There was a small but significant influence of age and gender on the serum triclosan concentrations, which were higher in males than in females, and highest in the group of 31–45 year old males and females. However, overall there was a lack of pronounced differences in the triclosan concentrations within the dataset, which suggests that the exposure to triclosan among different groups of the Australian population is relatively homogenous. A selection of the dataset was compared with previous measurements of triclosan concentrations in human plasma from Sweden, where the use of triclosan is expected to be low due to consumer advisories. The triclosan concentrations were a factor of 2 higher in Australian serum than in Swedish plasma.

Serum polybrominated diphenyl ethers (PBDE) in pooled serum are higher in children (2-5 years of age) than in infants and adults

Background: Polybrominated diphenyl ethers (PBDEs) are used as flame retardants in many products and have been detected in human samples worldwide. Limited data show that concentrations are elevated in young children. Objectives: We investigated the association between PBDEs and age with an emphasis on young children from Australia in 2006–2007. Methods: We collected human blood serum samples (n = 2,420), which we stratified by age and sex and pooled for analysis of PBDEs. Results: The sum of BDE-47, -99, -100, and -153 concentrations (Σ4PBDE) increased from 0–0.5 years (mean ± SD, 14 ± 3.4 ng/g lipid) to peak at 2.6–3 years (51 ± 36 ng/g lipid; p < 0.001) and then decreased until 31–45 years (9.9 ± 1.6 ng/g lipid). We observed no further significant decrease among ages 31–45, 45–60 (p = 0.964), or > 60 years (p = 0.894). The mean Σ4PBDE concentration in cord blood (24 ± 14 ng/g lipid) did not differ significantly from that in adult serum at ages 15–30 (p = 0.198) or 31–45 years (p = 0.140). We found no temporal trend when we compared the present results with Australian PBDE data from 2002–2005. PBDE concentrations were higher in males than in females; however, this difference reached statistical significance only for BDE-153 (p = 0.05). Conclusions: The observed peak concentration at 2.6–3 years of age is later than the period when breast-feeding is typically ceased. This suggests that in addition to the exposure via human milk, young children have higher exposure to these chemicals and/or a lower capacity to eliminate them. Key words: Australia, children, cord blood, human blood serum, PBDEs, polybrominated diphenyl ethers. Environ Health Perspect 117:1461–1465 (2009). doi:10.1289/ehp.0900596

Innovation

Innovation can be defined broadly to include the development and uptake of new technology, the introduction of new products, the utilisation of new market opportunities and the implementation of new business processes including new forms of work organisation or management structures and approaches. Innovation, or the commercial application of new knowledge, is of increasing importance to economic competitiveness given the growth in production and trade in high technology industries and knowledge intensive service sectors such as business services (Edquist, Hommen and McKelvey 2001). An important field of innovation in modern economies is associated with the rapid development and application of information and communications technologies (ICTs). ICTs constitute an increasing share of value added, growth and employment and also impact on employment and productivity in other industry sectors. The structural transformation of modern economies associated with ICTs has led to an increase in the importance of information and knowledge resources (rather than physical capital) as inputs or factors of production. Technology and product innovations are often given central attention in innovation research, however, organisational and managerial changes have been recognised as critical. Over the last two decades, understandings of the nature and process of innovation have advanced significantly. In the 1950s and 1960s, there was a view that innovation resulted from basic research, or in essence that scientific research acted as a 'push' for innovation. As such there was a great deal of emphasis on formal research and development, undertaken either by governments or research and development units within business organisations. Radical innovations involving new products and new technological trajectories were thought to derive from basic research (Freeman 1995).

Influences of age and mechanical stability on volume, microstructure, and mineralization of the fracture callus during bone healing : Is osteoclast activity the key to age-related impaired healing?

Earlier studies have shown that the influence of fixation stability on bone healing diminishes with advanced age. The goal of this study was to unravel the relationship between mechanical stimulus and age on callus competence at a tissue level. Using 3D in vitro micro-computed tomography derived metrics, 2D in vivo radiography, and histology, we investigated the influences of age and varying fixation stability on callus size, geometry, microstructure, composition, remodeling, and vascularity. Compared were four groups with a 1.5-mm osteotomy gap in the femora of Sprague–Dawley rats: Young rigid (YR), Young semirigid (YSR), Old rigid (OR), Old semirigid (OSR). Hypothesis was that calcified callus microstructure and composition is impaired due to the influence of advanced age, and these individuals would show a reduced response to fixation stabilities. Semirigid fixations resulted in a larger ΔCSA (Callus cross-sectional area) compared to rigid groups. In vitro μCT analysis at 6 weeks postmortem showed callus bridging scores in younger animals to be superior than their older counterparts (pb0.01). Younger animals showed (i) larger callus strut thickness (pb0.001), (ii) lower perforation in struts (pb0.01), and (iii) higher mineralization of callus struts (pb0.001). Callus mineralization was reduced in young animals with semirigid fracture fixation but remained unaffected in the aged group. While stability had an influence, age showed none on callus size and geometry of callus. With no differences observed in relative osteoid areas in the callus ROI, old as well as semirigid fixated animals showed a higher osteoclast count (pb0.05). Blood vessel density was reduced in animals with semirigid fixation (pb0.05). In conclusion, in vivo monitoring indicated delayed callus maturation in aged individuals. Callus bridging and callus competence (microstructure and mineralization) were impaired in individuals with an advanced age. This matched with increased bone resorption due to higher osteoclast numbers. Varying fixator configurations in older individuals did not alter the dominant effect of advanced age on callus tissue mineralization, unlike in their younger counterparts. Age-associated influences appeared independent from stability. This study illustrates the dominating role of osteoclastic activity in age-related impaired healing, while demonstrating the optimization of fixation parameters such as stiffness appeared to be less effective in influencing healing in aged individuals.

GVS : A flexible, low-end, 3D visualisation framework for enhancing conceptual groundwater models for community, management and simulations

In this paper we discuss an advanced, 3D groundwater visualisation and animation system that allows scientists, government agencies and community groups to better understand the groundwater processes that effect community planning and decision-making. The system is unique in that it has been designed to optimise community engagement. Although it incorporates a powerful visualisation engine, this open-source system can be freely distributed and boasts a simple user interface allowing individuals to run and investigate the models on their own PCs and gain intimate knowledge of the groundwater systems. The initial version of the Groundwater Visualisation System (GVS v1.0), was developed from a coastal delta setting (Bundaberg, QLD), and then applied to a basalt catchment area (Obi Obi Creek, Maleny, QLD). Several major enhancements have been developed to produce higher quality visualisations, including display of more types of data, support for larger models and improved user interaction. The graphics and animation capabilities have also been enhanced, notably the display of boreholes, depth logs and time-series water level surfaces. The GVS software remains under continual development and improvement

Polybrominated diphenyl ether (PBDE) concentrations decrease with age : analysis of pooled human blood serum in the Australian population

Introduction Polybrominated diphenyl ethers (PBDEs) are considered to be a cost effective and efficient way to reduce the possibility of product ignition and inhibit the spread of fire, thereby limiting harm caused by fires. PBDEs are incorporated into a wide variety of manufactured products and are now considered an ubiquitous contaminant found worldwide in biological and environmental samples1 . In comparison to “traditional” persistent organic pollutants (POPs), the exposure modes of PBDEs in humans are less well defined, although dietary sources, inhalation (air/particulate matter) and dust ingestion have been reported 2-4. Limited investigations of population specific factors such as age or gender and PBDE concentrations report: no conclusive correlation by age in adults; higher concentrations in children ; similar concentrations in maternal and cord blood; and no gender differences. After preliminary findings of higher PBDE concentrations in children than in adults in Australia11 we sought to investigate at what age the PBDE concentrations peaked in an effort to focus exposure studies. This investigation involved the collection of blood samples from young age groups and the development of a simple model to predict PBDE concentrations by age in Australia.

Thrown in the deep end : newcomers and public sector reform

Triggered by the continuing global financial crisis, most public administration systems internationally are reviewing their ability to meet public expectations in more challenging strategic environments, while satisfying the pressure from their political masters to drive down the costs of public administration. Consequently public sector organizations are under constant pressure to reform to meet not only the global economic challenges, but the need for more responsive government (Brown et al 2003). Doyle et al (2000) propose that organizational change is seldom well managed, but that the public sector faces greater difficulty in implementing corporate change than the private sector because of its unique environment, e.g. the need to deliver bureaucratically impartial outcomes. The scale of the changes required, and the constraints imposed by the context within which these changes need to occur, have intensified the need for capable public sector leadership and management. The types of capability required now extend beyond those typically required in public organizations through the efficiency drive of new public management. Acquiring these capabilities remains a key issue for public organizations. One challenge for public management, then, is leadership and management quality, including the need to recruit externally to refresh, re-energize and change the sector and its individual organizations as well as develop advanced skills among existing senior executives.

Strategic technology management : case study development in innovative building products

National and international competition demands that Australian organisations become more competent at making the strategic technological decisions that impact their future in the international business economy. A new subject unit, Management of Technology is now offered in the popular Master of Project Management and Master of Business Administration programs at the Queensland University of Technology. This cross-disciplinary subject provides students with a theoretical foundation and practical tools to improve the efficiency and competitiveness of technically-oriented organisations. Applied case studies—shown to be the most appropriate mode of learning for mature-age students—form an integral component of the teaching program. In the first offerings of this subject during 1995 and 1996, American case studies were used. QUT has now supported the development of Australian case study packages for technology management through its Teaching and Learning Grants Scheme. The first case developed—Inland Oil Refiners’ Microstill Project—was completed in early 1996. A newly developed case—Automated Door Opening System for Wheelchair Access—is currently being completed. This case (comprising case study documentation and video presentation) tracks a cross-disciplinary product development driven by legislative and community pressures. It also reinforces the importance of personal relationships in the technology and business development that has taken this young Brisbane-based company from its embryonic beginnings on the Queensland Cultural Centre in 1994 to a national and export-focussed organisation in 1997. This paper reviews the need to develop Australian case material in Management of Technology, discusses the case study documentation and supporting video developed, and application of the case study approach in this teaching initiative in QUT’s Master of Project Management and Master of Business Administration programs.

Pedagogy of feedback on student academic writing : research supervisor practices for the end of the research degree candidature

All academic writing is advanced with the benefit of feedback about the writing. In the case of the academic writing genres of the research proposal and the dissertation, feedback is usually provided by the research supervisor. Given that academic writing development is a process, and in the case of the research proposal and dissertation, writing which develops over time, it seems likely that the nature of feedback on drafts written early in the candidature may be different from feedback provided by the research supervisor later in a student’s candidature. ----- ----- When a research supervisor has been reading a student’s writing over a period of time, their own familiarity with the writing generates a risk to their ability to provide critical and objective feedback. Particularly by the end of a student’s candidature, the research supervisor’s familiarity with the work may cause them to miss elements of writing improvement. ----- ----- The author, as a research supervisor, has developed a feedback grid to facilitate feedback on the final drafts of a dissertation. This feedback grid is generated by the embedded promises in the early sections of the dissertation, which are then used to audit the content of the final sections of the dissertation to ascertain whether promises made have been fulfilled. This provides a strategy for the research supervisor to step back from the work and read the dissertation with the agenda of a dissertation examiner. ----- ----- The grid is one strategy within a broader pedagogy of providing feedback on writing samples.

Deep End Teacher Guide : Green

Dr Mills is also the invited author of the Deep End Series Teacher Guides by ERA publications. This 3-volume series for teachers is used in more than 200 schools in Australia, the USA, Canada, New Zealand, Sweden, Norway, and South America.

Deep End Teacher Guide : Orange

Dr Mills is the invited author of the Deep End Series Teacher Guides by ERA publications. This 3-volume series for teachers is used in more than 200 schools in Australia, the USA, Canada, New Zealand, Sweden, Norway, and South America.

Deep End Purple Teacher Guide

Dr Mills is also the invited author of the Deep End Series Teacher Guides by ERA publications. This 3-volume series for teachers is used in more than 200 schools in Australia, the USA, Canada, New Zealand, Sweden, Norway, and South America.