A new phosphate purification method for igneous weathering profiles.

RATIONALE: The oxygen isotope composition of phosphate (δ18 OPO4 ) is widely employed for reconstructing paleotemperature and tracing biogeochemical phosphorus cycling. However, existing phosphate purification protocols do not work well for igneous rocks and igneous weathering profiles (IWPs). A reliable purification method is needed for measuring δ18 OPO4 in these materials. METHODS: Our phosphate purification method includes two steps of cation exchange resin treatment separated by a step of calcium phosphate precipitation (R-Ca-R method). In addition, the silver phosphate precipitation in our procedure is featured by slow evaporation to crystallization until the appearance of ammonium nitrate or silver nitrate crystals. We evaluated our methods on weathered and pristine igneous rocks, phosphorite rocks, KH2 PO4 , and (NH4 )2 HPO4 solutions. RESULTS: Our purification method converted over 99.9% phosphate in solution to calcium phosphate, which can be easily decalcified by cation resin. The improved silver phosphate precipitation method produced high phosphate yields (97.1%-99.5%) and retained original δ18 OPO4 within analytical uncertainty (2σ = 0.6‰). We applied the purification and precipitation method on five igneous rocks and IWPs, and obtained δ18 OPO4 values ranging from 6.4‰ to 8.0‰. Duplicate phosphate extractions yielded δ18 OPO4 values differing by less than 0.3‰. CONCLUSIONS: We developed a new phosphate purification method that is applicable to phosphate extraction in igneous rocks and IWPs. We also proposed a reliable indicator for the termination of silver phosphate precipitation. Our method can achieve high phosphate yield and reproducible δ18 OPO4 value.

Barriers and facilitators to dementia care in long-term care facilities: protocol for a qualitative systematic review and meta-synthesis.

INTRODUCTION: Long-term care needs for people with dementia are predicted to increase due to increased life expectancy and dementia diagnoses. Most published meta- syntheses of dementia care focus on hospitals or home settings. When focusing on long-term care facilities, most reviews about dementia care only focus on a single outcome, such as feeding, behavioural symptoms management, palliative care and others, which is limited. The present study aims to synthesise qualitative data and examine barriers and facilitators to caring for people with dementia in long-term care facilities. METHODS AND ANALYSIS: This is the protocol for our systematic review and meta-synthesis, which describes the design of this study, and we plan to complete the study from October 2023 to November 2024. The systematic review and meta-synthesis will follow the Joanna Briggs Institute (JBI) guidance for systematic reviews of qualitative evidence. Nine databases (five English and four Chinese) were searched, including Embase, Web of Science, Medline, CINAHL, PsycINFO and Wan Fang Data, China National Knowledge Infrastructure, VIP and Chinese Biomedical Medicine, from inception to August 2023. Qualitative and mixed-approach research about barriers and facilitators to caring for people with dementia in long-term care facilities, which are reported in English or Chinese, will be included. Covidence software will help with study selection, assessment and data extraction. The JBI Critical Appraisal Checklist for Qualitative Research (2020) will be used for included studies' quality assessment. Data extraction will be based on the JBI Qualitative Assessment and Review Instrument Data Extraction Tool for Qualitative Research. The JBI aggregation approach will be used to synthesise data. We will use the JBI ConQual tool to assess the credibility and dependability of each synthesised finding to establish confidence in the synthesised findings. All review steps will be managed by two reviewers independently, and disparities will be discussed. If consensus cannot reach a resolution, a third reviewer will be consulted. ETHICS AND DISSEMINATION: The present study is a secondary analysis of published qualitative data. So ethical approval is not required. The findings may be disseminated through peer-reviewed publications, conference papers or elsewhere. PROSPERO REGISTRATION NUMBER: The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO) in May 2022, and the registration number is CRD42022326178.

The Effectiveness of Multi-Component Interventions on the Positive and Negative Aspects of Well-Being among Informal Caregivers of People with Dementia: A Systematic Review and Meta-Analysis.

The present review aims to examine whether multi-component interventions for informal caregivers of people with dementia are effective on positive and negative aspects of caregiver well-being. Eleven databases were searched from inception to 8 March 2021. Only randomized controlled trials reporting the effectiveness of multi-component intervention on positive and negative aspects of caregiver well-being were eligible. Endnote X7 (Thomson ResearchSoft, Stanford, CA, USA) was used for study selection and version 5.1.0 of Cochrane Collaboration's tool (Cochrane, London, UK) was applied for quality assessment. Review Manager (Revman) Version 5.3 (Cochrane, London, UK) was used for the meta-analysis, and if statistical synthesis was inappropriate, only narrative analysis was performed. A total of 31 RCTs with 3939 participants were included. Meta-analyses showed small to moderate effects on subjective well-being, depression, and burden of caregivers, and a moderate to high effect on caregiver anxiety. Due to insufficient data and vast heterogeneity, meta-analysis was not performed for other outcomes, such as resilience, competence, and empathy. This review suggests that individualized multi-component interventions for caregivers may be one of the ways to promote their well-being. Further research is needed to explore the impact of rigorously designed and personalized multi-component interventions on informal caregivers, especially on more positive indicators, as well as its long-term effects and sustainability.

New Ediacara fossils preserved in marine limestone and their ecological implications.

Ediacara fossils are central to our understanding of animal evolution on the eve of the Cambrian explosion, because some of them likely represent stem-group marine animals. However, some of the iconic Ediacara fossils have also been interpreted as terrestrial lichens or microbial colonies. Our ability to test these hypotheses is limited by a taphonomic bias that most Ediacara fossils are preserved in sandstones and siltstones. Here we report several iconic Ediacara fossils and an annulated tubular fossil (reconstructed as an erect epibenthic organism with uniserial arranged modular units), from marine limestone of the 551-541 Ma Dengying Formation in South China. These fossils significantly expand the ecological ranges of several key Ediacara taxa and support that they are marine organisms rather than terrestrial lichens or microbial colonies. Their close association with abundant bilaterian burrows also indicates that they could tolerate and may have survived moderate levels of bioturbation.