Effect of μPlasma Modification on the Wettability and the Ageing Behaviour of Glass Fibre Reinforced Polyamide 6 (GFPA6)

Glass fibre reinforced polyamide 6 (GFPA6) thermoplastic composites (TPCs) are promising materials with excellent properties, but due to their low surface free energy they are usually difficult to wet, and therefore, possesses poor adhesion properties. μPlasma modification offers potential solutions to this problem through functionalisation of the GFPA6 surface. In this study, the effect of μPlasma on the wetting behaviour of GFPA6 surfaces was investigated. Following single μPlasma treatment scans of GFPA6 samples, a substantial enhancement in wettability was observed. However, the effect of the μPlasma modification was subject to an ageing (hydrophobic recovery) phenomenon, although the enhancement was still partially maintained after 4 weeks. The ageing process was slower when the GFPA6 material was pre-dried and stored in low humidity conditions, thereby demonstrating the importance of the storage environment to the rate of ageing. Orientation of the fibres to the observed contact angle was found to be crucial for obtaining reproducible measurements with lower deviation. The influence of testing liquid, droplet volume and surface texture on the repeatability of the measured contact angle were also investigated.

Ageing rate of older adults affects the factors associated with, and the determinants of malnutrition in the community: a systematic review and narrative synthesis

Background Malnutrition negatively impacts on health, quality of life and disease outcomes in older adults. The reported factors associated with, and determinants of malnutrition, are inconsistent between studies. These factors may vary according to differences in rate of ageing. This review critically examines the evidence for the most frequently reported sociodemographic factors and determinants of malnutrition and identifies differences according to rates of ageing. Methods A systematic search of the PubMed Central and Embase databases was conducted in April 2019 to identify papers on ageing and poor nutritional status. Numerous factors were identified, including factors from demographic, food intake, lifestyle, social, physical functioning, psychological and disease-related domains. Where possible, community-dwelling populations assessed within the included studies (N = 68) were categorised according to their ageing rate: ‘successful’, ‘usual’ or ‘accelerated’. Results Low education level and unmarried status appear to be more frequently associated with malnutrition within the successful ageing category. Indicators of declining mobility and function are associated with malnutrition and increase in severity across the ageing categories. Falls and hospitalisation are associated with malnutrition irrespective of rate of ageing. Factors associated with malnutrition from the food intake, social and disease-related domains increase in severity in the accelerated ageing category. Having a cognitive impairment appears to be a determinant of malnutrition in successfully ageing populations whilst dementia is reported to be associated with malnutrition within usual and accelerated ageing populations. Conclusions This review summarises the factors associated with malnutrition and malnutrition risk reported in community-dwelling older adults focusing on differences identified according to rate of ageing. As the rate of ageing speeds up, an increasing number of factors are reported within the food intake, social and disease-related domains; these factors increase in severity in the accelerated ageing category. Knowledge of the specific factors and determinants associated with malnutrition according to older adults’ ageing rate could contribute to the identification and prevention of malnutrition. As most studies included in this review were cross-sectional, longitudinal studies and meta-analyses comprehensively assessing potential contributory factors are required to establish the true determinants of malnutrition.

Features and factors of demographic dynamics in the Kyrgyz Republic

The article analyzes the current demographic situation in the Kyrgyz Republic, as well as the main components of population dynamics: natural population growth, internal mobility and international migration. Basing on census data, current statistics and population surveys, the authors assess the impact of demographic processes in the republic on the age and sex structure and the rate of ageing of the Kyrgyz population, as well as on population settlement and its concentration in the centres of attraction of internal migrants, and the urbanization process. Analysis of demographic dynamics in the Kyrgyz Republic has shown a number of interrelated problems and challenges caused by the rapid growth of the population and changes in its age structure, requiring urgent social and economic policy measures. Key of the revealed problems are mass departure of the population in the working age, especially young people (labour migration), growth of population of retirement age, and uneven population settlement with concentration around the two largest urban agglomerations of the republic, the cities of Bishkek and Osh.

The long lives of primates and the ‘invariant rate of ageing’ hypothesis

Is it possible to slow the rate of ageing, or do biological constraints limit its plasticity? We test the ‘invariant rate of ageing’ hypothesis, which posits that the rate of ageing is relatively fixed within species, with a collection of 39 human and nonhuman primate datasets across seven genera. We first recapitulate, in nonhuman primates, the highly regular relationship between life expectancy and lifespan equality seen in humans. We next demonstrate that variation in the rate of ageing within genera is orders of magnitude smaller than variation in pre-adult and age-independent mortality. Finally, we demonstrate that changes in the rate of ageing, but not other mortality parameters, produce striking, species-atypical changes in mortality patterns. Our results support the invariant rate of ageing hypothesis, implying biological constraints on how much the human rate of ageing can be slowed.

Ageing affects subtelomeric DNA methylation in blood cells from a large European population enrolled in the MARK-AGE study

Ageing leaves characteristic traces in the DNA methylation make-up of the genome. However, the importance of DNA methylation in ageing remains unclear. The study of subtelomeric regions could give promising insights into this issue. Previously reported associations between susceptibility to age-related diseases and epigenetic instability at subtelomeres suggest that the DNA methylation profile of subtelomeres undergoes remodelling during ageing. In the present work, this hypothesis has been tested in the context of the European large-scale project MARK-AGE. In this cross-sectional study, we profiled the DNA methylation of chromosomes 5 and 21 subtelomeres, in more than 2000 age-stratified women and men recruited in eight European countries. The study included individuals from the general population as well as the offspring of nonagenarians and Down syndrome subjects, who served as putative models of delayed and accelerated ageing, respectively. Significant linear changes of subtelomeric DNA methylation with increasing age were detected in the general population, indicating that subtelomeric DNA methylation changes are typical signs of ageing. Data also show that, compared to the general population, the dynamics of age-related DNA methylation changes are attenuated in the offspring of centenarian, while they accelerate in Down syndrome individuals. This result suggests that subtelomeric DNA methylation changes reflect the rate of ageing progression. We next attempted to trace the age-related changes of subtelomeric methylation back to the influence of diverse variables associated with methylation variations in the population, including demographics, dietary/health habits and clinical parameters. Results indicate that the effects of age on subtelomeric DNA methylation are mostly independent of all other variables evaluated.

Sex Differences in the Dynamic Component of Postural Balance in Older Adults

Gait and balance disorders are common in older adults and represent a multifaceted problem resulting from a combination of natural involutional processes and various pathological conditions. However, to date, the dynamic component of postural balance in older adults remains poorly studied. In order to determine sex differences in the dynamic component of postural balance, 40 older men and 40 older women were tested (Sit-to-Stand, Walk Across, Tandem Walk, Step/Quick Turn, Step-Up-and- Over tests) using the computer-aided stabilometric complex Balance Master. The research found that in older women, the parameters of the dynamic component of postural balance are more intact than in men, probably due to a slower rate of ageing.

Larval diet affects adult reproduction but not survival regardless of injury and infection stress in Drosophila melanogaster

ABSTRACTEarly-life conditions have profound effects on many life-history traits. In particular, early-life diet affects both juvenile development, and adult survival and reproduction. Early-life diet also has consequences for the ability of adults to withstand stressors such as starvation, temperature and desiccation. However, it is less well known how early-life diet influences the ability of adults to respond to infection. Here we test whether varying the larval diet of female Drosophila melanogaster (through altering protein to carbohydrate ratio, P:C) influences the long-term response to injury and infection with the bacterial pathogen Pseudomonas entomophila. Given previous work manipulating adult dietary P:C, we predicted that adults from larvae raised on higher P:C diets would be more likely to survive infection and have increased reproduction, but shorter lifespans and an increased rate of ageing. For larval development, we predicted that low P:C would lead to a longer development time and lower viability. We found that early-life and lifetime egg production were highest at intermediate to high larval P:C diets, but there was no effect of larval P:C on adult survival. Larval diet had no effect on survival or reproduction post-infection. Larval development was quickest on intermediate P:C and egg-to-pupae and egg-to-adult viability were higher on higher P:C. Overall, despite larval P:C affecting several traits measured in this study, we saw no evidence that larval P:C altered the consequence of infection or injury for adult survival and early-life and lifetime reproduction. Taken together, these data suggest that larval diets appear to have a limited impact on adult response to infection.

A retrospective and prospective view of current and future population ageing in the European Union 28 countries

Population ageing in the EU28 is an important twenty-first century phenomenon, affecting virtually every aspect of life in these countries. The results of the latest EUROPOP2018 population forecast indicate that the rate of ageing is accelerating. The aim of this paper is to analyse the current level of population ageing in the EU28, identify spatial differences, and point to likely trends by the middle of this century. For these purposes, we have used a combination of conventional chronological indicators of population ageing and a set of new indicators based on prospective age that allows for a more comprehensive and realistic view of population ageing. We use multivariate statistical methods (factor and cluster analysis) to identify groups of countries with similar population ageing characteristics, using both a retrospective and prospective approach. We decompose changes in selected ageing indicators into the separate effects of changes in the population composition (children under 15, working-age population, elderly). We then identify the effect of major demographic factors (migration, mortality, cohort turnover) for the set of EU28 countries

Factors of fertility ageing rate

The current demographic model of most developed countries is characterized by ageing and declining fertility. Despite the fact that this topic has been studied quite thoroughly, the question remains: what national indicators does the rate of ageing fertility depend on in different groups of countries? An analysis of some developed countries between 1990 and 2017 enables concluding that the dynamics of intensity of the first births over the age of 35 in the group of developed countries is negatively influenced by the dynamics of employment and the share of services in GDP, while the maternal age at first birth in the group of former socialist countries depends on the dynamics of the education indicator.