Petrogenesis and tectonic setting of Mesozoic granitic rocks in Eastern South China

Triassic, Jurassic and Early Cretaceous granitoids in eastern South China were systematically sampled and their ages, geochemical compositions and zircon Hf isotopes were analysed. Six stages of Mesozoic granitoids, with different ages, textures and geochemical characteristics are identified. The granitoids were generated during an Andean-type orogenic cycle along the eastern margin of China in the Mesozoic and the properties of the granitoids were determined by their sources and temperature-pressure-water-redox conditions during melting and fractionation

A Mesozoic Andean-Type Orogenic Cycle in Southeastern China as Recorded by Granitoid Evolution

Petrology, magnetic susceptibilities, zircon U-Pb ages, zircon Hf isotopes and whole-rock geochemical data are used to constrain the evolution of Mesozoic high-potassium granitic rocks that record an Andean-type orogenic cycle in the southeastern China segment of the Western Pacific. Decreasing melting pressures of the granitic magmas from the Late Triassic to the Early Cretaceous, as reflected by decreasing Sm/Yb ratios, point to a general trend of crustal attenuation with time in western Zhejiang Province. Five distinct stages of granitic magmatism are identified: (1) 230 to 215 Ma: high-temperature, high-pressure dehydration melting in a reduced and thickened crust caused by flat-slab subduction of the paleo-Pacific Plate; (2) 170 to 150 Ma: low-temperature, high-pressure water-fluxed melting in an oxidized and thickened crust caused by the foundering of the paleo-Pacific Plate; (3) 140 to 130 Ma: low-temperature, low-pressure dehydration melting of the continental crust caused by extension of the lithosphere; (4) 130 to 125 Ma: high-temperature, low-pressure dehydration melting of the refractory materials in the continental crust caused by further extension of the lithosphere and possibly basaltic underplating; and (5) 115 to 100 Ma: emplacement of fractionation products of hydrous basalts from the enriched continental lithospheric mantle

Genomic Insights Into the Admixture History of Mongolic- and Tungusic-Speaking Populations From Southwestern East Asia

As a major part of the modern Trans-Eurasian or Altaic language family, most of the Mongolic and Tungusic languages were mainly spoken in northern China, Mongolia, and southern Siberia, but some were also found in southern China. Previous genetic surveys only focused on the dissection of genetic structure of northern Altaic-speaking populations; however, the ancestral origin and genomic diversification of Mongolic and Tungusic–speaking populations from southwestern East Asia remain poorly understood because of the paucity of high-density sampling and genome-wide data. Here, we generated genome-wide data at nearly 700,000 single-nucleotide polymorphisms (SNPs) in 26 Mongolians and 55 Manchus collected from Guizhou province in southwestern China. We applied principal component analysis (PCA), ADMIXTURE, f statistics, qpWave/qpAdm analysis, qpGraph, TreeMix, Fst, and ALDER to infer the fine-scale population genetic structure and admixture history. We found significant genetic differentiation between northern and southern Mongolic and Tungusic speakers, as one specific genetic cline of Manchu and Mongolian was identified in Guizhou province. Further results from ADMIXTURE and f statistics showed that the studied Guizhou Mongolians and Manchus had a strong genetic affinity with southern East Asians, especially for inland southern East Asians. The qpAdm-based estimates of ancestry admixture proportion demonstrated that Guizhou Mongolians and Manchus people could be modeled as the admixtures of one northern ancestry related to northern Tungusic/Mongolic speakers or Yellow River farmers and one southern ancestry associated with Austronesian, Tai-Kadai, and Austroasiatic speakers. The qpGraph-based phylogeny and neighbor-joining tree further confirmed that Guizhou Manchus and Mongolians derived approximately half of the ancestry from their northern ancestors and the other half from southern Indigenous East Asians. The estimated admixture time ranged from 600 to 1,000 years ago, which further confirmed the admixture events were mediated via the Mongolians Empire expansion during the formation of the Yuan dynasty

Identifying Complex Junctions in a Road Network

Automated generalization of road network data is of great concern to the map generalization community because of the importance of road data and the difficulty involved. Complex junctions are where roads meet and join in a complicated way and identifying them is a key issue in road network generalization. In addition to their structural complexity, complex junctions don’t have regular geometric boundary and their representation in spatial data is scale-dependent. All these together make them hard to identify. Existing methods use geometric and topological statistics to characterize and identify them, and are thus error-prone, scale-dependent and lack generality. More significantly, they cannot ensure the integrity of complex junctions. This study overcomes the obstacles by clarifying the topological boundary of a complex junction, which provides the basis for straightforward identification of them. Test results show the proposed method can find and isolate complex junctions in a road network with their integrity and is able to handle different road representations. The integral identification achieved can help to guarantee connectivity among roads when simplifying complex junctions, and greatly facilitate the geometric and semantic simplification of them

Interference-resistant heading measurement for location-based mobile services

Accurate heading information is crucial for many mobile services such as navigation, autonomous vehicles, and robot applications. The standard way to obtain heading information is by using a tri-axis magnetometer, which can measure the signal intensity of the magnetic field in three orthogonal directions. However, a magnetometer is known to be highly susceptible to environmental interferences that may easily generate error up to thousands of nano-tesla, causing unacceptable errors (e.g., 40 degrees) in the direction output and rendering the mobile service useless. We present a novel design for interference resistant heading measurement using multiple magnetometers. In this design, multiple magnetometers are placed around a circle, imitating the manual rotation of a single magnetometer. This arrangement allows us to automatically calibrate the devices against external interference, using the classic ellipse fitting method. We have implemented a system consisting of a STM32F103RC microcontroller and six AKM8975 magnetic sensors. Evaluation in realistic environments shows that our design can adaptively update the calibration parameters, reducing the original heading error from 150 degrees to below 2.5 degrees, and the heading error remains stable in environments with different patterns of magnetic perturbation

The genetic structure and admixture of Manchus and Koreans in northeast China

Background The fine-scale genetic profiles and population history of Manchus and Koreans remain unclear. Aim To infer a fine-scale genetic structure and admixture of Manchu and Korean populations. Subjects and methods We collected and genotyped 16 Manchus from Liaoning and 18 Koreans from Jilin province with about 700K genome-wide SNPs. We analysed the data using principal component analysis (PCA), ADMIXTURE, Fst, TreeMix, f-statistics, qpWave, and qpAdm. Results Manchus and Koreans showed a genetic affinity with northern East Asians. Chinese Koreans showed a long-term genetic continuity with Bronze Age populations from the West Liao River and had a strong affinity with Koreans in South Korea and Japan. Manchus had a different genetic profile compared with other Tungusic populations since the Manchus received additional genetic influence from the southern Chinese but didn’t have West Eurasian-related admixture. Conclusions The genetic formation of Manchus involving southern Chinese was consistent with the extensive interactions between Manchus and populations from central and southern China. The large-scale genetic continuity between ancient West Liao River farmers and Koreans highlighted the role farming expansion played in the peopling of the Korean Peninsula

8,9-Epoxyeicosatrienoic Acid Inhibits Antibody Production of B Lymphocytes in Mice

Epoxyeicosatrienoic acids (EETs), synthesized from arachidonic acid by cytochrome P450 epoxygenases, are converted to dihydroxyeicosatrienoic acids by soluble epoxide hydrolase. EETs exert anti-inflammatory effects. However, the effect of EETs on humoral immunity is poorly understood. The present study is to investigate the potential role of EETs on B cell function and mechanisms. We examined the role of EETs on antibody production of splenic B cells from C57BL/6 and apolipoprotein E-deficient (ApoE−/−) mice by means of ELISA. Of the 4 EET regioisomers, 8,9-EET decreased basal and activation-induced B cell antibody secretion. As well, 8,9-EET significantly inhibited B-cell proliferation and survival, plasma cell differentiation and class-switch recombination. Western blot analysis revealed that lipopolysaccharide-induced nuclear translocation of NF-κB could be attenuated by 8,9-EET. Furthermore, germinal center formation was impaired by 8,9-EET in mice in vivo. 8,9-EET may inhibit B-cell function in vitro and in vivo, which suggests a new therapeutic strategy for diseases with excess B cell activation

Protocol for a comprehensive pipeline to study ancient human genomes

Summary: Ancient genomics has revolutionized our understanding of human evolution and migration history in recent years. Here, we present a protocol to prepare samples for ancient genomics research. We describe steps for releasing DNA from human remains, DNA library construction, hybridization capture, quantification, and sequencing. We then detail procedures for mapping sequence reads and population genetics analysis. This protocol also outlines challenges in extracting ancient DNA samples and authenticating ancient DNA to uncover the genetic history and diversity of ancient populations.For complete details on the use and execution of this protocol, please refer to Tao et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics

Illite K-Ar Dating of the Leibo Fault Zone, Southeastern Margin of the Tibetan Plateau:Implications for the Quasi-Synchronous Far-Field Tectonic Response to the India-Asia Collision

Whether tectonic strain from the early stage India-Asia collision has synchronously affected the far-field margin of the Tibetan Plateau is crucial for understanding plateau deformation and growth processes. However, direct evidence for early far-field deformation remains scarce. Utilizing illite K-Ar dating of three fault gouge samples, we established the faulting history of the Leibo fault zone (LFZ) at the southeastern margin of the Tibetan Plateau (SEMTP). Consistent authigenic illite ages of 52 ± 2, 54 ± 12 and 55 ± 6 Ma suggest the reactivated thrust faulting of the LFZ in the Early Cenozoic. Positioned ∼700 km east of the collisional boundary and at the intersection of three blocks with distinct lithospheric rheology in strength/viscosity, this event suggests a quasi-synchronous far-field tectonic response in the SEMTP to the India-Asia collision.</p

8,9-EET inhibited plasma-cell differentiation of B cells.

<p>A. Splenic B cells were stimulated with 5 µg/ml LPS and 50 ng/ml IL-4 with or without 8,9-EET (1 µM) for 3 days, then CD138 expression was analyzed by flow cytometry. B. Quantification of 3 independent experiments of plasma cell differentiation. Quantification of real time PCR and western blot analysis of mRNA (C) and protein (D) expressions of IRF-4 and XBP-1 in B cells cultured with 8,9-EET, 5 µg/ml LPS and 50 ng/ml IL-4 for 3 days. GAPDH was used as the control. Data are means ± SEM of three independent experiments. *, <i>P</i><0.05 vs. no 8,9-EET.</p