Search

Simple Summary: Haemaphysalis longicornis is a predominant tick species in East Asia and infests humans, cattle and wildlife. It is also a common vector for pathogen transmission. The microbial community in tick midguts not only affects the transmission of tick-borne pathogens but also indirectly affects the development, metabolism, reproduction, and other physiology of ticks. There have been rare reports on the effects of different types of hosts on the microbial composition of tick midguts. Here, we conducted a midgut microbiome of H. longicornis collected from tiger and deer by high-throughput sequencing and showed that the relative abundance of each bacterium varied greatly at different classification levels. Haemaphysalis longicornis is a common tick species that carries several pathogens. There are few reports on the influence of different hosts on the structure of midgut microflora in H. longicornis. In this study, midgut contents of fully engorged female H. longicornis were collected from the surface of tiger (Panthera tigris) and deer (Dama dama). The bacterial genomic DNA of each sample was extracted, and the V3–V4 regions of the bacterial 16S rRNA were sequenced using the Illumina NovaSeq sequencing. The diversity of the bacterial community of the fully engorged female H. longicornis on the surface of tiger was higher than that of deer. In total, 8 phyla and 73 genera of bacteria annotations were detected in the two groups. At the phylum level, the bacterial phyla common to the two groups were Proteobacteria, Firmicutes, and Actinobacteriota. At the genus level, there were 20 common bacterial genera, among which the relative abundances of Coxiella, Morganella, Diplorickettsia, and Acinetobacter were high. The Morganella species was further identified to be Morganella morganii. The alpha diversity index indicated that the bacterial diversity of the tiger group was higher than that of the deer group. Bacteroidota, Patescibacteria, Desulfobacterota, Verrucomicrobiota, and Cyanobacteria were solely detected in the tiger group. A total of 52 bacterial genera were unique in the tiger group, while one bacterial genus was unique in the deer group. This study indicates that there are differences in the structure of the gut bacteria of the same tick species among different hosts. Further culture-based methods are needed to provide a more comprehensive understanding of the tick microbiota parasitizing different hosts. [ABSTRACT FROM AUTHOR]

Long-range transport of anthropogenic air pollutants from East Asia can affect the downwind marine air quality during spring and winter. Long-range transport of continental air pollutants and their interaction with sea salt aerosol (SSA) significantly modify the radiative forcing of marine aerosols and influence ocean biogeochemical cycling. Previous studies poorly characterize variations of aerosol particles along with air mass transport from the continental edge to the remote ocean. Here, the research ship R/V Dongfanghong 2 traveled from the eastern China seas (ECS) to the northwestern Pacific Ocean (NWPO) to understand what and how air pollutants were transported from the highly polluted continental air to clean marine air in spring. A transmission electron microscope (TEM) was used to find the long-range transported anthropogenic particles and the possible Cl-depletion phenomenon of SSA in marine air. Anthropogenic aerosols (e.g., sulfur (S)-rich, S-soot, S-metal/fly ash, organic matter (OM)-S, and OM coating particles) were identified and dramatically declined from 87 % to 8 % by number from the ECS to remote NWPO. For the SSA aging, 87 % of SSA particles in the ECS were identified as fully aged, while the proportion of fully aged SSA particles in the NWPO decreased to 29 %. Our results highlight that anthropogenic acidic gases in the troposphere (e.g., SO 2 , NO x , and volatile organic compounds) could be transported to remote marine air and exert a significant impact on aging of SSA particles in the NWPO. The study shows that anthropogenic particles and gases from East Asia significantly perturb different aerosol chemistry from coastal to remote marine air. More attention should be given to the modification of SSA particles in remote marine areas due to the influence of anthropogenic gaseous pollutants. [ABSTRACT FROM AUTHOR]

The western Ordos Basin is located at the intersection of multiple tectonic units and is a key area in the restoration of the palaeogeographic pattern of the East Asia region. The stability of the area and well-developed Paleozoic strata in the basin provide ideal conditions for revealing the relationships among the tectonic processes apparent there. However, within the constraints of extensive post-depositional modification, poor-quality seismic data, and a lack of wells, sediment dispersion differences, source attribution, and source-to-sink processes are still unclear. In this study, we integrated sedimentology, mineral, and geochemical data obtained from marine, continental, and marine-continental transition sedimentary environments in the study area in order to reveal the evolution from source-to-sink. The results show that the western Ordos Basin was predominantly supplied by the Alxa block, Yinshan orogenic belt, Qilian orogenic belt, and the North Qinling orogenic belt during the Late Paleozoic era. As a result of the closure of the Paleo Asian Ocean, the Alxa block and Yinshan orogenic belt became the primary source areas to the north, being composed of granite and alkaline basalt and some sedimentary rocks. In the southern area, the Qilian and the Northern Qinling orogenic belts were subjected to the PaleoTethys remnant ocean basin subduction during the Early Permian. Granite and alkaline basalt were the source rocks of the North Qinling orogenic belt, which became the source area during the Shanxi period. The Qilian orogenic belt contains some sedimentary rocks. The continuous uplift of the southern and northern orogenic belts. The tectonic setting of the northern source area transitions from a passive continental margin to an active continental margin with a mixture of continental arc. The tectonic setting of the southern source area transitions from a mixture of passive continental margin and active continental margin to an active continental margin and continental island arc. The climate changes gradually from humid to semi-arid and then to arid, and meanwhile, the sea level shows a decreasing trend, leading to an increasing distance of advancement for each source-to-sink system, and gradually converged in the central and eastern regions of the basin. Tidal and fan delta sandy sediments in the study area were transformed into fluvial delta sandy sediments in the northern two source-to-sink systems. The southern source-to-sink systems gradually changed from scattered sandbarrier and coastal sandy sediment to fluvial sandy sediment after the Shanxi Formation. • No apparent source from the North Qinling Belt before Shanxi Formation. • Subduction/collision time difference between Ocean Basins create a north-south difference in dispersal of sandy sediments. • Sandy sediments dispersal in marine-continental transition influenced by climate, sea-level, and basin accommodation space. [ABSTRACT FROM AUTHOR]

We sequenced and annotated the complete mitochondrial genome (mitogenome) of Bactrocera scutellata (Diptera: Tephritidae), which is an economically important pest in many area of East Asia. This mitogenome is 15,850 bp in length with an A + T content of 72.99%, and contains 37 typical animal mitochondrial genes that are arranged in the same order as that of the inferred ancestral insects. All protein-coding genes (PCGs) start with a typical ATN codon, with the exception of cox1, which begins with TCG. Ten PCGs stop with termination codon TAA or TAG, whereas cox1, nad1 and nad5 have single T as the incomplete stop codon. All of the transfer RNA genes present the typical clover leaf secondary structure excepting trnS1 (AGN) without a DHU-arm. The A + T-rich region (945 bp in length with 84.66% A + T content) is located between rrnS and trnI, and contains a 20 bp poly-T stretch and 21 bp poly-A stretch. Excepting the control region, the longest intergenic spacer locates between trnR and trnN which is 56 bp long with an excessive high A + T content (89.29%). Compared with other two mitogenomes of B. scutellata revealed that the mutation rates of mitochondrial genes were quite different. For population genetic studies of this species, we recommend using the cox1 or nad5 genes. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the effect of four common variants (rs2237892, rs2283228, rs2237895, and rs2237897) in KCNQ1 on susceptibility of type 2 diabetes (T2D) by performing a case-control study as well as a comprehensive meta-analysis. We genotyped these four variants in two sets of Chinese Han population, comprising a total of 2533 type 2 diabetic patients and 2643 nondiabetic controls. We also performed a meta-analysis of our results with published studies in East Asians, meanwhile assessing the population attributable risk (PAR) of these variants. By combining our case-control sets, a total of 45,204 T2D cases and 42,832 controls were included in the meta-analyses. The per-allele ORs ranged from 1.24 to 1.33, and the PARs ranged from 15.8% to 31.8%, with SNP rs2237892 being the most widely studied (16 articles containing a total of 38,338 cases and 35,907 controls), showing strongest association (per-allele OR: 1.33, 95% CI: 1.28-1.39) and indicating the highest PAR (31.8%). This study confirmed the strong association between common variants in KCNQ1 and risk of T2D. Variants in KCNQ1 were among the leading genetic factors contributing to the overall burden of T2D in East Asians. [ABSTRACT FROM AUTHOR]

Atmospheric nitrogen (N) deposition is a vital component of the global N cycle. Excessive N deposition on the Earth's surface has adverse impacts on ecosystems and humans. Quantification of atmospheric N deposition is indispensable for assessing and addressing N deposition-induced environmental issues. In the present review, we firstly summarized the current methods applied to quantify N deposition (wet, dry, and total N deposition), their advantages and major limitations. Secondly, we illustrated the long-term N deposition monitoring networks worldwide and the results attained via such long-term monitoring. Results show that China faces heavier N deposition than the United States, European countries, and other countries in East Asia. Next, we proposed a framework for estimating the atmospheric wet and dry N deposition using a combined method of surface monitoring, modeling, and satellite remote sensing. Finally, we put forth the critical research challenges and future directions of the atmospheric N deposition. A review of quantification methods and the global data on nitrogen deposition and a systematic framework was proposed for quantifying nitrogen deposition. [Display omitted] • Inferential method is widely used by the global monitoring networks to quantify dry deposition. • Wet-only sampling and bulk collector are widely used to quantify wet/bulk deposition. • A framework containing monitoring, modeling, and satellite methods was proposed. • China is subjected to the highest nitrogen deposition worldwide. [ABSTRACT FROM AUTHOR]

Recently, NASA has released the newest Moderate Resolution Imaging Spectroradiometer (MODIS)/Terra Collection 6.1 (C6.1) aerosol product generated at a higher spatial resolution of 3 km (i.e., MOD04_3K) with main updates in the radiation calibration and the Dark Target (DT) aerosol algorithm. This product is of great importance for air pollution studies at small to medium scales but has not been fully evaluated. This paper aims to provide a comprehensive validation and error analysis of the MOD04_3K C6.1 aerosol optical depth (AOD) data set against Aerosol Robotic Network (AERONET) Version 3 AOD measurements at different spatiotemporal scales from 2013 to 2017 over land and ocean. Results suggest that the data quality of the MOD04_3K AOD data set is overall improved at different spatial scales after quality control. In general, the highest-quality 3 km AOD retrievals (quality assurance = 3) and ground-based measurements are highly correlated (correlation coefficient = 0.81), with a mean absolute error of 0.08 and a root-mean-square error of 0.12. About 63% of the data samples fall within the expected error envelope on a global scale. Nevertheless, there is large spatial heterogeneity in the performance at regional and site scales, with the worse accuracy generally observed in areas covered by bright surfaces or dominated by human activities. This is mainly due to the difficulties in estimating surface reflectance and the aerosol-type assumption. In addition, aerosol retrievals are overall overestimated, especially over North America, Europe, and East Asia. Furthermore, the estimation errors and uncertainties are highly related to varying surface and atmospheric aerosol conditions, which become larger with increases in surface brightness, aerosol loading, Ångström exponent and single scattering albedo. The MODIS 3 km AOD data set is generally less accurate than its coarser-spatial-resolution (10 km) counterpart due to a decrease in the opportunity to discard marginal pixels from the retrieval. Therefore, further algorithm improvements are needed to reduce the estimation uncertainty, especially for heterogeneous urban and bright surfaces. • MODIS Collection 6.1 3 km resolution AOD products are evaluated globally. • The accuracy has been improved overall after data quality control. • Retrievals errors related to varying surface and atmospheric conditions are analyzed. • MODIS 3 km DT AOD product is generally less accurate than the 10 km DT release. [ABSTRACT FROM AUTHOR]