We explore the representation of the Atlantic Meridional Overturning Circulation (AMOC) in 27 models from the CMIP6 multimodel ensemble. Comparison with RAPID and SAMBA observations suggests that the ...ensemble mean represents the AMOC strength and vertical profile reasonably well. Linear trends over the entire historical period (1850–2014) are generally neutral, but many models exhibit an AMOC peak around the 1980s. Ensemble mean AMOC decline in future (SSP) scenarios is stronger in CMIP6 than CMIP5 models. In fact, AMOC decline in CMIP6 is surprisingly insensitive to the scenario at least up to 2060. We find an emergent relationship among a majority of models between AMOC strength and 21st century AMOC decline. Constraining this relationship with RAPID observations suggests that the AMOC might decline between 6 and 8 Sv (34–45%) by 2100. A smaller group of models projects much less AMOC weakening of only up to 30%.
Plain Language Summary
The Atlantic Meridional Overturning Circulation (AMOC) is a circulation pattern in the Atlantic Ocean that is an important component of the climate system, due to its ability to redistribute and sequester heat and carbon. An accurate representation of the AMOC is a critical test for climate models and essential for building confidence in their projections. Here we investigate the AMOC in 27 climate models that contributed simulations to the Coupled Model Intercomparison Project Phase 6 (CMIP6). We find that many models reproduce the observed AMOC quite well, but there are still several models in which the AMOC is too weak or too strong. Most models suggest a slight upward trend in the AMOC from 1850 to the 1980s. Simulations representing different scenarios for future socioeconomic development suggest a stronger AMOC decline compared to previous assessments. Using direct measurements of the AMOC since 2004 and an emerging across‐model relationship between AMOC decline in the 21st century and their present‐day mean state, we find that the majority of CMIP6 models point to an end of century AMOC weakening of 34–45% of its present‐day strength. A smaller group of models projects much less weakening of only up to 30% of its present state.
Key Points
AMOC mean strength is well reproduced by the CMIP6 multimodel mean, but large model spread persists
Projected AMOC decline by the end of the 21st century shows weak dependence on the SSP scenarios
An emergent constraint between AMOC strength and projected decline suggests possible AMOC decline between 34% and 45% by 2100
Exploring efficient electrocatalysts for lithium–sulfur (Li–S) batteries is of great significance for the sulfur/polysulfide/sulfide multiphase conversion. Herein, we report nickel–iron intermetallic ...(Ni3Fe) as a novel electrocatalyst to trigger the highly efficient polysulfide-involving surface reactions. The incorporation of iron into the cubic nickel phase can induce strong electronic interaction and lattice distortion, thereby activating the inferior Ni phase to catalytically active Ni3Fe phase. Kinetics investigations reveal that the Ni3Fe phase promotes the redox kinetics of the multiphase conversion of Li–S electrochemistry. As a result, the Li–S cells assembled with a 70 wt % sulfur cathode and a Ni3Fe-modified separator deliver initial capacities of 1310.3 mA h g–1 at 0.1 C and 598 mA h g–1 at 4 C with excellent rate capability and a long cycle life of 1000 cycles at 1 C with a low capacity fading rate of ∼0.034 per cycle. More impressively, the Ni3Fe-catalyzed cells exhibit outstanding performance even at harsh working conditions, such as high sulfur loading (7.7 mg cm–2) or lean electrolyte/sulfur ratio (∼6 μL mg–1). This work provides a new concept on exploring advanced intermetallic catalysts for high-rate and long-life Li–S batteries.
Objectives To summarise evidence on the association between white rice consumption and risk of type 2 diabetes and to quantify the potential dose-response relation.Design Meta-analysis of prospective ...cohort studies.Data sources Searches of Medline and Embase databases for articles published up to January 2012 using keywords that included both rice intake and diabetes; further searches of references of included original studies.Study selection Included studies were prospective cohort studies that reported risk estimates for type 2 diabetes by rice intake levels.Data synthesis Relative risks were pooled using a random effects model; dose-response relations were evaluated using data from all rice intake categories in each study.Results Four articles were identified that included seven distinct prospective cohort analyses in Asian and Western populations for this study. A total of 13 284 incident cases of type 2 diabetes were ascertained among 352 384 participants with follow-up periods ranging from 4 to 22 years. Asian (Chinese and Japanese) populations had much higher white rice consumption levels than did Western populations (average intake levels were three to four servings/day versus one to two servings/week). The pooled relative risk was 1.55 (95% confidence interval 1.20 to 2.01) comparing the highest with the lowest category of white rice intake in Asian populations, whereas the corresponding relative risk was 1.12 (0.94 to 1.33) in Western populations (P for interaction=0.038). In the total population, the dose-response meta-analysis indicated that for each serving per day increment of white rice intake, the relative risk of type 2 diabetes was 1.11 (1.08 to 1.14) (P for linear trend<0.001).Conclusion Higher consumption of white rice is associated with a significantly increased risk of type 2 diabetes, especially in Asian (Chinese and Japanese) populations.
A new data-driven computational framework is developed to assist in the design and modeling of new material systems and structures. The proposed framework integrates three general steps: (1) design ...of experiments, where the input variables describing material geometry (microstructure), phase properties and external conditions are sampled; (2) efficient computational analyses of each design sample, leading to the creation of a material response database; and (3) machine learning applied to this database to obtain a new design or response model.
In addition, the authors address the longstanding challenge of developing a data-driven approach applicable to problems that involve unacceptable computational expense when solved by standard analysis methods – e.g. finite element analysis of representative volume elements involving plasticity and damage. In these cases the framework includes the recently developed “self-consistent clustering analysis” method in order to build large databases suitable for machine learning. The authors believe that this will open new avenues to finding innovative materials with new capabilities in an era of high-throughput computing (“big-data”).
•Unified data-driven framework for design and modeling of materials and structures.•Integration of design of experiments, computational analyses, and machine learning.•Avoids curse of dimensionality when using self-consistent clustering analyses method.
Capacitive power transfer (CPT) based on electric field coupling has been proposed recently as an alternative technology for wireless power transfer, and a good understanding of the capacitive ...coupling is of great importance in the design and evaluation of CPT systems. A new term named capacitive coupling coefficient kE is introduced to provide a quantitative measure of the coupling condition between the coupling plates. The term is derived by modelling the capacitive coupling plates based on electric charge balance, and its physical meaning is explained clearly in relation to the equivalent primary/secondary and mutual capacitances, which is also experimentally demonstrated by comparing two CPT systems with different cross-coupling configurations.
The search for effective COVID-19 management strategies continues to evolve. Current understanding of SARS-CoV-2 mechanisms suggests a central role for exaggerated activation of the innate immune ...system as an important contributor to COVID-19 adverse outcomes. The actions of colchicine, one of the oldest anti-inflammatory therapeutics, target multiple mechanisms associated with COVID-19 excessive inflammation. While many COVID-19 trials have sought to manipulate SARS-CoV-2 or dampen the inflammatory response once patients are hospitalised, few examine therapeutics to prevent the need for hospitalisation. Colchicine is easily administered, generally well tolerated and inexpensive, and holds particular promise to reduce the risk of hospitalisation and mortality due to COVID-19 in the outpatient setting. Successful outpatient treatment of COVID-19 could greatly reduce morbidity, mortality and the demand for rare or expensive care resources (front-line healthcare workers, hospital beds, ventilators, biological therapies), to the benefit of both resource-replete and resource-poor regions.
Green supply chain management has emerged as a proactive approach for
improving environmental performance of processes and products in
accordance with the requirements of environmental regulations. ...Various
approaches for implementing green supply chain management practices has
been proposed and recognized in previous literatures, yet no
investigation has identified the reliability and validity of such
approaches particularly in electronic industry. This study examines the
consistency approaches by factor analysis that determines the adoption
and implementation of green supply chain management in Taiwanese
electronic industry. The fuzzy analytic hierarchy process method is
applied to prioritize the relative importance of four dimensions and
twenty approaches among nine enterprises in electronic industry. The
findings indicate that these enterprises would emphasize on supplier
management performance in the crucial role of implementing green supply
chain management. Establishing an environmental database of products,
asking for product testing report and top management support are among
the most important approaches. The results for the implications of
green supply chain management implementation in electronic industry
investigated in this work generate a generic hierarchy model for
decision-makers who can prioritize those approaches for implementing
green supply chain management in Taiwan.
The gut is composed of a single layer of intestinal epithelial cells and plays important roles in the digestion and absorption of nutrients, immune and barrier functions and amino acid metabolism. ...Weaning stress impairs piglet intestinal epithelium structural and functional integrities, which results in reduced feed intake, growth rates and increased morbidity and mortality. Several measures are needed to maintain swine gut development and growth performance after weaning stress. A large body of evidence indicates that, in weaning piglets, glutamine, a functional amino acid, may improve growth performance and intestinal morphology, reduce oxidative damage, stimulate enterocyte proliferation, modulate cell survival and death and enhance intestinal paracellular permeability. This review focuses on the effects of glutamine on intestinal health in piglets. The aim is to provide evidentiary support for using glutamine as a feed additive to alleviate weaning stress.
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