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Axially chiral arylpyrroles are key components of pharmaceuticals and natural products as well as chiral catalysts and ligands for asymmetric transformations. However, the catalytic enantioselective construction of optically active arylpyrroles remains a formidable challenge. Here we disclose a highly efficient strategy to access enantioenriched axially chiral arylpyrroles by means of organocatalytic atroposelective desymmetrization and kinetic resolution. Depending on the remote control of chiral catalyst, the arylpyrroles were obtained in high yields and excellent enantioselectivities under mild reaction conditions. This strategy tolerates a wide range of functional groups, providing a facile avenue to approach axially chiral arylpyrroles from simple and readily available starting materials. Selected arylpyrrole products proved to be efficient chiral ligands in asymmetric catalysis and also important precursors for further synthetic transformations into highly functionalized pyrroles with potential bioactivity, especially the axially chiral fully substituted arylpyrroles. Axially chiral arylpyrroles are structural motifs often found in natural and medicinal products. Here, the authors report the atroposelective synthesis of axially chiral arylpyrrole derivatives, which proved to be efficient chiral ligands for asymmetric catalysis, through desymmetrization and kinetic resolution.

The solid–electrolyte interphase (SEI) dictates the performance of most batteries, but the understanding of its chemistry and structure is limited by the lack of in situ experimental tools. In this work, we present a dynamic picture of the SEI formation in lithium-ion batteries using in operando liquid secondary ion mass spectrometry in combination with molecular dynamics simulations. We find that before any interphasial chemistry occurs (during the initial charging), an electric double layer forms at the electrode/electrolyte interface due to the self-assembly of solvent molecules. The formation of the double layer is directed by Li+ and the electrode surface potential. The structure of this double layer predicts the eventual interphasial chemistry; in particular, the negatively charged electrode surface repels salt anions from the inner layer and results in an inner SEI that is thin, dense and inorganic in nature. It is this dense layer that is responsible for conducting Li+ and insulating electrons, the main functions of the SEI. An electrolyte-permeable and organic-rich outer layer appears after the formation of the inner layer. In the presence of a highly concentrated, fluoride-rich electrolyte, the inner SEI layer has an elevated concentration of LiF due to the presence of anions in the double layer. These real-time nanoscale observations will be helpful in engineering better interphases for future batteries.An operando mass spectrometry technique, along with molecular dynamics simulations, unveils the evolution of the solid–electrolyte interphase chemistry and structure in lithium-ion batteries during the first cycle.

• Plant microbiomes are essential to host health and productivity but the ecological processes that govern crop microbiome assembly are not fully known. • Here we examined bacterial communities across 684 samples from soils (rhizosphere and bulk soil) and multiple compartment niches (rhizoplane, root endosphere, phylloplane, and leaf endosphere) in maize (Zea mays)-wheat (Triticum aestivum)/barley (Hordeum vulgare) rotation system under different fertilization practices at two contrasting sites. • Our results demonstrate that microbiome assembly along the soil-plant continuum is shaped predominantly by compartment niche and host species rather than by site or fertilization practice. From soils to epiphytes to endophytes, host selection pressure sequentially increased and bacterial diversity and network complexity consequently reduced, with the strongest host effect in leaf endosphere. Source tracking indicates that crop microbiome is mainly derived from soils and gradually enriched and filtered at different plant compartment niches. Moreover, crop microbiomes were dominated by a few dominant taxa (c. 0.5% of bacterial phylotypes), with bacilli identified as the important biomarker taxa for wheat and barley and Methylobacteriaceae for maize. • Our work provides comprehensive empirical evidence on host selection, potential sources and enrichment processes for crop microbiome assembly, and has important implications for future crop management and manipulation of crop microbiome for sustainable agriculture.

Key Points Metagenome-wide association studies (MWAS) of human disease are now possible, owing to advances in DNA sequencing and the development of reference gene catalogues and gene clustering methods. MWAS have identified associations between the microbiome and several major diseases, despite the relatively small sample sizes that have been examined by these studies compared with genome-wide association studies (GWAS). Common changes to the taxa and functions of the gut microbiota have emerged from MWAS of metabolic diseases. To advance from the detection of associations to the demonstration that elements of the microbiota contribute to disease will require a range of validations, including mechanistic studies both in vivo and in vitro . However, even associations that are shown to be non-causal could form the basis of diagnostic markers. In the future, MWAS may be further developed in numerous ways, including the use of multiomic data, the analysis of genetic variants in metagenomic data and the study of the non-bacterial components of the microbiome. Metagenome-wide association studies (MWAS) are designed to detect associations between the human microbiome and disease. In this Review, Jia and Wang describe the principal findings of MWAS of human diseases, and consider how these findings might be integrated into medical research and practice. Metagenome-wide association studies (MWAS) have enabled the high-resolution investigation of associations between the human microbiome and several complex diseases, including type 2 diabetes, obesity, liver cirrhosis, colorectal cancer and rheumatoid arthritis. The associations that can be identified by MWAS are not limited to the identification of taxa that are more or less abundant, as is the case with taxonomic approaches, but additionally include the identification of microbial functions that are enriched or depleted. In this Review, we summarize recent findings from MWAS and discuss how these findings might inform the prevention, diagnosis and treatment of human disease in the future. Furthermore, we highlight the need to better characterize the biology of many of the bacteria that are found in the human microbiota as an essential step in understanding how bacterial strains that have been identified by MWAS are associated with disease.

China faces the greatest challenge from stroke in the world. The death rate for cerebrovascular diseases in China was 149.49 per 100 000, accounting for 1.57 million deaths in 2018. It ranked third among the leading causes of death behind malignant tumours and heart disease. The age-standardised prevalence and incidence of stroke in 2013 were 1114.8 per 100 000 population and 246.8 per 100 000 person-years, respectively. According to the Global Burden of Disease Study 2017, the years of life lost (YLLs) per 100 000 population for stroke increased by 14.6%; YLLs due to stroke rose from third highest among all causes in 1990 to the highest in 2017. The absolute numbers and rates per 100 000 population for all-age disability-adjusted life years (DALYs) for stroke increased substantially between 1990 and 2017, and stroke was the leading cause of all-age DALYs in 2017. The main contributors to cerebrovascular diseases include behavioural risk factors (smoking and alcohol use) and pre-existing conditions (hypertension, diabetes mellitus, dyslipidaemia and atrial fibrillation (AF)). The most prevalent risk factors among stroke survivors were hypertension (63.0%-84.2%) and smoking (31.7%-47.6%). The least prevalent was AF (2.7%-7.4%). The prevalences for major risk factors for stroke are high and most have increased over time. Based on the latest national epidemiological data, 26.6% of adults aged ≥15 years (307.6 million adults) smoked tobacco products. For those aged ≥18 years, age-adjusted prevalence of hypertension was 25.2%; adjusted prevalence of hypercholesterolaemia was 5.8%; and the standardised prevalence of diabetes was 10.9%. For those aged ≥40 years, the standardised prevalence of AF was 2.31%. Data from the Hospital Quality Monitoring System showed that 3 010 204 inpatients with stroke were admitted to 1853 tertiary care hospitals during 2018. Of those, 2 466 785 (81.9%) were ischaemic strokes (ISs); 447 609 (14.9%) were intracerebral haemorrhages (ICHs); and 95 810 (3.2%) were subarachnoid haemorrhages (SAHs). The average age of patients admitted was 66 years old, and nearly 60% were male. A total of 1555 (0.1%), 2774 (0.6%) and 1347 (1.4%) paediatric strokes (age <18 years) were identified among IS, ICH and SAH, respectively. Over one-third (1 063 892 (35.3%)) of the patients were covered by urban resident basic medical insurance, followed by urban employee basic medical insurance (699 513 (23.2%)) and new rural cooperative medical schema (489 361 (16.3%)). The leading risk factor was hypertension (67.4% for IS, 77.2% for ICH and 49.1% for SAH), and the leading comorbidity was pneumonia or pulmonary infection (10.1% for IS, 31.4% for ICH and 25.2% for SAH). In-hospital death/discharge against medical advice rate was 8.3% for stroke inpatients, ranging from 5.8% for IS to 19.5% for ICH. The median and IQR of length of stay was 10.0 (7.0–14.0) days, ranging from 10.0 (7.0–13.0) in IS to 14.0 (8.0–22.0) in SAH. Data from the Chinese Stroke Center Alliance demonstrated that the composite scores of guideline-recommended key performance indicators for patients with IS, ICH and SAH were 0.77±0.21, 0.72±0.28 and 0.59±0.32, respectively.