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Crystal-size and spatial distributions of minerals in metamorphic rocks provide insight into their nucleation, growth environment, and the metamorphic evolution of their host rocks. Episodic nucleation and growth histories for garnets in eclogites from the DaNe orogen are revealed by variations in crystal size, geochemical zoning, and mineralogy of inclusions in garnets. The studied garnets show pseudo-lognormal crystal-size distributions (CSDs), prograde chemical zoning patterns indexed by mineral inclusions, and are mainly distributed at random. Constant growth rate for each episode is proposed based on the mineralogy of inclusions in garnets and the chemical zoning patterns. The CSD shapes were evaluated in terms of a size-dependent proportionate growth model and a thermally accelerated, diffusion-controlled model but neither is consistent with the geochemical data and the concordant occurrence of mineral inclusions in garnet. Initial increasing nucleation rate followed by a subsequent, medial stage of nearly constant growth and finally declining nucleation rate is inferred from the CSD data. This study suggests that linking chemical analysis with textural analysis is crucial to avoid misleading interpretation solely through CSD shapes of minerals in metamorphic rocks. Keywords: Garnet, crystal size, zoning, growth, DaNe

Detailed electron- and ion-microprobe analyses were carried out on atoll-shaped and normal garnets in ultrahigh-pressure (UHP) metamorphic eclogite from Dabie, east-central China. Compositional profiles of both normal garnets and rings of atoll garnets show well-preserved growth zoning with a decrease in Mn, Ca, and heavy rare earth elements (HREEs), and an increase in Mg toward rims. Manganese and middle rare earth element (MREE) enrichments are observed near garnet rims. Island- and peninsula-shaped garnet inside atolls are homogeneous in major elements and show the same composition as garnet rims, whereas the HREE concentrations are similar to those of the normal garnet cores. Electron back-scatter diffraction (EBSD) analyses show that the island- and peninsula-shaped garnet fractions inside atolls have crystallographic orientations identical to that of the atoll rings. These observations suggest that the atoll garnets were formed by the consumption of earlier-formed cores by fluid released from both hydroxyl exsolution from the nominally anhydrous minerals (NAMs) and lawsonite decomposition at the onset of exhumation, (i.e., garnet breakdown was from the inside and re-growth from outside to inside). Though somewhat restricted, this study reveals that because garnet and zircon act as sinks for HREEs and Zr, respectively, the majority of released HREEs and Zr were likely re-incorporated into newly grown garnet and zircon during the Dabie UHP metamorphic slab exhumation. Keywords: Atoll garnet, fluid, eclogite, Dabie

The post-orogenic evolution of the Dabie Shan in eastern China is examined. Results and interpretations of the low-temperature post-orogenic history of Dabie Shan are also presented using apatite and zircon (U-Th)/He (AHe and ZHe) and apatite fission-track (AFT) thermochronometry.

Drilling has revealed suites of magnesian granite and diorite emplaced in Early Jurassic time (198-195 Ma) and an arc-related low-temperature (678 to 696°C) magmatism in NE South China Sea. These rocks have 87Sr/86Sri (0.705494 to 0.706623) and εNdt (−0.9 to +2.2) as evidence of evolved mantle-derived magmas, coupled with enriched fluid-mobile elements Cs to K and Pb implying involvement of subduction-zone fluids. Another Early Jurassic granodiorite (zircon U-Pb 187 Ma) drilled from the SW East China Sea, a magnesian high-K calc alkaline, is comparably confined to a range of low-temperature (~675°C) arc-related granite, characterized by enrichment of fluid-mobile elements and Nb-Ta depletion. Its Sr-Nd isotopes (87Sr/86Sri = 0.705200, εNdt = 1.1) suggest a product of evolved mantle-derived melts. Together with detrital igneous zircons from Paleocene sequences, these observations reveal an Early Jurassic arc-related low-temperature (600 to 740°C) magmatism in the SW East China Sea. These arc-related granitoids, along with those from SE Taiwan, could define an Early Jurassic NE-SW trending Dongsha-Talun-Yandang magmatic arc zone along the East Asian continental margin paired with Jurassic accretionary complexes from SW Japan, East Taiwan to the West Philippines. This arc-subduction complex assembly was associated with oblique subduction of the paleo-Pacific slab beneath Eurasia, presumably responsible for Early Jurassic lithospheric extension in south China block. [ABSTRACT FROM AUTHOR]

The granitoid suites encountered by drilling in the northern South China Sea (SCS) remain important for understanding the evolution of the late Mesozoic Southeast Asian continental margin. They comprise a range of rock types including diorite, tonalite, granodiorite, monzogranite and syenogranite with SiO2spanning 56.4–76.8%. Newly acquired secondary ion mass spectrometry (SIMS) U–Pb ages of samples from 14 boreholes indicate two key magmatic episodes: Late Jurassic (161.6–148.2 Ma) and Early Cretaceous (136.5–101.7 Ma). Jurassic magmatism probably began in late Middle Jurassic time, documented by the dates of inherited zircons. The granitoids are dominated by metaluminous to weakly peraluminous I-type granites, are transitional between magnesian and ferroan, and encompass calc-alkaline, high-K calc-alkaline, and shoshonitic series. The geochemical signatures suggest that these granitoids were mostly generated in a normal continental arc environment. Notable features of the I-type samples are well-defined negative Nb–Ta–Ti anomalies typical of arc-related magmas. Taken together, the late Mesozoic arc granites of the SCS, the accretionary wedge of the Palawan terrane to the southeast, and the zone of lithospheric extension north of the SCS throughout Southeast China, define a southeast-to-northwest trench-arc-backarc architecture for the late Mesozoic Southeast Asian continental margin whose geodynamic setting is related to subduction of the Palaeo-Pacific slab beneath the Asian continent. Two key subduction episodes are recognized, one in Late Jurassic and the other in Early Cretaceous time. [ABSTRACT FROM PUBLISHER]

Abstract: Having a maximum depositional depth up to 15 km, the NE-trending Xihu Depression is evolved from a deep Paleogene continental margin rifting along the present-day East China Sea continental shelf. In this paper we use deep seismic reflection, well logging, and gravity data to synthesize early rifting process of the depression. To study the regional tectonic subsidence history we developed a computer program that performs backstripping and simultaneous inversion for stretching factor, initial lithospheric thickness and incipient age of thermal subsidence. Tectonic subsidence analyses of 40 industrial wells reveal nonuniform stretching — preferential crustal extension along the depocenter but preferential mantle extension at the western flank. Uniform extension may have occurred only somewhere between the central inversion zone and the western margin. In the early rifting stage, subdued initial subsidence or initial uplift is observed on several wells near the western margin, due possibly to flexural isostatic balance. The initial mechanical lithospheric thicknesses from subsidence inversion seem to vary from about 55 km to almost 130 km, suggesting significant longitudinal segmentation as well as transverse variation in the prerifting lithosphere. It is likely that the southern part of the Xihu Depression was developed initially on a region of relatively thin lithosphere, a statement conformable to geological evidences. NW–SE trending deep seismic profiling clearly reveals the deep basement structure of the depression, as well as the synrift and postrift sedimentary packages separated by a breakup unconformity. Crustal layer thicknesses are independently estimated from gravity modeling/inversion, tectonic subsidence analyses, and deep seismic profiling, respectively. These methods all arrive at very small present-day thicknesses of the crustal layer beneath the depocenter of the Xihu Depression. [Copyright &y& Elsevier]

Examines apatite and zircon samples from a near vertical section in the Tiantangzhai region at the core of the Dabieshan orogen in China. Integrated fission track analysis; Cooling/exhumation of the region during the Late Cretaceous and Early Tertiary period; Age-elevation relationships for different dating system.

Presents methodology of zircon (uranium-thorium)/helium analysis of thermochronological constraints on Cretaceous thermal extension of Dabieshan orogeny. Evidence that the Yuexi-Luotian core was a thermal dome in Cretaceous; Distribution of Cretaceous granitoids; Magnitude of exhumation in the core.

With the development of next-generation sequencing methods, dysbiosis patterns of the vaginal microbiome have been described worldwide, but the correlation between dysbiosis and clinical symptoms, which is crucial for understanding the vaginal microbiome-host interaction, is largely unknown. The present study identified 4 types of community states in 88 women with vaginal dysbiosis. These community state types (CSTs) were dominated by non- iners Lactobacillus (CST1), L.iners (CST2) , and Gardnerella vaginalis (CST3) , and a variety of dominant species other than the above three (CST4). We found that urodynia or lumbodynia was more prevalent in women with CST4 than in women with CST3, and cervical hypertrophy was more prevalent in women with CST4 than in women with CST2 and CST3. These results indicate that patients in CST4 may have a greater tendency of vaginal symptoms, and the detailed mechanisms underlying these correlations of specific microbes with host symptoms should be further studied. • Gardnerella vaginalis dominant vaginal dysbiosis was not the most prevalent type in women with vaginal symptoms. • Vaginal dysbiosis dominated with miscellaneous bacteria correlated with severer clinical symptoms. • Some vaginal bacteria which did not receive much attention correlated with the appearance of some vaginal symptoms. [ABSTRACT FROM AUTHOR]

Abstract: In an effort to further advance our understanding of the evolution of the Sulu–Dabie orogen and its complex interactions with the Tanlu fault, and to tackle non-unique geophysical interpretations, we characterize the 3D geological structures and dynamics of the Sulu–Dabie orogen and its environs using various data processing and interpretation of a very large suite of gravimetric, magnetic, magnetotelluric, geothermal, and seismic data. We have modeled regional geothermal field of the lithosphere by incorporating both surface heat flow and Curie-point depths inverted from magnetic anomalies. This gives better constraints on regional thermal lithospheric thicknesses, which are found to be small (mostly between 55 and 95km), conformable to other geophysical results, and supportive of lithospheric de-rooting. From regional geotherms and Bouguer gravity anomalies, we assess depths, temperatures and heat flow of the Moho, and find that mantle contributes a little over 70% of the total surface heat flow. Large differences in thermal lithospheric thicknesses and geothermal activities are found between the Sulu and the Dabie segments of the Sulu–Dabie orogen. These differences result, at least partially, from large vertical differential movement at the lithospheric scale across the Tanlu fault, as seen from both reflection seismic sections and gravity anomalies. Within the Sulu–Dabie orogenic belt, reduction to the pole and 3D analytic signal analysis on magnetic anomalies reveal that positive magnetic anomalies associated with this belt are most due to gneiss, migmatite and Mesozoic granites, whereas ultrahigh-pressure metamorphic zones show weak or negative magnetic anomalies. This interesting magnetic contrast between ultrahigh-pressure metamorphic rocks and surrounding rocks suggests that ultrahigh-pressure metamorphic minerals are either only weakly magnetized, or possibly retrograded and remagnetized over a long time span or in a period of reversed magnetization. High-pressure metamorphic minerals of blueschist facies appear to be less susceptive than ultrahigh-pressure metamorphic minerals. [Copyright &y& Elsevier]

• Zircon fission track analyses of the pre-Cretaceous sandstones are reported. • ZFT data constrain the low-temperature evolution or sediment provenance. • The westward decreasing trend in age represents a Mesozoic intracontinental orogeny. • Sediments source from the Qinling orogen due to its multistage evolution. The Xuefeng Intracontinental Tectonic System (XITS) is a large-scale compressional tectonic system in the central South China block. It is characterized by northeast-trending fold-thrust belts involving the Xuefeng zone, the Chevron syncline fold-thrust zone, the Chevron anticline fold-thrust zone and the Central Sichuan basin. This paper reports detrital zircon fission track (ZFT) analyses of the sandstones sampled from Neoproterozoic to Middle Jurassic sequences, and further discusses their relation with low-temperature tectonic evolution and sediment provenance. The totally annealed ZFT data of 452–377 Ma from the Neoproterozoic and Devonian sandstones were related to an Early Paleozoic low-temperature exhumation of the Jiangnan orogen due to intracontinental orogeny in the South China block. Those annealed ZFT components from Triassic to Jurassic sandstones, grouped 236–189 Ma, 189–142 Ma, and 142–124 Ma decreasingly from east to west structurally imply a northwestward progressively squeezing by the Xuefeng intracontinental orogeny as a result of the Paleo-Pacific subduction. The unannealed age components (411 Ma, 362–377 Ma, 270–216 Ma, and 209–183 Ma) of the Upper Triassic to Middle Jurassic sandstones, are comparable to the multistage tectonic evolution of the Qinling orogen through subduction, accretion and collision and are therefore indicative of sample potential provenance. [ABSTRACT FROM AUTHOR]

Abstract: The Tongbai–Dabie–Sulu orogen contains several eclogite-bearing terranes that were largely metamorphosed in Triassic time. Although petrologic and geochronologic data from these terranes have provided essential information on the geodynamic history of the orogenic cycle, the timing of onset of continental collision between Sino–Korean craton and the Yangtze craton is still unknown. To better our understanding of the transitional time of oceanic to continental subduction in this orogen, we have dated an eclogite with continental affinity in the Tongbai Mountains, located in the very west part of the Tongbai–Dabie–Sulu orogen, central China, using Lu–Hf geochronology. These eclogites formed at pressure temperature conditions of 1.8–2.1GPa and 490–540°C. Mineral–whole rock ages of multi-garnet fractions from three localities yield Lu–Hf ages of 256.4±2.6Ma, 252.3±3.4Ma and 246.9±3.2Ma. Garnet porphyroblasts from the three samples display evidence of prograde zoning but the major portion of the garnet grains grew exclusively at eclogite-facies conditions due to the occurrence of omphacite inclusions from core to rim. Taking the spherical geometry effect into account, these Lu–Hf ages are, therefore, interpreted to reflect high-pressure eclogite-facies metamorphism instead of the early phase of garnet growth despite the well-preserved prograde major- and trace-element zoning in garnets. Our results allow for a more detailed and complete picture of the tectonic evolution of the Tongbai–Dabie–Sulu orogen during the transitional time of oceanic to continental subduction. These new Lu–Hf ages mark the timing of onset of continental collision between Sino–Korean craton and the Yangtze craton, suggesting that the entry of the leading edge of the Yangtze craton continent into the Sino–Korean craton trench occurred no later than ca. 256Ma. [Copyright &y& Elsevier]

Abstract: Low-temperature and high-pressure eclogites with an oceanic affinity in the western part of the Dabie orogen have been investigated with combined Lu–Hf and U–Pb geochronology. These eclogites formed over a range of temperatures (482–565°C and 1.9–2.2GPa). Three eclogites, which were sampled from the Gaoqiao country, yielded Lu–Hf ages of 240.7±1.2Ma, 243.3±4.1Ma and 238.3±1.2Ma, with a corresponding lower-intercept U–Pb zircon age of 232±26Ma. Despite the well-preserved prograde major- and trace-element zoning in garnets, these Lu–Hf ages mostly reflect the high-pressure eclogite-facies metamorphism instead of representing the early phase of garnet growth due to the occurrence of omphacite inclusions from core to rim and the shell effect. An upper-intercept zircon U–Pb age of 765±24Ma is defined for the Gaoqiao eclogite, which is consistent with the weighted-mean age of 768±21Ma for the country gneiss. However, the gneiss has not been subjected to successive high-pressure metamorphism. The new Triassic ages are likely an estimate of the involvement of oceanic fragments in the continental subduction. [Copyright &y& Elsevier]

Specific bacterial species have been found to play important roles in human vagina. Achieving high species-level resolution is vital for analyzing vaginal microbiota data. However, contradictory conclusions were yielded from different methodological studies. More comprehensive evaluation is needed for determining an optimal pipeline for vaginal microbiota. Based on the sequences of vaginal bacterial species downloaded from NCBI, we conducted simulated amplification with various primer sets targeting different 16S regions as well as taxonomic classification on the amplicons applying different combinations of algorithms (BLAST+, VSEARCH, and Sklearn) and reference databases (Greengenes2, SILVA, and RDP). Vaginal swabs were collected from participants with different vaginal microecology to construct 16S full-length sequenced mock communities. Both computational and experimental amplifications were performed on the mock samples. Classification accuracy of each pipeline was determined. Microbial profiles were compared between the full-length and partial 16S sequencing samples. The optimal pipeline was further validated in a multicenter cohort against the PCR results of common STI pathogens. Pipeline V1-V3_Sklearn_Combined had the highest accuracy for classifying the amplicons generated from both the NCBI downloaded data (84.20% ± 2.39%) and the full-length sequencing data (95.65% ± 3.04%). Vaginal samples amplified and sequenced targeting the V1-V3 region but merely employing the forward reads (223 bp) and classified using the optimal pipeline, resembled the mock communities the most. The pipeline demonstrated high F1-scores for detecting STI pathogens within the validation cohort. We have determined an optimal pipeline to achieve high species-level resolution for vaginal microbiota with short amplicons, which will facilitate future studies.IMPORTANCEFor vaginal microbiota studies, diverse 16S rRNA gene regions were applied for amplification and sequencing, which affect the comparability between different studies as well as the species-level resolution of taxonomic classification. We conducted comprehensive evaluation on the methods which influence the accuracy for the taxonomic classification and established an optimal pipeline to achieve high species-level resolution for vaginal microbiota with short amplicons, which will facilitate future studies., Competing Interests: The authors declare no conflict of interest.

In order to improve the wearing comfort and bearing effectiveness of the exoskeleton, based on the prototype and working mechanism analysis of a relaxation wearable system for knee exoskeleton robot, the static optimization synthesis and its method are studied. Firstly, based on the construction of the virtual prototype model of the system, a comprehensive wearable comfort evaluation index considering the factors such as stress, deformation and the proportion of stress nodes was constructed. Secondly, based on the static simulation and evaluation index of system virtual prototype, multi-objective genetic optimization and local optimization synthesis of armor layer topology were carried out. Finally, the model reconstruction simulation data confirmed that the system had good wearing comfort. Our study provides a theoretical basis for the bearing performance and prototype construction of the subsequent wearable system.