Igneous rock area and age in continental crust

Abstract Rock quantity and age are fundamental features of Earth's crust that pertain to many problems in geoscience. Here we combine new estimates of igneous rock area in continental crust from the Macrostrat database (https://macrostrat.org/) with a compilation of detrital zircon ages in order to investigate rock cycling and crustal growth. We find that there is little or no decrease in igneous rock area with increasing rock age. Instead, igneous rock area in North America exhibits four distinct Precambrian peaks, remains low through the Neoproterozoic, and then increases only modestly toward the recent. Peaks in Precambrian detrital zircon age frequency distributions align broadly with peaks in igneous rock area, regardless of grain depositional age. However, detrital zircon ages do underrepresent a Neoarchean peak in igneous rock area; young grains and ca. 1.1 Ga grains are also overrepresented relative to igneous area. Together, these results suggest that detrital zircon age distributions contain signatures of continental denudation and sedimentary cycling that are decoupled from the cycling of igneous source rocks. Models of continental crustal evolution that incorporate significant early increase in volume and increased sedimentation in the Phanerozoic are well supported by these data.</jats:p

In-n-out: The Gas Cycle From Dwarfs To Spiral Galaxies

We examine the scalings of galactic outflows with halo mass across a suite of 20 high-resolution cosmological zoom galaxy simulations covering halo masses in the range 10^9.5-10^12\M. These simulations self-consistently generate outflows from the available supernova energy in a manner that successfully reproduces key galaxy observables, including the stellar mass–halo mass, Tully–Fisher, and mass–metallicity relations. We quantify the importance of ejective feedback to setting the stellar mass relative to the efficiency of gas accretion and star formation. Ejective feedback is increasingly important as galaxy mass decreases; we find an effective mass loading factor that scales as v-circ-2.2, with an amplitude and shape that are invariant with redshift. These scalings are consistent with analytic models for energy-driven wind, based solely on the halo potential. Recycling is common: about half of the outflow mass across all galaxy masses is later reaccreted. The recycling timescale is typically ~1 Gyr, virtually independent of halo mass. Recycled material is reaccreted farther out in the disk and with typically ~2–3 times more angular momentum. These results elucidate and quantify how the baryon cycle plausibly regulates star formation and alters the angular momentum distribution of disk material across the halo mass range where most cosmic star formation occurs

Living well with dementia: An exploratory matched analysis of minority ethnic and white people with dementia and carers participating in the IDEAL programme

\ua9 2024 The Authors. International Journal of Geriatric Psychiatry published by John Wiley &amp; Sons Ltd.Objectives: The increasing heterogeneity of the population of older people is reflected in an increasing number of people with dementia and carers drawn from minority ethnic groups. Data from the IDEAL study are used to compare indices of ‘living well’ among people with dementia and carers from ethnic minority groups with matched white peers. Methods: We used an exploratory cross-sectional case-control design to compare ‘living well’ for people with dementia and carers from minority ethnic and white groups. Measures for both groups were quality of life, life satisfaction, wellbeing, loneliness, and social isolation and, for carers, stress, relationship quality, role captivity and caring competence. Results: The sample of people with dementia consisted of 20 minority ethnic and 60 white participants and for carers 15 and 45 respectively. People with dementia from minority ethnic groups had poorer quality of life (−4.74, 95% CI: −7.98 to −1.50) and higher loneliness (1.72, 95% CI: 0.78–2.66) whilst minority ethnic carers had higher stress (8.17, 95% CI: 1.72–14.63) and role captivity (2.00, 95% CI: 0.43–3.57) and lower relationship quality (−9.86, 95% CI: −14.24 to −5.48) than their white peers. Conclusion: Our exploratory study suggests that people with dementia from minority ethnic groups experience lower quality of life and carers experience higher stress and role captivity and lower relationship quality than their white peers. Confirmatory research with larger samples is required to facilitate analysis of the experiences of specific minority ethnic groups and examine the factors contributing to these disadvantages

Multi-Decadal Changes in Mangrove Extent, Age and Species in the Red River Estuaries of Viet Nam

This research investigated the performance of four different machine learning supervised image classifiers: artificial neural network (ANN), decision tree (DT), random forest (RF), and support vector machine (SVM) using SPOT-7 and Sentinel-1 images to classify mangrove age and species in 2019 in a Red River estuary, typical of others found in northern Viet Nam. The four classifiers were chosen because they are considered to have high accuracy, however, their use in mangrove age and species classifications has thus far been limited. A time-series of Landsat images from 1975 to 2019 was used to map mangrove extent changes using the unsupervised classification method of iterative self-organizing data analysis technique (ISODATA) and a comparison with accuracy of K-means classification, which found that mangrove extent has increased, despite a fall in the 1980s, indicating the success of mangrove plantation and forest protection efforts by local people in the study area. To evaluate the supervised image classifiers, 183 in situ training plots were assessed, 70% of them were used to train the supervised algorithms, with 30% of them employed to validate the results. In order to improve mangrove species separations, Gram–Schmidt and principal component analysis image fusion techniques were applied to generate better quality images. All supervised and unsupervised (2019) results of mangrove age, species, and extent were mapped and accuracy was evaluated. Confusion matrices were calculated showing that the classified layers agreed with the ground-truth data where most producer and user accuracies were greater than 80%. The overall accuracy and Kappa coefficients (around 0.9) indicated that the image classifications were very good. The test showed that SVM was the most accurate, followed by DT, ANN, and RF in this case study. The changes in mangrove extent identified in this study and the methods tested for using remotely sensed data will be valuable to monitoring and evaluation assessments of mangrove plantation projects

Loneliness and isolation among people with dementia and their carers: Prevalence, risk factors and a dyadic analysis

Poster presented at Alzheimer’s Association International Conference® 2020 (AAIC®) Meeting Abctracts: Dementia Care and Psychosocial Factors, streamed online, 27-31 July 2020, the Alzheimer's Association. Available free online at https://doi.org/10.1002/alz.041922.Background: People with dementia and their carers may be vulnerable to loneliness and isolation. We investigated: (a) prevalence of, and risk factors for, loneliness and isolation among people with dementia and their carers and (b) the interrelationship between loneliness and isolation for dyads (person with dementia and carer). Method: The IDEAL cohort of people with dementia and their carers includes two loneliness measures: the 6 item de Jong Gierveld (DJG) scale (range 0-6 and classified: not lonely (0-2), moderately lonely (3-4) and severely lonely (5+)) and a single-item question, plus a measure of social isolation, the six-item Lubben social network scale (range 0-30: not isolated (13+) or isolated (12 or less). For dyads consisting of a carer and a person with dementia, 1089 had complete data on loneliness and 1204 on social isolation. We report prevalence and examine loneliness/isolation risk factors using regression analysis for people with dementia and carers separately. We use Actor-Partner Interdependence Models (APIM) to examine the relationship between isolation and loneliness within dyads and vice-versa. Result: Prevalence of severe loneliness for people with dementia was 10% (single item score) and 5% (DJG score 5+) (15% and 18% respectively for carers). One third of people with dementia, 35%, were at risk of isolation (18% of carers). Social isolation was the only risk factor for loneliness consistent for both carers and people with dementia. Risk factors for loneliness in carers were caregiving stress and relationship quality and in people with dementia living alone, depression and life satisfaction/quality of life. Loneliness ratings were congruent in 43.1% of dyads (67.8% for isolation). Dyadic analysis using APIM demonstrates that loneliness is affected by both individuals’ own isolation and that of their partners.There were also actor and partner effects for the association between loneliness and isolation. Conclusion: Most people with dementia and their carers are neither lonely nor isolated. Risk factors for loneliness are different for carers and people with dementia. Isolation in the carers influences the loneliness of the person with dementia and vice versa.Economic and Social Research Council ref: ES/L001853/2 Improving the experience of Dementia and Enhancing Active Life: living well with dementia. The IDEAL study

Living well with dementia: An exploratory matched analysis of minority ethnic and white people with dementia and carers participating in the IDEAL programme

Data Availability Statement: IDEAL data were deposited with the UK data archive in April 2020. Details of how to access the data can be found here: https://reshare.ukdataservice.ac.uk/854317/.Copyright © 2024 The Authors. Objectives: The increasing heterogeneity of the population of older people is reflected in an increasing number of people with dementia and carers drawn from minority ethnic groups. Data from the IDEAL study are used to compare indices of ‘living well’ among people with dementia and carers from ethnic minority groups with matched white peers. Methods: We used an exploratory cross-sectional case-control design to compare ‘living well’ for people with dementia and carers from minority ethnic and white groups. Measures for both groups were quality of life, life satisfaction, wellbeing, loneliness, and social isolation and, for carers, stress, relationship quality, role captivity and caring competence. Results: The sample of people with dementia consisted of 20 minority ethnic and 60 white participants and for carers 15 and 45 respectively. People with dementia from minority ethnic groups had poorer quality of life (−4.74, 95% CI: −7.98 to −1.50) and higher loneliness (1.72, 95% CI: 0.78–2.66) whilst minority ethnic carers had higher stress (8.17, 95% CI: 1.72–14.63) and role captivity (2.00, 95% CI: 0.43–3.57) and lower relationship quality (−9.86, 95% CI: −14.24 to −5.48) than their white peers. Conclusion: Our exploratory study suggests that people with dementia from minority ethnic groups experience lower quality of life and carers experience higher stress and role captivity and lower relationship quality than their white peers. Confirmatory research with larger samples is required to facilitate analysis of the experiences of specific minority ethnic groups and examine the factors contributing to these disadvantages.Economic and Social Research Council; National Institute for Health and Care Research. Grant Number: ES/L001853/

Perspectives of Minority Ethnic Caregivers of People with Dementia Interviewed as Part of the IDEAL Programme

Data Availability: The data used to support the 8ndings of this study are available from the corresponding author upon reasonable request.Postwar migrants from the Caribbean and Indian subcontinent (Bangladesh, India, and Pakistan) to the UK are now experiencing the onset of age‐related diseases such as dementia. Our evidence base, both quantitative and qualitative, documenting the experiences of family caregivers of people with dementia is largely drawn from studies undertaken with white European, North American, and Australasian populations. Consequently, there is a need for research in the field of dementia caregiving to reflect the increasing diversity in ethnic identities of the older adult population of the UK. Using semistructured interviews, we investigated the experiences of 18 caregivers of people with dementia in Black Caribbean, Black African, and South Asian (Indian, Pakistani, and Bangladeshi) communities in England. Participants were recruited from the Join Dementia Research platform and were predominantly female intergenerational carers. We identified the following three themes: motivation to care (spending time with the care recipient and reciprocity), positive and negative consequences of caregiving (rewards and consequences), and the cultural context of caregiving (cultural norms and values supporting caregiving and negative attitudes towards dementia). Our findings develop existing literature by identifying (a) the importance of spending time with the person they care for, (b) the absence of faith as a caregiving driver, and (c) the challenge of watching the declining health of a parent. We highlight how the different motivations to care are intertwined and dynamic. This is illustrated by the linking of obligation and reciprocity in our dataset and positive and negative experiences of caregiving.Alzheimer's Society. Grant Numbers: 348, AS-PR2-16-001; National Institute for Health Researc