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Tropical cyclones (TCs) over the Bay of Bengal (BOB) can interact with the South Branch Trough (SBT) as they move northward and potentially amplify Rossby waves. This study evaluates the features of Rossby waves and their downstream impact on rainfall in South China. Results indicate that TC‐SBT interactions primarily occur in May and October‐November (Oct‐Nov), with probabilities of 59% and 53% respectively. Notably, the Rossby wave train associated with BOB TCs is more pronounced during Oct‐Nov due to the stronger subtropical westerly jet, in contrast to May. The downstream atmospheric response results in positive (negative) rainfall anomalies over South China in May (Oct‐Nov), particularly on the day following the maximum interaction day. Previous researches concerning TC‐extratropical flow interaction mainly focus on other basins where TCs move to higher latitudes, this study provides fresh insights into Rossby waves related to TC‐SBT interactions over the southern Tibetan Plateau. Plain Language Summary: During bimodal periods of tropical cyclone (TC) activity over the Bay of Bengal (BOB) in May and October‐November (Oct‐Nov), the Asian subtropical westerly jet is usually located at lower latitudes over the southern Tibetan Plateau, where South Branch Trough (SBT) is active. We quantified the extent of BOB TC‐SBT interaction based on the negative potential vorticity advection by TC‐associated irrotational wind. The mean location of the TC center and maximum interaction point are around (20°N, 88°E) and (33°N, 89°E), respectively. Rossby wave trains (RWT) associated with BOB TCs may extend eastward to 150°W, dispersing at a faster zonal group speed in May compared to Oct‐Nov. In May, the downstream response in South China featured by amplified upper‐level divergent outflow, intensified mid‐level warm and cold air convergence, and enhanced low‐level southwesterly water vapor transport, which was conducive to precipitation. In Oct‐Nov, the RWT shifted northward and the anticyclone anomaly related to the subtropical high dominated South China, leading to a northward shift in water vapor transport, unfavorable for precipitation in South China. The results are significant for the short‐ to medium‐range weather forecasts in downstream regions of BOB TCs. Key Points: Tropical cyclones (TC) over the Bay of Bengal (BOB) interacting with the South Branch Trough (SBT) can amplify mid‐latitude Rossby wavesThe Rossby wave associated with interactions between BOB TCs and SBTs is stronger in October‐November than in MayThe atmospheric response results in positive (negative) precipitation anomalies over South China in May (October‐November) [ABSTRACT FROM AUTHOR]

This first multi‐year investigation focuses on bores over the southern North China Plain during the 2015–2019 warm seasons. Bore structure depended on location with undular bores tending to occur close to the coast and non‐undular bores to the west near elevated terrain. Bores were most likely to occur during June and July when convection is active. While bore frequency over the Southern Great Plains (SGP) of U.S. is linked to the region's nocturnal low‐level jet, the bores herein were sensitive to the synoptic regime with ∼80% occurring during 4‐to‐5‐day periods under three different synoptic regimes. The bores had shorter durations than their SGP counterparts and a far wider range in their direction of propagation. Overall, these findings find regional differences in bores' frequency, movement, and structure serving an impetus for future investigations of nocturnal mesoscale convective systems and bores over China and other locations worldwide. Plain Language Summary: Mesoscale convective systems (MCSs) contribute to beneficial rainfall and the increase of extreme rainfall observed in present warming climate. MCSs are generally considered to be a result of lifting of the environmental air by the MCS's diabatically generated cold pool. Recent studies have shown that nocturnal MCSs can also generate bores that cause significant lifting (of ∼1 km) in the lower troposphere, destabilizing large areas (>10,000 km2) surrounding the MCS. Past studies of bores have generally concentrated on nocturnal convection over the Southern Great Plains (SGP) in the United States. This study provides the first systematic investigation of the generation, characteristics, and evolution of bores over China. While similarities were found with their SGP counterparts, the documentation of significant differences raises the impetus for future investigations focused on advancing the understanding and prediction of bore dynamics over other locations and their relationship to nocturnal mesoscale convective systems. Key Points: This climatological study examines the frequency, structure, and movement of bores over the southern North China PlainNocturnal mesoscale convective systems over China generate bores but with significant differences from that over the central United StatesThis study raises the impetus for future investigations of bores' dynamics and bores over other regions [ABSTRACT FROM AUTHOR]

The popular distilled Chinese strong-flavour liquor (CSFL) is produced by solid fermentation in the ground pit. Microbes inhabiting in the pit mud (PM) on the walls of the fermentation pit are responsible for the production of caproic acid (CA) that determines the quality of CSFL to a large degree. However, little is known about the active microbial populations and metabolic potential of the PM microbiome. Here, we investigated the overall metabolic features of the PM microbiome and its active microbial components by combining metagenomics and MiSeq-sequencing analyses of the 16S rRNA genes from DNA and RNA (cDNA). Results showed that prokaryotes were predominant populations in the PM microbiome, accounting for 95.3% of total metagenomic reads, while eukaryotic abundance was only 1.8%. The dominant prokaryotic phyla were Firmicutes, Euryarchaeota, Bacteroidetes, Actinobacteria and Proteobacteria, accounting for 48.0%, 19.0%, 13.5%, 2.5% and 2.1% of total metagenomic reads respectively. Most genes encoding putative metabolic pathways responsible for the putative CA production via chain elongation pathway were detected. This indicated that the PM microbiome owned functional potential for synthesizing CA from ethanol or lactate. Some key genes encoding enzymes involved in hydrogenotrophic and acetoclastic methanogenesis pathways were detected in the PM metagenome, suggesting the possible occurrence of interspecies hydrogen transfer between CA-producing bacteria and methanogens. The 16S rDNA and 16S rRNA profiles showed that the Clostridial cluster IV, Lactobacillus, Caloramator, Clostridium, Sedimentibacter, Bacteroides and Porphyromonas were active populations in situ, in which Clostridial cluster IV and Clostridium were likely involved in the CA production. This study improved our understandings on the active populations and metabolic pathways of the PM microbiome involved in the CA synthesis in the CSFL fermentation. [ABSTRACT FROM AUTHOR]

An invasive alien weed, Ageratina adenophora, has become widespread in the southwest of China due to its high environmental adaptation. In the present study, in order to understand the molecular aspects of resistance to heat and cold stress, we investigated the characterization and expression of heat shock protein genes (designated as Aahsp70 and Aahsp90) in A. adenophora. The cDNA of A. adenophora Aahsp70 and Aahsp90 was cloned by the combination of homology cloning and rapid amplification of cDNA ends (RACE). The Basic Local Alignment Search Tool analyses revealed that Aahsp70 and Aahsp90 shared high levels of identity with corresponding proteins from other species. Hybridization was employed to examine the expression patterns of Aahsp70 and Aahsp90. The relative expression levels of the Aahsp70 and Aahsp90 transcripts were both up-regulated and reached maximal levels at 2–4 h after heat shock. Then, Aahsp70 dropped progressively to the original level at ∼4 h after heat shock. The transcriptional changes of Aahsp70 and Aahsp90 both were more obvious under cold stress. Recombinant Aahsp70 and Aahsp90 improved the viability, in comparison with the control cultures, of Escherichia coli under stress conditions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the cell lysates suggested that the protective effect in vivo was related to increased thermo-stability of the soluble cytosolic proteins. This study emphasizes that the relationship between, and regulation of, heat shock proteins might incorporate variable strengths to increase the adaptation of A. adenophora. [ABSTRACT FROM AUTHOR]

Aims: To investigate the clinical characteristics and sera anti-aquaporin 4 (AQP4) antibody positivity in patients with inflammatory demyelinating disorders (IDDs) of the central nervous system (CNS) in Tianjin, China., Methods: We retrospectively evaluated 234 patients with IDDs including neuromyelitis optica (NMO), recurrent optic neuritis (rON), longitudinally extensive transverse myelitis (LETM), clinically isolated syndrome (CIS), and multiple sclerosis (MS) groups. Sera from 217 patients were determined for AQP4-Ab. The clinical characteristics and sera anti-AQP4 positivity were compared., Results: The IDDS comprised 63 MS, 51 NMO, 56 LETM, 10 rON, and 54 CIS. Compared with MS, NMO had a higher frequency of occurrence in women, intractable hiccup and nausea (IHN), medullospinal lesion, longitudinally extensive spinal cord lesions (LESCL) and bilateral ON, disease onset at a later age, and worsening residual disability. AQP4-Ab-positive rates were 84.1% and 69% in NMO and NMO spectrum disorders (NMOSD), respectively, whereas it was undetectable in all of the MS sera samples., Conclusions: We comprehensively contrast the distinct clinical features of MS, NMO, and NMOSD in our center. A sensitive AQP4-Ab assay is necessary for the early diagnosis of NMOSD in our patients. Neither medullospinal lesion nor IHN is unique in NMO., (© 2013 John Wiley & Sons Ltd.)