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Observations have demonstrated an unstable interannual relationship between El Niño/Southern Oscillation (ENSO) and the East Asian winter monsoon in recent decades due to internal variability. However, it remains unclear whether the interannual ENSO‐East Asian winter monsoon relationship (EER) may change with long‐term external forcings, especially when they vary substantially. The results of a set of transient simulations during the last 21,000 years demonstrate the EER is enhanced during the Last Glacial Maximum relative to the Holocene, characterized by a poleward migration of ENSO's signal over the northwest Pacific. The strengthened EER results from the weakened interannual ENSO‐Aleutian Low teleconnection and the northeastward displacement of the climatological Aleutian Low, ultimately forced by the massive North American ice sheets at that time. Our study suggests a changing EER with various external forcings and implies potential uncertainty in applying the present‐day ENSO teleconnections during glacials. Plain Language Summary: The East Asian winter monsoon (EAWM) exerts significant impacts on the climate over Asia and affects billions of people; thus, a precise EAWM prediction is urgently required. Since the El Niño/South Oscillation (ENSO) provides the majority of skillful predictability, the effect of ENSO on EAWM has received considerable attention. Although recent studies noticed that the ENSO‐EAWM relationship (EER) was unstable during recent decades due to the oceanic oscillations, such as the Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation, it remains unclear whether the EER could change with substantially varied external forcings in the future, such as solar insolation, greenhouse gases, meltwater flux, and ice sheets. Using a set of transient simulations during the last 21,000 years, we found that the EER is significantly strengthened during the Last Glacial Maximum and early deglaciation relative to the Holocene, attributed to the vast North American ice sheets at that time. Therefore, this study will not only have great significance for the paleoclimate research, which usually applied the present‐day ENSO teleconnection to explain past changes in regional climate directly, but also help to project the future EER variation for a better EAWM prediction. Key Points: The ENSO‐East Asian winter monsoon relationship (EER) is significantly strengthened during the Last Glacial Maximum and early deglaciationThe strengthened EER is characterized by the poleward shift of ENSO's influence over the northwest PacificLarge North American ice sheets are the ultimate driver of the strengthened EER at that time [ABSTRACT FROM AUTHOR]

Background: While there is increasing knowledge about the gut microbiome, the factors influencing and the significance of the gut resistome are still not well understood. Infant gut commensals risk transferring multidrug-resistant antibiotic resistance genes (ARGs) to pathogenic bacteria. The rapid spread of multidrug-resistant pathogenic bacteria is a worldwide public health concern. Better understanding of the naïve infant gut resistome may build the evidence base for antimicrobial stewardship in both humans and in the food industry. Given the high carriage rate of extended spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in Asia, we aimed to evaluate community prevalence, dynamics, and longitudinal changes in antibiotic resistance gene (ARG) profiles and prevalence of ESBL-producing E. coli and K. pneumoniae in the intestinal microbiome of infants participating in the Growing Up in Singapore Towards Healthy Outcomes (GUSTO) study, a longitudinal cohort study of pregnant women and their infants.Methods: We analysed ARGs in the first year of life among 75 infants at risk of eczema who had stool samples collected at multiple timepoints using metagenomics.Results: The mean number of ARGs per infant increased with age. The most common ARGs identified confer resistance to aminoglycoside, beta-lactam, macrolide and tetracycline antibiotics; all infants harboured these antibiotic resistance genes at some point in the first year of life. Few ARGs persisted throughout the first year of life. Beta-lactam resistant Escherichia coli and Klebsiella pneumoniae were detected in 4 (5.3%) and 32 (42.7%) of subjects respectively.Conclusion: In this longitudinal cohort study of infants living in a region with high endemic antibacterial resistance, we demonstrate that majority of the infants harboured several antibiotic resistance genes in their gut and showed that the infant gut resistome is diverse and dynamic over the first year of life. [ABSTRACT FROM AUTHOR]

The East Asian summer monsoon affects precipitation and hence vegetation in the densely populated Northwest Pacific region, yet a long-standing controversy exists concerning the spatial and temporal dynamics of the Holocene Optimum (HO) in the East Asian Monsoon Region. Here we use a detailed 14,000-year record reconstructing vegetation variations from a strategically selected crater lake from Northeast China, as well as a compilation of previous paleoclimatic studies, to show that the HO began around 6,000 Cal a BP in Northeast China, significantly later than generally recognized. By comparing our paleoenvironmental data with Holocene vegetation records from other regions of East Asia, we identified a marked northward shift for the onset of the HO from ∼ 10 , 260 Cal a BP in South China to ∼ 6 , 000 Cal a BP in Northeast China. The gradual northward transgression of the vegetation change could be caused by both the temperature and precipitation changes in different regions. Finally, we fitted a regression model of the start of the HO period versus latitude, which allowed us to make predictions for the beginning of the HO at different geographical locations. This study reveals a strong relationship between latitude and the initiation of the HO, and provides a window towards better understanding the forcing of vegetation changes in the East Asian monsoon region. [ABSTRACT FROM AUTHOR]