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Background: Understanding the relationship between human evolution and environmental changes is the key to lifting the veil on human origin. The hypothesis that environmental changes triggered the divergence of humans from apes (ca. 9.3–6.5 million years ago, Ma) has been poorly tested because of limited continuous environmental data from fossil localities. Lufengpithecus (12.5-6.0 Ma) found on the southeastern margin of the Tibetan Plateau (SEMTP) across the ape–human split provides a good chance for testing this hypothesis. Results: Here, we reconstructed the habitats of L. keiyuanensis (12.5–11.6 Ma) with comprehensive vegetation, climate, and potential food web data by palaeobotanical evidence, together with other multidisciplinary data and partly tested the environment-driven hypothesis by revealing the living conditions of Lufengpithecus. Conclusion: A detailed comparison of hominoids on different continents reveals their behaviour and fate divergence across the ape–human split against the background of global climate change, i.e., the stable living conditions of SEMTP not only provided a so-called 'refuge' for arboreal Lufengpithecus but also acted as a 'double-edged sword', preventing their further evolution while vegetation shifts in East Africa probably stimulated the emergence of human bipedalism, and the intense climatic changes in Europe possibly prevented those hominoids from surviving that time interval. Our findings provide interesting insight into the environmental impacts on the behavioural evolution of hominoids. [ABSTRACT FROM AUTHOR]

The bean bug Riptortus pedestris is a notorious insect pest that can damage various crops, especially soybean, in East Asia. In insects, the olfactory system plays a crucial role in host finding and feeding behaviour in which the odorant‐binding proteins (OBPs) are believed to be involved in initial step in this system. In this study, we produced the R. pedestris adult antennae‐expressed RpedOBP4 protein using a recombinant expression system in E. coli. Fluorescence competitive binding confirmed that RpedOBP4 has binding affinities to 7 of 20 soybean volatiles (ligands), and that a neutral condition is the best environment for it. The binding property of RpedOBP4 to these ligands was further revealed by integrating data from molecular docking, site‐directed mutagenesis and ligand binding assays. This demonstrated that five amino acid residues (I30, L33, Y47, I57 and Y121) are involved in the binding process of RpedOBP4 to corresponding ligands. These findings will not only help us to more thoroughly explore the olfactory mechanism of R. pedestris during feeding on soybean, but also lead to the identification of key candidate targets for developing environmental and efficient behaviour inhibitors to prevent population expansion of R. pedestris in the future. [ABSTRACT FROM AUTHOR]

Riptortus pedestris is one of the most destructive pests of leguminous crops in East Asia. In this study, we assessed the effect of different leguminous plant species, including soybean, wild soybean, white kidney bean, runner bean, pea, cowpea, adzuki bean, mung bean, faba bean, and lentil vetch, on the development and reproduction of R. pedestris. We found that leguminous plant species significantly affect the developmental duration and survivability of the nymphs, adult longevity, and oviposition and fecundity in R. pedestris. The nymphs completed their development on all of these plants. The developmental duration of nymphs was the shortest (16.24 ± 0.57 days) on soybean and the longest (31.33 ± 1.76 days) on faba bean. The rates of survival of nymphs on soybean and pea were 93.2% and 93.0%, respectively. Female adults survived the longest on soybean (64.67 ± 6.64 days) and the shortest (13.27 ± 3.67 days) on white kidney bean. The fecundity on faba bean (decorticated pods) (143.0 ± 28.04 eggs) and soybean (116.63 ± 12.76 eggs) was higher than those on other plants. The age‐specific life table revealed that the population trend index values were all >1 except on wild soybean and faba bean, and the highest was on soybean (30.36), followed by pea (21.0). Soybean and pea were identified as the most suitable hosts for R. pedestris because of their shorter developmental duration, higher survivability, longevity and fecundity and greater population trend index on these hosts, while wild soybean and faba bean were relatively unsuitable host plants. [ABSTRACT FROM AUTHOR]

We initiate the Westlake BioBank for Chinese (WBBC) pilot project with 4,535 whole-genome sequencing (WGS) individuals and 5,841 high-density genotyping individuals, and identify 81.5 million SNPs and INDELs, of which 38.5% are absent in dbSNP Build 151. We provide a population-specific reference panel and an online imputation server (https://wbbc.westlake.edu.cn/) which could yield substantial improvement of imputation performance in Chinese population, especially for low-frequency and rare variants. By analyzing the singleton density of the WGS data, we find selection signatures in SNX29, DNAH1 and WDR1 genes, and the derived alleles of the alcohol metabolism genes (ADH1A and ADH1B) emerge around 7,000 years ago and tend to be more common from 4,000 years ago in East Asia. Genetic evidence supports the corresponding geographical boundaries of the Qinling-Huaihe Line and Nanling Mountains, which separate the Han Chinese into subgroups, and we reveal that North Han was more homogeneous than South Han. Biobanks of genetic data have been primarily in European populations, which gives us an incomplete understanding of complex traits across populations. Here, the authors initiate the Westlake BioBank for Chinese (WBBC) pilot project with 4,535 whole genome sequences and 5,841 high-density genotypes from China, characterizing large-scale genomic variation in Chinese populations. [ABSTRACT FROM AUTHOR]

To investigate the characteristics of atmospheric brown carbon (BrC) in the semiarid region of East Asia, PM 2.5 and size-resolved particles in the urban atmosphere of Xi'an, inland China, during the winter and summer of 2017 were collected and analyzed for optical properties and chemical compositions. Methanol extracts (MeOH extracts) were more light-absorbing than water extracts (H2O extracts) in the optical wavelength of 300–600 nm and well correlated with nitrophenols, polycyclic aromatic hydrocarbons (PAHs) and oxygenated PAHs (r>0.78). The light absorptions (abs λ=365nm) of H2O extracts and MeOH extracts in winter were 28±16 and 49±32 M m -1 , respectively, which are about 10 times higher than those in summer, mainly due to the enhanced emissions from biomass burning for house heating. Water-extracted BrC predominately occurred in the fine mode (< 2.1 µ m) during winter and summer, accounting for 81 % and 65 % of the total absorption of BrC, respectively. The light absorption and stable carbon isotope composition measurements showed an increasing ratio of abs λ=365nm -MeOH to abs λ=550nm -EC along with an enrichment of 13C in PM 2.5 during the haze development, indicating an accumulation of secondarily formed BrC (e.g., nitrophenols) in the aerosol aging process. Positive matrix factorization (PMF) analysis showed that biomass burning, fossil fuel combustion, secondary formation, and fugitive dust are the major sources of BrC in the city, accounting for 55 %, 19 %, 16 %, and 10 % of the total BrC of PM 2.5 , respectively. [ABSTRACT FROM AUTHOR]

The regional distribution of an ancient Y-chromosome haplogroup C-M130 (Hg C) in Asia provides an ideal tool of dissecting prehistoric migration events. We identified 465 Hg C individuals out of 4284 males from 140 East and Southeast Asian populations. We genotyped these Hg C individuals using 12 Y-chromosome biallelic markers and 8 commonly used Y-short tandem repeats (Y-STRs), and performed phylogeographic analysis in combination with the published data. The results show that most of the Hg C subhaplogroups have distinct geographical distribution and have undergone long-time isolation, although Hg C individuals are distributed widely across Eurasia. Furthermore, a general south-to-north and east-to-west cline of Y-STR diversity is observed with the highest diversity in Southeast Asia. The phylogeographic distribution pattern of Hg C supports a single coastal ‘Out-of-Africa’ route by way of the Indian subcontinent, which eventually led to the early settlement of modern humans in mainland Southeast Asia. The northward expansion of Hg C in East Asia started ∼40 thousand of years ago (KYA) along the coastline of mainland China and reached Siberia ∼15 KYA and finally made its way to the Americas. [ABSTRACT FROM AUTHOR]

Background: At the southern entrance to East Asia, early population migration has affected most of the Y-chromosome variations of East Asians. Methodology/Principal Findings: To assess the isolated genetic structure of Hainan Island and the original genetic structure at the southern entrance, we studied the Y chromosome diversity of 405 Hainan Island aborigines from all the six populations, who have little influence of the recent mainland population relocations and admixtures. Here we report that haplogroups O1a* and O2a* are dominant among Hainan aborigines. In addition, the frequency of the mainland dominant haplogroup O3 is quite low among these aborigines, indicating that they have lived rather isolated. Clustering analyses suggests that the Hainan aborigines have been segregated since about 20 thousand years ago, after two dominant haplogroups entered East Asia (31 to 36 thousand years ago). Conclusions/Significance: Our results suggest that Hainan aborigines have been isolated at the entrance to East Asia for about 20 thousand years, whose distinctive genetic characteristics could be used as important controls in many population genetic studies. [ABSTRACT FROM AUTHOR]

Examines the protective effect of chemokine receptor CCR2-64I against AIDS in East Asia. Observation of decreasing cline of CCR2-64I frequency; Involvement of CCR2 and stromal-derived factor in HIV infection and AIDS symptom onset; Evaluation of risk of AIDS onset based on genotypes.

Y-chromosome Haplogroup O is the dominant lineage of East Asians, comprising more than a quarter of all males on the world; however, its internal phylogeny remains insufficiently investigated. In this study, we determined the phylogenetic position of recently defined markers (L127, KL1, KL2, P164, and PK4) in the background of Haplogroup O. In the revised tree, subgroup O3a-M324 is divided into two main subclades, O3a1-L127 and O3a2-P201, covering about 20 and 35% of Han Chinese people, respectively. The marker P164 is corrected from a downstream site of M7 to upstream of M134 and parallel to M7 and M159. The marker PK4 is also relocated from downstream of M88 to upstream of M95, separating the former O2* into two parts. This revision evidently improved the resolving power of Y-chromosome phylogeny in East Asia. [ABSTRACT FROM AUTHOR]

In epidemiological studies, it is easier to glean information from isolated populations with simple genetic backgrounds than from populations with relatively complex genetic backgrounds. Regarded as an isolated population, the Minz (Hei-Yi Zhuang) in Napo County (in the China-Vietnam borderland) has been the subject of numerous recent studies. To assess the genetic isolation of this population, we studied Y chromosome and mitochondrial DNA from Minz and Han in Napo. Both populations exhibited southern Chinese genetic characteristics in both paternal and maternal lineages. Using NETWORK analyses, we found pronounced gene flow between these two populations only in maternal lineages. We also observed gene flow from other populations into the Minz gene pool. We thus concluded that the Minz is not a genetically isolated population and it is increasingly difficult to find isolated populations in mainland East Asia. [ABSTRACT FROM AUTHOR]

This study reveals the impact of biomass burning (BB) on secondary organic aerosols (SOA) formation in the North China Plain (NCP). Filter samples were analyzed for secondary inorganic aerosols (SIA), oxalic acid (C 2) and related aqueous-phase SOA compounds (aqSOA), stable carbon isotope composition of C 2 (δ13C(C 2)) and aerosol liquid water content (ALWC). Based on the PM 2.5 loadings, BB tracer concentrations, wildfire spots and air-mass back trajectories, we distinguished two episodes from the whole campaign, Episode I and Episode II, which were characteristic of regional and local BB, respectively. The abundances of PM 2.5 and organic matter in the two events were comparable, but concentrations and fractions of SIA, aqSOA during Episode I were much higher than those during Episode II, along with heavier δ13C(C 2), suggesting an enhanced aqSOA formation in the earlier period. We found that the enhancement of aqSOA formation during Episode I was caused by an increased ALWC, which was mainly driven by SIA during the regional BB event. Our work showed that intensive burning of crop residue in East Asia can sharply enhance aqSOA production on a large scale, which may have a significant impact on the regional climate and human health. Image 1 • Intensive regional biomass burning could lead to high aerosol liquid water content. • Aqueous-phase secondary organic aerosols was enhanced by aerosol liquid water. • Positive feedback loop between secondary inorganic, organic aerosols and aerosol water. • Regional biomass burning had heavier oxalic acid stable isotopes than locally. Our study shows that aqueous-phase SOA (aqSOA) were largely enhanced by the aerosol liquid water content (ALWC), which was mainly driven by secondary inorganic aerosols during the intensive regional biomass burning of the crop residues. [ABSTRACT FROM AUTHOR]

The prehistoric peopling of East Asia by modern humans remains controversial with respect to early population migrations. Here, we present a systematic sampling and genetic screening of an East Asian-specific Y-chromosome haplogroup (O3-M122) in 2,332 individuals from diverse East Asian populations. Our results indicate that the O3-M122 lineage is dominant in East Asian populations, with an average frequency of 44.3%. The microsatellite data show that the O3-M122 haplotypes in southern East Asia are more diverse than those in northern East Asia, suggesting a southern origin of the O3-M122 mutation. It was estimated that the early northward migration of the O3-M122 lineages in East Asia occurred ∼25,000–30,000 years ago, consistent with the fossil records of modern humans in East Asia. [ABSTRACT FROM AUTHOR]