The cytogenetic architecture of the aphid genome

In recent years aphids, with their well-defined polyphenism, have become favoured as model organisms for the study of epigenetic processes. The availability of the pea aphid (Acyrthosiphon pisum) genome sequence has engendered much research aimed at elucidating the mechanisms by which the phenotypic plasticity of aphids is inherited and controlled. Yet so far this research effort has paid little attention to the cytogenetic processes that play a vital part in the organisation, expression and inheritance of the aphid genome. Aphids have holocentric chromosomes, which have very different properties from the chromosomes with localised centromeres that are found in most other organisms. Here we review the diverse forms of aphid chromosome behaviour that occur during sex determination and male and female meiosis, often in response to environmental changes and mediated by endocrine factors. Remarkable differences occur, even between related species, that could have significant effects on the inheritance of all or parts of the genome. In relation to this, we review the particular features of the distribution of heterochromatin, rDNA genes and other repetitive DNA in aphid chromosomes, and discuss the part that these may play in the epigenetic modification of chromatin structure and function

Challenges and opportunity in mobility among older adults – key determinant identification

Abstract Background Attention is focused on the health and physical fitness of older adults due to their increasing age. Maintaining physical abilities, including safe walking and movement, significantly contributes to the perception of health in old age. One of the early signs of declining fitness in older adults is limited mobility. Approximately one third of 70-year-olds and most 80-year-olds report restrictions on mobility in their apartments and immediate surroundings. Restriction or loss of mobility is a complex multifactorial process, which makes older adults prone to falls, injuries, and hospitalizations and worsens their quality of life while increasing overall mortality. Objective The objective of the study is to identify the factors that have had a significant impact on mobility in recent years and currently, and to identify gaps in our understanding of these factors. The study aims to highlight areas where further research is needed and where new and effective solutions are required. Methods The PRISMA methodology was used to conduct a scoping review in the Scopus and Web of Science databases. Papers published from 2007 to 2021 were searched in November 2021. Of these, 52 papers were selected from the initial 788 outputs for the final analysis. Results The final selected papers were analyzed, and the key determinants were found to be environmental, physical, cognitive, and psychosocial, which confirms the findings of previous studies. One new determinant is technological. New and effective solutions lie in understanding the interactions between different determinants of mobility, addressing environmental factors, and exploring opportunities in the context of emerging technologies, such as the integration of smart home technologies, design of accessible and age-friendly public spaces, development of policies and regulations, and exploration of innovative financing models to support the integration of assistive technologies into the lives of seniors. Conclusion For an effective and comprehensive solution to support senior mobility, the determinants cannot be solved separately. Physical, cognitive, psychosocial, and technological determinants can often be perceived as the cause/motivation for mobility. Further research on these determinants can help to arrive at solutions for environmental determinants, which, in turn, will help improve mobility. Future studies should investigate financial aspects, especially since many technological solutions are expensive and not commonly available, which limits their use