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Objective: The goal of this paper was to optimize robust PID control for propofol anesthesia in children aged 5–10 years to improve performance, particularly to decrease the time of induction of anesthesia while maintaining robustness. Methods: We analyzed results of a previous study conducted by our group to identify opportunities for system improvement. Allometric scaling was introduced to reduce the interpatient variability and a new robust PID controller was designed using an optimization-based method. We evaluated this optimized design in a clinical study involving 16 new cases. Results: The optimized controller design achieved the performance predicted in simulation studies in the design stage. Time of induction of anesthesia was median [Q1, Q3] 3.7 [2.3, 4.1] min and the achieved global score was 13.4 [9.9, 16.8]. Conclusion: Allometric scaling reduces the interpatient variability in this age group and allows for improved closed-loop performance. The uncertainty described by the model set, the predicted closed-loop responses, and the predicted robustness margins are realistic. The system meets the design objectives of improved speed of induction of anesthesia while maintaining robustness and improving clinically relevant system behavior. Significance: Control system optimization and ongoing system improvements are essential to the development of a clinically relevant commercial device. This paper demonstrates the validity of our approach, including system modeling, controller optimization, and pre-clinical testing in simulation. [ABSTRACT FROM AUTHOR]

Ageing well has been associated with the responsibility to age actively, successfully, or healthily in public and research discourses. This connection of individual responsibility with ageing has been criticised in Social Gerontology for neglecting the access to social, economic, and health resources. This paper investigates (individual) responsibility, informal support, and public initiatives in discourses on older immigrants in Germany. The research framework employs a sociology of knowledge approach to discourse, which guided the discourse analysis of German policy reports, guidelines and handbooks on ageing and migration from 2000 to 2019 (43 documents in total). The results reveal that besides public initiatives concerning long-term care, health promotion, and social services, informal solutions through social networks are frequently emphasised in the data. The focus, thereby, is on long-term care, which is presented as a responsibility of the extended family. Thus, resources are situated in the family, social networks, and ethnic group, which should be opened and connected with public services; however, the focus is shifting from older immigrants towards local municipalities. This study provides a discourse perspective on the construction of resources and challenges for older immigrants concerning health, care, and social services and offers an assessment of the cultural and integrating/excluding qualities in active ageing discourses. [ABSTRACT FROM AUTHOR]

Background: Consideration of older adults’ quality of life (QoL) is becoming increasingly important in the evaluation, quality improvement and allocation of health and social care services. While numerous definitions and theories of QoL have been proposed, an overall synthesis of the perspective of older adults themselves is lacking. Methods: Qualitative studies were identified in PubMed, Ebsco/Psycinfo and Ebsco/CINAHL, through a search on 28 November 2018. Articles needed to meet all of the following criteria: (i) focus on perceptions of QoL, (ii) older adults living at home as main participants, (iii) use of qualitative methodology, (iv) conducted in a Western country and (v) published in English (vi) not focused on specific patient groups. A thematic synthesis was conducted of the selected studies, using the complete ‘findings/results’ sections from the papers. Results: We included 48 qualitative studies representing the views of more than 3,400 older adults living at home in 11 Western countries. The QoL aspects identified in the synthesis were categorized into nine QoL domains: autonomy, role and activity, health perception, relationships, attitude and adaptation, emotional comfort, spirituality, home and neighbourhood, and financial security. The results showed that although different domains can be distinguished, these are also strongly connected. Conclusion: QoL can be expressed in a number of domains and related subthemes that are important for older adults living at home. The findings further support that the concept of QoL should be seen as a dynamic web of intertwined domains. [ABSTRACT FROM AUTHOR]

Telomere length (TL) has been associated with a range of aging outcomes as well as mortality. Recent research has shown both high heritability (~70%) of TL as well as moderate spousal similarity (r~0.3) using European datasets. This paper explores the level of spousal concordance in telomere length in the Health and Retirement Study, a national sample of adults in the US. The results show that the spousal correlations are lower (r~0.11). Regression-based associations in TL in the US are low (beta~0.08) and also vary by the number of times respondents have been married, where spouses married a single time have higher associations in TL (beta~.12) than spouses married more once (beta~0.03). I also find variation in spousal TL association levels based on husband’s education level. These findings suggest the possibility of both assortative mating patterns related to telomere length as well as likelihood of shared environmental factors that cause TL similarity in people who are socially connected. [ABSTRACT FROM AUTHOR]

Ageing concepts are very important in lifetime modeling and analysis. Monotonic failure rates are the simplest and most popular manifestations of aging properties of items in applications (IFR and DFR, accordingly). However, they are usually discussed for homogeneous populations, whereas heterogeneity can change dramatically the shape of the corresponding failure rate. In this paper, we suggest a new measure of ageing for items from heterogeneous populations based on the described process of information-based minimal repairs. We also show and illustrate, by several examples, that the conventional measure of aging based on the shape of the (population) failure rate is unrealistic in this case and can lead to wrong decisions, e.g., in burn-in procedures and optimal maintenance. [ABSTRACT FROM PUBLISHER]

In many social complex systems, in which agents are linked by non-linear interactions, the history of events strongly influences the whole network dynamics. However, a class of “commonly accepted beliefs” seems rarely studied. In this paper, we examine how the growth process of a (social) network is influenced by past circumstances. In order to tackle this cause, we simply modify the well known preferential attachment mechanism by imposing a time dependent kernel function in the network evolution equation. This approach leads to a fractional order Barabási-Albert (BA) differential equation, generalizing the BA model. Our results show that, with passing time, an aging process is observed for the network dynamics. The aging process leads to a decay for the node degree values, thereby creating an opposing process to the preferential attachment mechanism. On one hand, based on the preferential attachment mechanism, nodes with a high degree are more likely to absorb links; but, on the other hand, a node’s age has a reduced chance for new connections. This competitive scenario allows an increased chance for younger members to become a hub. Simulations of such a network growth with aging constraint confirm the results found from solving the fractional BA equation. We also report, as an exemplary application, an investigation of the collaboration network between Hollywood movie actors. It is undubiously shown that a decay in the dynamics of their collaboration rate is found, even including a sex difference. Such findings suggest a widely universal application of the so generalized BA model. [ABSTRACT FROM AUTHOR]

An increase in the exposure and predisposition of civilian populations to disasters has been recorded in the last decades. In major disasters, as demonstrated recently in Nepal (2015) and previously in Haiti (2010), external aid is vital, yet in the first hours after a disaster, communities must usually cope alone with the challenge of providing emergent lifesaving care. Communities therefore need to be prepared to handle emergency situations. Mapping the needs of the populations within their purview is a trying task for decision makers and community leaders. In this context, the elderly are traditionally treated as a susceptible population with special needs. The current study aimed to explore variations in the level of community resilience along the lifespan. The study was conducted in nine small to mid-size towns in Israel between August and November 2011 (N = 885). The Conjoint Community Resiliency Assessment Measure (CCRAM), a validated instrument for community resilience assessment, was used to examine the association between age and community resilience score. Statistical analysis included spline and logistic regression models that explored community resiliency over the lifespan in a way that allowed flexible modeling of the curve without prior constraints. This innovative statistical approach facilitated identification of the ages at which trend changes occurred. The study found a significant rise in community resiliency scores in the age groups of 61–75 years as compared with younger age bands, suggesting that older people in good health may contribute positively to building community resiliency for crisis. Rather than focusing on the growing medical needs and years of dependency associated with increased life expectancy and the resulting climb in the proportion of elders in the population, this paper proposes that active "young at heart" older people can be a valuable resource for their community. [ABSTRACT FROM AUTHOR]