A Review and Reassessment of Travertine Classification

This paper provides a review of the classification of travertines with emphasis on their morphology. Three criteria are used to describe them: geochemistry, microfabric and morphology. Geochemically, travertines may be divided into two groups, the meteogene travertines, where the carrier carbon dioxide originates in the soil and epigean atmosphere, and the thermal (thermogene) travertines where the carbon dioxide comes from thermally generated sources. Many travertine fabrics are influenced by bacteria and plants. These include 'stromatolitic' forms, many oncoids, shrubs, tufts, mats and moss travertines. Morphologically, travertines are conveniently divided into autochthonous (spring mounds and ridges, cascades, barrages, fluvial and lacustrine crusts, paludal deposits and cemented rudites) and the allochthonous or clastic travertines (valley-fills, back-barrage deposits, alluvial cones). Travertine deposits often include a wide range of fabrics and morphologies in one system. They are influenced locally by discharge, slope, vegetation, climate and human activity. Intergradations occur, both within travertine types but also with other freshwater deposits, e.g. calcrete and lake chalk. The influence of travertine deposition on the local hydrology and geomorphology is also discussed. The review emphasises the significance of scale and hydrology and aims to provide a unified scheme of travertine classification.Cette revue met l'accent sur la morphologie des travertins. Leur description repose sur trois critères : la géochimie, la microfabrique et la morphologie. Du point de vue de la géochimie, les travertins peuvent être divisés en deux groupes : les travertins d'eau météorique, où le dioxide de carbone provient du sol ou de la surface, et les travertins d'eau thermale, où le dioxide de carbone provient de sources thermales. La fabrique des travertins est souvent influencée par la présence des bactéries et des plantes, ce qui comprend des stromatolithes, de nombreux oncolithes et diverses formes caractéristiques. Du point de vue de la morphologie, les travertins sont autochtones (monticules, cascades, barrages, encroûtements fluviatiles ou lacustres, dépôts palustres et rudites cimentées) ou allochtones (dépôts de remblaiement de vallée, de remplissage amont de barrage, de cônes alluviaux). Les dépôts travertineux comprennent souvent un assortiment de fabriques et de morphologies comprises dans un seul ensemble selon le débit, la pente, la végétation, le climat et les activités humaines. On discute également de l'effet de la mise en place du travertin sur l'hydrologie locale et la géomorphologie. Cette revue fait ressortir l'importance de l'échelle et de l'hydrologie et tente de faire ressortir une vision intégrée de la classification des travertins.Dieser Aufsatz gibt einen ûberblick ùber die Klassifizierung der Travertine unter Hervorhebung ihrer Morphologie. Bei ihrer Beschreibung werden drei Kriterien benutzt: Geochemie, Mikrostruktur und Morphologie. Geochemisch kann man die Travertine in zwei Gruppen aufteilen: die Verwitterungs-Travertine, wo das Trâger-Kohlendioxyd aus dem Boden und der epigenetischen Atmosphâre stammt, und die thermischen Travertine, wo das Kohlendioxyd aus thermisch erzeugten Quellen kommt. Viele Travertin-Strukturen sind durch Bakterien und Pflanzen beeinfluBt. Dies umfaBt "stromatolithische" Formen, zahlreiche Onkoide, Straucher, Bûschel, Matten und Moos-Travertine. Morphologisch teilt man am besten die Travertine in autochthone (Bodenerhebungen und Rùcken Wasserfàlle, Dàmme, FIuR- und Seeverkrustungen, Sumpfablagerungen und verkittete Rudite) und in allochthone oder klastische Travertine (Tal-Auffùllungen, Ablagerungen hinter Dâmmen, alluviale Kegel). Die Travertin-Ablagerungen enthalten oft eine groBe Auswahl von Strukturen und Morphologien in einem einzigen System. Sie sind ôrtlich beeinfluBt durch Wasserfùhrung, Bôschung, Vegetation, Klima und menschliche Aktivitâten. Intergradation kommt vor, sowohl innerhalb der Travertin-Typen aber auch mit anderen Frischwasser-Ablagerungen, z.B. Kalkkrusten und See-Kreide. Auch wird der EinfluB der Travertin-Ablagerung auf die ôrtliche Hydrologie und Géomorphologie diskutiert. Der ûberblick hebt die Bedeutung von MaBstab und Hydrologie hervor und suent ein vereinheillichtes Schema der Travertin-Klassifikation zu geben

A note on freshwater research in China, with some observations on the algae from Doupe Pool, Guizhou Province

This article provides insights into a particular aspect of freshwater research in China and its wider implications for western researchers. The senior author has collaborated with Professor Zhang Zhaohui from Guizhou Normal University to investigate the travertines of China. Travertines are freshwater carbonate deposits accumulating in hard-water springs and rivers. In some areas they develop rapidly, forming picturesque ascades and magnificent travertine-dammed lakes. Some of China's most famous tourist sites are the result of travertine formation. The travertine-depositing environment is a unique fast-flowing ecosystem inhabited by specialist plants and animals. The authors examine the freshwater algae of the Doupe Pool travertine situated on the Beishuihei River in Guizhou Province and compare their distribution on travertines elsewhere in the world

A note on freshwater research in China, with some observations on the algae from Doupe Pool, Guizhou Province

This article provides insights into a particular aspect of freshwater research inChina and its wider implications for western researchers. China's researchactivities, although extensive, are the least known of all the world's majorcountries. This results from two factors. The written Chinese language with itsthousands of characters is known to few western researchers, and althoughmost Chinese research papers provide an English summary, the importantdetail is inaccessible to most researchers, as indeed are the journalsthemselves. The second important factor is that China was effectively isolatedfrom the west for a period of some thirty years, from the 1950s until the early1980s. However, there was collaboration with the Soviet Union and Russianbecame a second language for most Chinese academics during that period.Few academics knew any English, and even today it is the youngerresearchers who tend to have a better command of that language

Dyadic perspectives on loneliness and social isolation among people with dementia and spousal carers: findings from the IDEAL programme

YesThis study aims to investigate the impact of self and partner experiences of loneliness and social isolation on life satisfaction in people with dementia and their spousal carers. We used data from 1042 dementia caregiving dyads in the Improving the experience of Dementia and Enhancing Active Life (IDEAL) programme cohort. Loneliness was measured using the six-item De Jong Gierveld loneliness scale and social isolation using the six-item Lubben Social Network Scale. Data were analysed using the Actor-Partner Interdependence Model framework. Self-rated loneliness was associated with poorer life satisfaction for both people with dementia and carers. The initial partner effects observed between the loneliness of the carer and the life satisfaction of the person with dementia and between social isolation reported by the person with dementia and life satisfaction of the carer were reduced to nonsignificance once the quality of the relationship between them was considered. Experiencing greater loneliness and social isolation is linked with reduced life satisfaction for people with dementia and carers. However, having a positive view of the quality of the relationship between them reduced the impact of loneliness and social isolation on life satisfaction. Findings suggest the need to consider the experiences of both the person with dementia and the carer when investigating the impact of loneliness and social isolation. Individual interventions to mitigate loneliness or isolation may enhance life satisfaction for both partners and not simply the intervention recipient.‘Improving the experience of Dementia and Enhancing Active Life: living well with dementia. The IDEAL study’ was funded jointly by the Economic and Social Research Council (ESRC) and the National Institute for Health and Care Research (NIHR) through grant ES/L001853/2. ‘Improving the experience of Dementia and Enhancing Active Life: a longitudinal perspective on living well with dementia. The IDEAL-2 study’ is funded by Alzheimer’s Society, grant number 348, AS-PR2-16- 001

Effects of social restrictions on people with dementia and carers during the pre-vaccine phase of the COVID-19 pandemic: experiences of IDEAL cohort participants

Copyright © 2022 The Author(s). This qualitative study was designed to understand the impact of social distancing measures on people with dementia and carers living in the community during a period of ongoing restrictions before the COVID-19 vaccination roll-out in England and Wales. We conducted semi-structured interviews with 11 people with dementia and 10 carers (including 3 dyads) living in the community in England and Wales. Participants were recruited during November and December 2020. We used framework analysis to identify issues and elicit suggestions for potential solutions. We identified three interrelated themes. People with dementia experienced a fear of decline in capabilities or mood and attempted to mitigate this. Carers were aware of changes in the person with dementia and an increase in caring responsibilities and for some, there was a change in the relationship. Subsequently, reduced confidence in capabilities to navigate a new and hostile environment created a cyclical dilemma of returning to ‘normal’ where not returning to usual activities made things worse. People with dementia and carers had feelings of neglect and being alone in their struggle, alongside feeling socially excluded during the pandemic when comparing themselves to others in society, and there was little optimism associated with the upcoming vaccine programme. People found their own solutions to reduce the effects of isolation by keeping busy and socially active and practising skills deemed to help reduce the progression of dementia. This and some limited local public initiatives for the general public facilitated feelings of social inclusion. This study adds understanding to existing evidence about the longer-term experience of social isolation several months into the pandemic highlighting the importance of health and community groups and how services can find ways to support, include and interact with people with dementia and carers during and after social restrictions.‘Identifying and mitigating the individual and dyadic impact of COVID-19 and life under physical distancing on people with dementia and carers (INCLUDE)’ was funded by the Economic and Social Research Council (ESRC) through grant ES/V004964/1. Investigators: Clare, L., Victor, C., Matthews, F., Quinn, C., Hillman, A., Burns, A., Allan, L., Litherland, R., Martyr, A., Collins, R., & Pentecost, C. ESRC is part of UK Research and Innovation (UKRI); ‘Improving the experience of Dementia and Enhancing Active Life: living well with dementia. The IDEAL study’ was funded jointly by the Economic and Social Research Council (ESRC) and the National Institute for Health Research (NIHR) through grant ES/L001853/2. Investigators: L. Clare, I.R. Jones, C. Victor, J.V. Hindle, R.W. Jones, M. Knapp, M. Kopelman, R. Litherland, A. Martyr, F.E. Matthews, R.G. Morris, S.M. Nelis, J.A. Pickett, C. Quinn, J. Rusted, J. Thom. ESRC is part of UK Research and Innovation (UKRI). IDEAL data were deposited with the UK data archive in April 2020 and will be available to access from April 2023. Details of how the data can be accessed after that date can be found here: http://reshare.ukdataservice.ac.uk/854293/; ‘Improving the experience of Dementia and Enhancing Active Life: a longitudinal perspective on living well with dementia. The IDEAL-2 study’ is funded by Alzheimer’s Society, grant number 348, AS-PR2-16-001; Investigators: L. Clare, I.R. Jones, C. Victor, C. Ballard, A. Hillman, J.V. Hindle, J. Hughes, R.W. Jones, M. Knapp, R. Litherland, A. Martyr, F.E. Matthews, R.G. Morris, S.M. Nelis, C. Quinn, J. Rusted. L. Clare and L Allan acknowledge support from the NIHR Applied Research Collaboration South-West Peninsula. The views expressed are those of the author(s) and not necessarily those of the ESRC, UKRI, NIHR, the Department of Health and Social Care, the National Health Service, or Alzheimer’s Society. The support of ESRC, NIHR and Alzheimer’s Society is gratefully acknowledged

Comorbid health conditions and their impact on social isolation, loneliness, quality of life, and well-being in people with dementia: longitudinal findings from the IDEAL programme

\ua9 2024, The Author(s).Background: Most people with dementia have multiple health conditions. This study explores (1) number and type of health condition(s) in people with dementia overall and in relation to age, sex, dementia type, and cognition; (2) change in number of health conditions over two years; and (3) whether over time the number of health conditions at baseline is related to social isolation, loneliness, quality of life, and/or well-being. Methods: Longitudinal data from the IDEAL (Improving the experience of Dementia and Enhancing Active Life) cohort were used. Participants comprised people with dementia (n = 1490) living in the community (at baseline) in Great Britain. Health conditions using the Charlson Comorbidity Index, cognition, social isolation, loneliness, quality of life, and well-being were assessed over two years. Mixed effects modelling was used. Results: On average participants had 1.8 health conditions at baseline, excluding dementia; increasing to 2.5 conditions over two years. Those with vascular dementia or mixed (Alzheimer’s and vascular) dementia had more health conditions than those with Alzheimer’s disease. People aged ≥ 80 had more health conditions than those aged < 65 years. At baseline having more health conditions was associated with increased loneliness, poorer quality of life, and poorer well-being, but was either minimally or not associated with cognition, sex, and social isolation. Number of health conditions had either minimal or no influence on these variables over time. Conclusions: People with dementia in IDEAL generally had multiple health conditions and those with more health conditions were lonelier, had poorer quality of life, and poorer well-being

Correlates of felt age in caregivers of people with dementia: findings from the IDEAL study

Objective: Family relationships influence how people appraise their own aging and how their appraisals impact their health. We analyzed felt age (FA) among family caregivers of people with dementia. Methods and measures: We used a stratified sample of 1,020 spousal and 202 adult-child caregivers from the IDEAL study. We estimated cross-sectional associations and bidirectional influences between caregivers' FA and their health and wellbeing (depression, number of health conditions, stress, positive aspects of caregiving) over 2 years. Results: Among spousal caregivers, 25% had a younger FA and 36% had an older FA. Among adult-child caregivers, 21.8% had a younger FA and 36.1% had an older FA. In spousal and adult-child caregivers an older FA was cross-sectionally associated with higher depression, number of health conditions, and stress, and fewer positive aspects of caregiving. In spousal caregivers, hours of care per day moderated the association between FA and depression, and FA was associated with stress 1 year later. Conclusion: Caregiving may impact FA and its relationship with health. We urge continued research on the connections between caregiving and FA, and how interventions might support caregivers' positive views on their own aging, which will translate views on aging scholarship to meaningfully improve caregivers' lives

Comorbid health conditions and their impact on social isolation, loneliness, quality of life, and well-being in people with dementia: longitudinal findings from the IDEAL programme

BackgroundMost people with dementia have multiple health conditions. This study explores (1) number and type of health condition(s) in people with dementia overall and in relation to age, sex, dementia type, and cognition; (2) change in number of health conditions over two years; and (3) whether over time the number of health conditions at baseline is related to social isolation, loneliness, quality of life, and/or well-being.MethodsLongitudinal data from the IDEAL (Improving the experience of Dementia and Enhancing Active Life) cohort were used. Participants comprised people with dementia (n = 1490) living in the community (at baseline) in Great Britain. Health conditions using the Charlson Comorbidity Index, cognition, social isolation, loneliness, quality of life, and well-being were assessed over two years. Mixed effects modelling was used.ResultsOn average participants had 1.8 health conditions at baseline, excluding dementia; increasing to 2.5 conditions over two years. Those with vascular dementia or mixed (Alzheimer’s and vascular) dementia had more health conditions than those with Alzheimer’s disease. People aged ≥ 80 had more health conditions than those aged < 65 years. At baseline having more health conditions was associated with increased loneliness, poorer quality of life, and poorer well-being, but was either minimally or not associated with cognition, sex, and social isolation. Number of health conditions had either minimal or no influence on these variables over time.ConclusionsPeople with dementia in IDEAL generally had multiple health conditions and those with more health conditions were lonelier, had poorer quality of life, and poorer well-being

Impact of COVID-19 on 'Living Well' with Mild-to-Moderate Dementia in the Community: Findings from the IDEAL Cohort

Background: Negative impacts of the COVID-19 pandemic on people with dementia have been widely-documented, but most studies have relied on carer reports and few have compared responses to information collected before the pandemic. Objective: We aimed to explore the impact of the pandemic on community-dwelling individuals with mild-to-moderate dementia and compare responses with pre-pandemic data. Methods: During the second wave of the pandemic, we conducted structured telephone interviews with 173 people with dementia and 242 carers acting as informants, all of whom had previously participated in the IDEAL cohort. Where possible, we benchmarked responses against pre-pandemic data. Results: Significant perceived negative impacts were identified in cognitive and functional skills and ability to engage in self-care and manage everyday activities, along with increased levels of loneliness and discontinuity in sense of self and a decline in perceived capability to 'live well'. Compared to pre-pandemic data, there were lower levels of pain, depression, and anxiety, higher levels of optimism, and better satisfaction with family support. There was little impact on physical health, mood, social connections and relationships, or perceptions of neighborhood characteristics. Conclusion: Efforts to mitigate negative impacts of pandemic-related restrictions and restore quality of life could focus on reablement to address the effects on participation in everyday activities, creating opportunities for social contact to reduce loneliness, and personalized planning to reconnect people with their pre-COVID selves. Such efforts may build on the resilience demonstrated by people with dementia and carers in coping with the pandemic

Health conditions in spousal caregivers of people with dementia and their relationships with stress, caregiving experiences, and social networks: longitudinal findings from the IDEAL programme

\ua9 The Author(s) 2024.Objectives: Longitudinal evidence documenting health conditions in spousal caregivers of people with dementia and whether these influence caregivers’ outcomes is scarce. This study explores type and number of health conditions over two years in caregivers of people with dementia and subgroups based on age, sex, education, hours of care, informant-rated functional ability, neuropsychiatric symptoms, cognition of the person with dementia, and length of diagnosis in the person with dementia. It also explores whether over time the number of health conditions is associated with caregivers’ stress, positive experiences of caregiving, and social networks Methods: Longitudinal data from the IDEAL (Improving the experience of Dementia and Enhancing Active Life) cohort were used. Participants comprised spousal caregivers (n = 977) of people with dementia. Self-reported health conditions using the Charlson Comorbidity Index, stress, positive experiences of caregiving, and social network were assessed over two years. Mixed effect models were used Results: On average participants had 1.5 health conditions at baseline; increasing to 2.1 conditions over two years. More health conditions were reported by caregivers who were older, had no formal education, provided 10 + hours of care per day, and/or cared for a person with more neuropsychiatric symptoms at baseline. More baseline health conditions were associated with greater stress at baseline but not with stress over time. Over two years, when caregivers’ health conditions increased, their stress increased whereas their social network diminished Discussion: Findings highlight that most caregivers have their own health problems which require management to avoid increased stress and shrinking of social network