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Knowledge of the paleoclimatic record of the northeastern Tibetan Plateau (NETP) can potentially improve our understanding of the evolution of the Asian summer monsoon (ASM). However, the history of climate change and inferred spatial extent of the ASM on the NETP since the last deglaciation remain unclear. Here, we use several environmental proxies from the sediments of Hala Lake (beyond the modern limit of ASM), including chironomids, loss‐on‐ignition, grain size and element data, to explore the climatic history of the NETP and the northern boundary of the ASM since the last deglaciation. The results document a series of climatic events during the deglaciation, including Heinrich Event 1, the Bølling–Allerød interstadial and the Younger Dryas event. The records also reveal the timing of the megathermal and precipitation maximum, the lake‐level maximum, and strongest chemical weathering, which occurred during ~10–7 ka. The inferred precipitation maximum during the early Holocene in the Hala Lake basin, which can be verified by the simulated precipitation change, is consistent with that in typical Indian summer monsoon (ISM) regions, suggesting that the ISM has penetrated into Hala Lake basin at that time. The monsoon‐dominated climate in the Hala Lake basin during the early Holocene and the westerlies‐dominated climate in the arid central Asia indicate that the maximum areal extent of the ASM on the NETP since the last deglaciation lay to the northwest of Hala Lake basin. In combination with other published records, the northernmost boundary of the ASM over China since the last deglaciation has been tentatively delineated, to shed some lights on this long‐standing debate. [ABSTRACT FROM AUTHOR]

Subfossil Pediastrum , a genus of green algae (Chlorophyceae) which is sensitive to changes in the aquatic environment, is a potential proxy indicator of the evolution of aquatic ecosystems and climate change. We synthesized subfossil Pediastrum records from arid central Asia (ACA) and the Asian summer monsoon (ASM) region in order to characterize their hydro-climatic evolution during the Holocene. In ACA, low concentrations of subfossil Pediastrum during the early Holocene resulted from the higher salinity caused by a dry climate or lower lake levels. The increasing trend of subfossil Pediastrum content during the middle-late Holocene is consistent with the occurrence of wetter regional climatic conditions. In the marginal areas of the Asian summer monsoon (MASM) region of northern China, the variations in subfossil Pediastrum concentration coincide with increased summer monsoon rainfall during the middle Holocene, but concentrations were generally lower during the late Holocene as a result of increased salinity or alkalinity associated with a weakened summer monsoon. In the Tibetan Plateau, the variations in subfossil Pediastrum abundance are more complicated due to divergent moisture/precipitation patterns influenced by both the ASM and the mid-latitude westerlies. In the Indian summer monsoon-dominated region, subfossil Pediastrum abundance was high during the early Holocene and then gradually decreased after ~8 cal kyr BP. The observed asynchronous changes in subfossil Pediastrum in ACA and the MASM region during the Holocene may reflect the specific moisture/precipitation patterns of the monsoon- or westerlies-dominated climatic regimes. We suggest that high evaporation in arid and semi-arid areas would have rapidly increased the salinity and/or alkalinity of lakes, while aquatic environments may have been more stable in more humid areas. • Synthesis of Holocene subfossil Pediastrum records from ACA and the MASM region. • Asynchronous Holocene hydro-climatic evolution of ACA and the MASM region. • Pediastrum abundance is a potential moisture proxy in arid and semi-arid areas. [ABSTRACT FROM AUTHOR]

Importance: Catheter ablation for persistent atrial fibrillation (AF) has shown limited success., Objective: To determine whether AF drivers could be accurately identified by periodicity and similarity (PRISM) mapping ablation results for persistent AF when added to pulmonary vein isolation (PVI)., Design, Setting, and Participants: This prospective randomized clinical trial was performed between June 1, 2019, and December 31, 2020, and included patients with persistent AF enrolled in 3 centers across Asia. Data were analyzed on October 1, 2022., Intervention: Patients were assigned to the PRISM-guided approach (group 1) or the conventional approach (group 2) at a 1:1 ratio., Main Outcomes and Measures: The primary outcome was freedom from AF or other atrial arrhythmia for longer than 30 seconds at 6 and 12 months., Results: A total of 170 patients (mean [SD] age, 62.0 [12.3] years; 136 men [80.0%]) were enrolled (85 patients in group 1 and 85 patients in group 2). More group 1 patients achieved freedom from AF at 12 months compared with group 2 patients (60 [70.6%] vs 40 [47.1%]). Multivariate analysis indicated that the PRISM-guided approach was associated with freedom from the recurrence of atrial arrhythmia (hazard ratio, 0.53 [95% CI, 0.33-0.85])., Conclusions and Relevance: The waveform similarity and recurrence pattern derived from high-density mapping might provide an improved guiding approach for ablation of persistent AF. Compared with the conventional procedure, this novel specific substrate ablation strategy reduced the frequency of recurrent AF and increased the likelihood of maintenance of sinus rhythm., Trial Registration: ClinicalTrials.gov Identifier: NCT05333952.