Aging and everyday technology

This paper presents a literature review and indicative findings that are part of ongoing research into aging and technology. The review finds that research on older technology users has contributed valuable information on the impact of age-related changes on technology use, as well as older adults’ acceptance and adoption of contemporary technologies. However, the majority of the research has been conducted from the perspective of age-related differences in use and performance, or it is medically-focused, examining the potential of technology to improve an individual’s quality of life (QoL), for example. Research on older people and technology does not adequately address the integration of technology into the everyday lives of older people. This paper identifies that there is substantial opportunity to examine older users’ everyday information and communication technology (ICT) use, and to inform technology design beyond measures of performance, usability and adoption.

UVB irradiation alters the activities and kinetic properties of the enzymes of energy metabolism in rat lens during aging

Ultraviolet (UV) radiation is one of the major risk factors of cataract (loss of eye-lens transparency). The influence of UVB radiation (300 nm, 100 mu W cm(-2)) on the activity and apparent kinetic constants (K-m and V-max) of rat lens hexokinase (HK;EC2.7.1.1), phosphofructokinase (PFK;EC2.7.1.11), isocitrate dehydrogenase (ICDH;EC1.1.1.41) and malate dehydrogenase (MDH;EC1.1.1.37) of energy metabolism has been investigated by irradiating the lens homogenate of three-and 12-month-old rats. In the three-month-old group specific activities of HK and PFK are reduced by 56 and 43 %, respectively, and there is no change in ICDH and MDH activities after a 24 h exposure. On the other hand, in the 12-month-old group the decreases are 72, 71, 24 and 16 % for HK, PFK. ICDH and MDH, respectively. UVB irradiation increases the apparent K-m of HK and PFK (in both age groups), whereas the K-m of ICDH and MDH is not altered. While the decrease in V-max of these enzymes due to UVB exposure is only marginal in three-month-old rats, it is more pronounced (significant) in 12-month-old rats. A similar decrease in enzyme activities of HK and PFK is also observe upon UVB exposure of the intact rat lens. The photoinduced changes in energy metabolism may in turn have a bearing on lens transparency, particularly at an older age.

Accelerated Multistress Aging of Outdoor Polymeric Insulators

Multistress aging of outdoor composite polymeric insulators continues to be a topic of interest for power transmission research community. Aging due to dry conditions alone at elevated temperatures and electric stress in the presence of UV radiation environment probably has not been explored. This paper deals with long-term accelerated multistress aging under the above conditions on full-scale 11 kV distribution class composite silicone rubber insulators. To evaluate the long-term synergistic effect of electric stress, temperature and UV radiation on insulators, they were subjected to accelerated aging in a specially designed multistress-aging chamber for 12000 hours. Chemical, physical and electrical changes due to degradation have been assessed using various techniques. It has been found that the content of low molecular weight molecules and hydrophobicity reduced significantly. Also, due to oxidation and aging there is appreciable increase in surface roughness and weight percentage of oxygen. Study is under progress and only intermediate results are presented in this paper.

Aging-in-place: Perspectives from the construction industry

Older adults report a desire to remain within the preferred environment for as long as possible. This desire is referred to as aging-in-place. Aging-in-place integrates housing and care options. Factors affecting the ability to remain within the preferred environment include current home designs, access to housing choices, social support networks, and community services, to name a few. Research supports physical and psychosocial benefits of aging-in-place for the individual. Home modifications have the potential to influence the quality of life in a number of positive directions that range from personal mobility to community engagement. Modifications range from minor to significant. Financial resources, contractor interest and expertise, consumer awareness and consumer opportunity affect the degree of change. Increasingly, construction professionals express an interest in learning more about aging-in place. Queries ranged from obtaining a greater understanding of the meaning of the concept, impact of demographic change on housing stock, and increased awareness of universal design features. This paper presents findings from a survey administered to current members of the Canadian Home Builders’ Association – Calgary Regional Office. Within this presentation, we report findings on members understanding of demographic change and the effect of this change on the current and future housing stock. We discuss perceived barriers and benefits of the development of business models to support aging-in-place. Finally, we conclude with discussion of educational support to enhance the understanding of aging-in-place.

Seed persistence in the field may be predicted by laboratory-controlled aging

Weed management is complicated by the presence of soil seed banks. The complexity of soil-seed interactions means that seed persistence in the field is often difficult to measure, let alone predict. Field trials, although accurate in their context, are time-consuming and expensive to conduct for individual species. Some ex situ techniques for estimating seed life expectancy have been proposed, but these fail to simulate the environmental complexity of the field. Also, it has been questioned whether techniques such as the controlled aging test (CAT) are useful indicators of field persistence. This study aimed to test the validity of the standard CAT (seed aging at 45 C and 60% relative humidity) in use at the Royal Botanic Gardens, Kew, U.K., for predicting field seed-persistence. Comparison of seed persistence and CAT data for 27 northwest European species suggested a significant positive correlation of 0.31. Subsequently, 13 species of emerging and common weeds of Queensland were assessed for their seed longevity using the CAT. The seed longevity data of these species in the CAT were linked with field seed-persistence data according to three broad seed-persistence categories: <1 yr, 1 to 3 yr, and >3 yr. We discuss the scope for using the CAT as a tool for rapid assignment of species to these categories. There is a need for further studies that compare predictions of seed persistence based on the CAT with seed persistence in the field for a larger range of species and environments.

Cellular Mechanisms of Sleep Homeostasis : Studies on Brain Energy Metabolism and Aging

Sleep is governed by a homeostatic process in which the duration and quality of previous wake regulate the subsequent sleep. Active wakefulness is characterized with high frequency cortical oscillations and depends on stimulating influence of the arousal systems, such as the cholinergic basal forebrain (BF), while cessation of the activity in the arousal systems is required for slow wave sleep (SWS) to occur. The site-specific accumulation of adenosine (a by-product of ATP breakdown) in the BF during prolonged waking /sleep deprivation (SD) is known to induce sleep, thus coupling energy demand to sleep promotion. The adenosine release in the BF is accompanied with increases in extracellular lactate and nitric oxide (NO) levels. This thesis was aimed at further understanding the cellular processes by which the BF is involved in sleep-wake regulation and how these processes are affected by aging. The BF function was studied simultaneously at three levels of organization: 1) locally at a cellular level by measuring energy metabolites 2) globally at a cortical level (the out-put area of the BF) by measuring EEG oscillations and 3) at a behavioral level by studying changes in vigilance states. Study I showed that wake-promoting BF activation, particularly with glutamate receptor agonist N-methyl-D-aspatate (NMDA), increased extracellular adenosine and lactate levels and led to a homeostatic increase in the subsequent sleep. Blocking NMDA activation during SD reduced the high frequency (HF) EEG theta (7-9 Hz) power and attenuated the subsequent sleep. In aging, activation of the BF during SD or experimentally with NMDA (studies III, IV), did not induce lactate or adenosine release and the increases in the HF EEG theta power during SD and SWS during the subsequent sleep were attenuated as compared to the young. These findings implicate that increased or continuous BF activity is important for active wake maintenance during SD as well as for the generation of homeostatic sleep pressure, and that in aging these mechanisms are impaired. Study II found that induction of the inducible NO synthase (iNOS) during SD is accompanied with activation of the AMP-activated protein kinase (AMPK) in the BF. Because decreased cellular energy charge is the most common cause for AMPK activation, this finding implicates that the BF is selectively sensitive to the metabolic demands of SD as increases were not found in the cortex. In aging (study III), iNOS expression and extracellular levels of NO and adenosine were not significantly increased during SD in the BF. Furthermore, infusion of NO donor into the BF did not lead to sleep promotion as it did in the young. These findings indicated that the NO (and adenosine) mediated sleep induction is impaired in aging and that it could at least partly be due to the reduced sensitivity of the BF to sleep-inducing factors. Taken together, these findings show that reduced sleep promotion by the BF contributes to the attenuated homeostatic sleep response in aging.

Raw data for project "Development of a DNA based aging technique for use in fisheries assessments" Fisheries and Development Corporation project 2007/033

The primary aim of this study was to determine the relationship between telomere length and age in a range of marine invertebrates including abalone (Haliotis spp) oysters (Saccostrea glomerata), spiny lobsters (Sagmariasus verreauxi formerly Jasus verreauxi and Jasus edwardsii) and school prawns (Metapenaeus macleayi). Additionally, this relationship was studied in a vertebrate organism using the freshwater fish Silver perch (Bidyanus bidyanus). Telomere length differences between tissues were also examined in some species such as Saccostrea glomerata, Sagmariasus verreauxi and Bidyanus bidyanus. In some cases cultured specimens of known age were used and this is quoted in the spreadsheets. For other wild-caught specimens where age was not known, size was used as a proxy for age. This may be a broad size class, or be determined by shell size or carapace length depending on the organism. Each spreadsheet contains raw data of telomere length estimates from Terminal Restriction Fragment Assays (TRF) for various individuals of each species including appropriate details such as age or size and tissue. Telomere length estimates are given in base pairs (bp). In most cases replicate experiments were conducted on groups of samples three times but on a small number of occasions only two replicate experiments were conducted. Further description of the samples can be found in final report of FRDC 2007/033. The arithmetic average for each individual (sample ID) across the two or three replicate experiments is also given. Bidyanus bidyanus (SilverPerch) Two sheets are contained within. a) Comparison of telomere length between different tissues (heart, liver and muscle) within the three year old age class - two replicate experiments were conducted. b) Comparison of telomere length between fish of different but known ages (0.25, 1, 2, and 3 years old) in each of three tissues, heart, liver and muscle – three replicate experiments were conducted per tissue. Haliotis spp (Abalone species) Three species were tested. H. asinina Telomere length was compared in two age classes-11 month and 18 month old abalone using muscle tissue from the foot. Within gel-variation was also estimated using a single sample run three times on one gel (replicate experiment). H. laevigata x H. rubra hybrids Telomere length was compared in three known age classes – two, three and four years old using muscle tissue from the foot. H. rubra Telomere length was compared in a range of different sized abalone using muscle tissue from the foot. Shell size is also given for each abalone Saccostrea glomerata Three sheets are contained within the file. a) Samples came from Moreton Bay Queensland in 2007. Telomere length was compared in two tissues (gill and mantle) of oysters in three age groups (1, 3 and 4 years) b) Samples came from Moreton Bay Queensland in 2009. Telomere length was compared in three age classes using DNA from gill tissue only c) Samples came from Wallis Lake, New South Wales. Telomere length was estimated from whole body minus the shell from 1 year old oysters, gill tissue of 3 age classes (1.5 years, 3 and 4 years), mantle tissue of two age classes (3 and 4 years). Sagmariasus verreauxi (formerly Jasus verreauxi) Telomere length was estimated from abdomen tissue of puerulus, gill and muscle tissue of 3 year old, large and very large size classes of lobsters. Jasus edwardsii Telomere length was measured in two size classes of lobsters- adults of varying sizes using muscle tissue and puerulus using tissues from the abdomen minus the exoskeleton. Metapenaeus macleayi Telomere length was measured in three size classes of school prawns adults. Muscle tissue was used, minus the exoskeleton.

Chemical changes during the aging and decomposition of composite solid propellants

During the thermal decomposition of orthorhombic ammonium perchlorate (AP) at 230°C, where the decomposition is only up to 30 wt %, there is an accumulation in the solid of acids, the concentration of which increases up to 15% decomposition, after which it decreases till it reaches the original value. Similar observations have been made in the polystyrene (PS)/AP propellant systems. Aging studies of PS/AP propellants have been carried out earlier [1], where it has been shown that for the aged propellants the thermal decomposition (TD) rate at 230°C and 260°C and ambient pressure burning rate (Image ) both increase and this increase is due to the formation of reactive intermediate “polystyrene peroxide (PSP).” In the present studies it has been observed that during the aging of the propellant at 150°C, the acid is formed and gets accumulated in the propellant, which may also be responsible for the increase in TD rate and perhaps may be more effective than PSP.

Development of a DNA based aging technique for use in fisheries assessments. Final report, Australian Fisheries Research and Development Corporation Project 2007/033.

The productivity of a fisheries resource can be quantified from estimates of recruitment, individual growth and natural and fisheries-related mortality, assuming the spatial extent of the resource has been quantified and there is minimal immigration or emigration. The sustainability of a fisheries resource is facilitated by management controls such as minimum and maximum size limits and total allowable catch. Minimum size limits are often set to allow individuals the opportunity to reproduce at least once before the chance of capture. Total allowable catches are a proportion of the population biomass, which is estimated based on known reproduction, recruitment, mortality and growth rates. In some fisheries, however, management actions are put in place without quantification of the resource through the stock assessment process. This occurs because species-specific information, for example individual growth, may not be available. In these circumstances, management actions need to be precautionary to protect against future resource collapse, but this often means that the resource is lightly exploited. Consequently, the productivity of the resource is not fully realised. Australia’s most valuable fisheries are invertebrate fisheries (Australian Department of Agriculture Fisheries and Forestry, 2008). For example, Australian fisheries (i.e. excluding aquaculture) production of crustaceans (largely prawns, rock lobster and crab) was 41,000 tonnes in 2006/7, worth $778 million. Production from mollusc (largely abalone, scallops, oysters and squid) fisheries was 39,000 tonnes, worth $502 million. Together, in 2006/7 crustacean and mollusc fisheries represented 58% of the total value of Australian wild fisheries production. Sustainable management of Australia’s invertebrate fisheries is frustrated by the lack of data on species-specific growth rates. This project investigated a new method to estimate age, and hence individual growth rates, in invertebrate fisheries species. The principle behind the new aging method was that telomeres (i.e. DNA end-caps of chromosomes) get shorter as an individual gets older. We studied commercial crustacean and molluscan species. A vertebrate fish species (silver perch, Bidyanus bidyanus) was used as a control to standardise our work against the literature. We found a clear relationship between telomere length and shell size for temperate abalone (Haliotis rubra). Further research is recommended before the method can be implemented to assist management of wildharvested abalone populations. Age needs to be substituted for shell size in the relationship and it needs to be studied for abalone from several regions. This project showed that telomere length declined with increasing age in Sydney rock oysters (Saccostrea glomerata) and was affected by regional variation. A relationship was not apparent between telomere length and age (or size as a surrogate for age) for crustacean species (school prawns, Metapenaeus macleayi; eastern rock lobster, Sagmariasus verreauxi; southern rock lobster, Jasus edwardsii; and spanner crabs, Ranina ranina). For school prawns, there was no difference between telomere length in males and females. Further research is recommended, however, as telomeric DNA from crustaceans was difficult to analyse using the terminal restriction fragment (TRF) assay. Telomere lengths of spanner crabs and lobsters were at the upper limit of resolution of the assay used and results were affected by degradation and possible contamination of telomeric DNA. It is possible that telomere length is an indicator of remaining lifespan in molluscan and crustacean individuals, as suggested for some vertebrate species (e.g. Monaghan, 2010). Among abalone of similar shell size and among lobster pueruli, there was evidence of individuals having significantly longer or shorter telomeres than the group average. At a population level, this may be a surrogate for estimates of future natural mortality, which may have usefulness in the management of those populations. The method used to assay telomere length (terminal restriction fragment assay) performed adequately for most species, but it was too expensive and time-consuming to be considered a useful tool for gathering information for fisheries management. Research on alternative methods is strongly recommended.

The importance of a precise definition, comprehensive model, and critical discussion of successful aging at work

It is crucial to advance understanding of the concept of successful aging at work to guide rigorous future research and effective practice. Drawing on the gerontology and life-span developmental literatures, I recently proposed a definition and theoretical framework of successful aging at work that revolve around employees increasingly deviating from average developmental trajectories across the working life span. Based on sustainability, person–job fit, and proactivity theories, Kooij suggested an alternative perspective that emphasizes the active role of employees for successful aging at work. In this article, I compare the 2 approaches and attempt a partial integration. I highlight the importance of a precise definition, comprehensive model, and critical discussion of successful aging at work. Furthermore, I suggest that person–environment fit variables other than person–job fit (e.g., person–organization fit) and adapting to person–environment misfit may also contribute to successful aging at work. Finally, I argue that proactive behaviors must have age-differential effects on work outcomes to be considered personal resources for successful aging at work.

Work, aging, and retirement in Australia: Introduction to the special issue

Australia has an aging population and workforce, and policy makers and organizations increasingly encourage older workers to remain on the job longer and even beyond traditional retirement age. After a brief review of important demographic and political developments, we introduce the 8 articles included in this special issue on work, aging, and retirement in Australia. The articles include an overview of the Australian retirement income system, 6 articles reporting quantitative analyses of cross-sectional and longitudinal data provided by large samples of Australian workers and retirees, and a qualitative study which analyzes interviews with human resource managers. Overall, the articles demonstrate that research on work, aging, and retirement in Australia is flourishing, sophisticated, and diverse both in terms of content and methodologies. We close with a brief review of topics and research questions related to work, aging, and retirement that remain to be addressed in the Australian context in future research.

Successful aging at work

The expression successful aging at work and related terms such as active, healthy, and productive aging at work are frequently used by organizational researchers and practitioners. However, there are no concrete definitions or theoretical frameworks that explain their meaning, assumptions, and underlying processes. In this paper, I first review conceptualizations of successful aging in the fields of gerontology and life span psychology. Second, I propose a working definition of successful aging at work based on four key elements: criteria, explanatory mechanisms, facilitating and constraining factors, and temporal patterns. I distinguish successful aging at work from usual and unsuccessful aging and from other age-related developments in the work context. Third, I introduce a theoretical framework organized around 5 principles on intraindividual age-related change over time, person and contextual mediators and moderators, and work outcomes. Fourth, I review theoretical and empirical research on age in the workplace published in the past decade through the lens of the proposed theoretical framework. Finally, I conclude this paper by outlining suggestions for future research on successful aging at work, including methodological considerations.

Electrophoretic mobility of cell nuclei (EMN index) as a biomarker of the biological aging process: Considering the association between EMN index and age

The present study examined whether a specific property of cell microstructures may be useful as a biomarker of aging. Specifically, the association between age and changes of cellular structures reflected in electrophoretic mobility of cell nuclei index (EMN index) values across the adult lifespan was examined. This report considers findings from cross sections of females (n = 1273) aged 18–98 years, and males (n = 506) aged 19–93 years. A Biotest apparatus was used to perform intracellular microelectrophoresis on buccal epithelial cells collected from each individual. EMN index was calculated on the basis of the number of epithelial cells with mobile nuclei in reference to the cells with immobile nuclei per 100 cells. Regression analyses indicated a significant negative association between EMN index value and age for men (r = −0.71, p < 0.001) and women (r = −0.60, p < 0.001); demonstrating a key requirement that must be met by a biomarker of aging. The strength of association observed between EMN index and age for both men and women was encouraging and supports the potential use of EMN index for determining a biological age of an individual (or a group). In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. In this study, a new attempt of complex explanation of cellular mechanisms contributing to age related changes of the EMN index was made. EMN index has demonstrated potential to meet criteria proposed for biomarkers of aging and further investigations are necessary.

Why and when do learning goal orientation and attitude decrease with aging? The role of perceived remaining time and work centrality

We conducted two studies to improve our understanding of why and when older workers are focused on learning. Based on socioemotional selectivity theory, which proposes that goal focus changes with age and the perception of time, we hypothesized and found that older workers perceive their remaining time at work as more limited than younger workers which, in turn, is associated with lower learning goal orientation and a less positive attitude toward learning and development. Furthermore, we hypothesized and found that high work centrality buffers the negative association between age and perceived remaining time, and thus the indirect negative effects of age on learning goal orientation and attitude toward learning and development (through perceived remaining time). These findings suggest that scholars and practitioners should take workers’ perceived remaining time and work centrality into account when examining or stimulating learning activities among aging workers.

Aging response and its effect on the functional properties of Cu–Al–Ni shape memory alloys

The β-phase aging response of Cu–Al–Ni single crystal shape memory alloys (SMAs) within the temperature range of 473–573 K has been investigated. Alloys in austenitic (Cu–14.1Al–4Ni wt.%, alloy A) and martensitic (Cu–13.4Al–4Ni wt.%, alloy M) conditions at room temperature were considered. Aged samples show presence of β1′ and γ1′ martensites in both the alloys and formation of γ2 precipitates in the alloy A. The differential scanning calorimetry (DSC) thermograms of the aged samples show increase in transformation temperatures as well as transformation hysteresis with aging. Dynamic mechanical analysis (DMA) was conducted on both the alloys to ascertain the role of precipitates and martensitic transition on tan δ, which characterizes the damping behaviour of the material. With aging, a steady decrease in tan δ value was observed in both the alloys, which was attributed to the decrease in the number of interfaces per unit area with increasing aging temperature. Moreover, in alloy A, as the volume fraction of precipitate increases with aging, the movement of martensitic interfaces is restricted causing a decreased tan δ.