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Both South Asia and East Asia are the most polluted regions of the world. Unlike East Asia, the aerosol optical depth (AOD) over South Asia keeps increasing for all recent years, which calls for more attention. This study investigates the impacts of anthropogenic emissions over South Asia on the downstream regional climate during spring with the Community Earth System Model 2 (CESM2). The model results suggest that South Asian pollutants have significant impacts on East Asian spring climate, and the impacts could be even larger than locally emitted aerosols. Two possible dynamical pathways (i.e., the northern and the southern pathways) bridging South Asian aerosol forcing and East Asian climate are proposed, and both ways are associated with the black carbon (BC)-induced climate feedbacks surrounding the Tibetan Plateau (TP). The northern pathway is mainly due to the TP warming induced by the BC snow darkening effect (SDE), which significantly reduces the surface air temperature (SAT) over northern East Asia. BC-induced TP warming increases the meridional thermal gradient and accelerates the midlatitude jet stream, which favors the cold-air advection over northern East Asia. The southern pathway is associated with the BC "elevated heat pump" hypothesis, which mainly affects the precipitation in southern East Asia. BC from South Asia accumulates near the south slope of TP, inducing an abnormal ascending motion near the Bay of Bengal. A compensating anomalous sinking motion is then forced in South China, which suppresses the precipitation there. A primary observational analysis is also performed to verify both dynamical pathways. [ABSTRACT FROM AUTHOR]

Hosts defend against parasites through two main strategies: resistance and tolerance. These two strategies have different influences on the parasite load of the host and so have variable effects on the fitness of parasites. In this study, we investigated the strategy used by the Barn Swallow (Hirundo rustica) to defend against a hematophagous mite (Dermanyssus hirundinis) in East Asia. For the first time, we found Barn Swallows were parasitized by D. hirundinis in Asia and, in northeastern China, over 60% of broods were parasitized. We examined whether swallows with better body condition or the males with more extravagant sexually selected traits (longer tail streamers or redder ventral plumage) showed stronger resistance or tolerance to these parasites. The results showed that males with more extravagant sexual ornaments had weaker resistance (heavier brood mite load) than males with less extravagant traits; however, the heavier mite load was likely to be a byproduct of larger brood size. Moreover, the Barn Swallow population showed strong tolerance against the parasite (i.e. the brood mite load did not affect brood size or nestling body mass). It is worth noting that male swallows with redder breast plumage showed weaker tolerance (lower seasonal reproductive success) than other males. Further, we conducted experimental ectoparasite manipulations in 46 Barn Swallow nests to verify the potential effect of these parasites on the body condition of nestlings. Neither the body mass nor the hemoglobin concentration differed between the designed groups; however, the hemoglobin concentration of nestlings decreased with mite load. We concluded that the Barn Swallow population in East Asia used the tolerance strategy, rather than resistance to defend against nest mites, and the ectoparasitic mite did not appear to be a strong selective factor for reproductive success owing to the strong tolerance of the studied Barn Swallow population. [ABSTRACT FROM AUTHOR]

Background: Large yellow croaker (Larimichthys crocea) is an important commercial fish in China and East-Asia. The annual product of the species from the aqua-farming industry is about 90 thousand tons. In spite of its economic importance, genetic studies of economic traits and genomic selections of the species are hindered by the lack of genomic resources. Specifically, a whole-genome physical map of large yellow croaker is still missing. The traditional BAC-based fingerprint method is extremely time- and labour-consuming. Here we report the first genome map construction using the high-throughput whole-genome mapping technique by nanochannel arrays in BioNano Genomics Irys system. Results: For an optimal marker density of ~10 per 100 kb, the nicking endonuclease Nt.BspQ1 was chosen for the genome map generation. 645,305 DNA molecules with a total length of ~112 Gb were labelled and detected, covering more than 160X of the large yellow croaker genome. Employing IrysView package and signature patterns in raw DNA molecules, a whole-genome map of large yellow croaker was assembled into 686 maps with a total length of 727 Mb, which was consistent with the estimated genome size. The N50 length of the whole-genome map, including 126 maps, was up to 1.7 Mb. The excellent hybrid alignment with large yellow croaker draft genome validated the consensus genome map assembly and highlighted a promising application of whole-genome mapping on draft genome sequence super-scaffolding. The genome map data of large yellow croaker are accessible on lycgenomics.jmu.edu.cn/pm. Conclusion: Using the state-of-the-art whole-genome mapping technique in Irys system, the first whole-genome map for large yellow croaker has been constructed and thus highly facilitates the ongoing genomic and evolutionary studies for the species. To our knowledge, this is the first public report on genome map construction by the whole-genome mapping for aquatic-organisms. Our study demonstrates a promising application of the whole-genome mapping on genome maps construction for other non-model organisms in a fast and reliable manner. [ABSTRACT FROM AUTHOR]