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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]

Abstract: The northeastern South China Sea continental margin holds the key to understanding Late Mesozoic tectonics and evaluating hydrocarbon potentials in Mesozoic tectonic and stratigraphic structures offshore southeast China. With newly obtained and processed seismic data, and new drilling and logging data, we correlate regional Mesozoic stratigraphy and analyze major Mesozoic tectonic events and structures. In particular, we focus our study on the three major tectonic units in the area, the Chaoshan Depression, the Tainan Basin, and the Dongsha–Penghu Uplift, which are separated by basement high, thrust fold, and (or) faults. Stratigraphic correlations suggest a major phase of southeastward regression, spanning in time from the late Early Jurassic (∼180Ma) to the Early Cretaceous (∼120Ma). Seismic data reveal two major tectonic events, with the first one in the Late Jurassic to the Early Cretaceous, contemporary with the regression, and the second one in the Late Cretaceous. Regional magnetic anomaly map after the reduction to the pole clearly reveals the boundary between the Dongsha–Penghu Uplift and the Chaoshan–Tainan depositional system. The seismic and magnetic data also suggest that, while the Dongsha–Penghu Uplift has highly magnetized sources buried mostly in the upper crust at depths from about 2km to about 20km, the Chaoshan–Tainan depositional system has thick Mesozoic sediments of low magnetization. [Copyright &y& Elsevier]

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]

• A novel passive knee exoskeleton with inclusivity in uncertainties • Propose a method for analysis human-exoskeleton with uncertainties • Propose an indicator to quantify the exoskeletons' motion transmission smoothness • Smoothness indicator consider only configuration variables It is suggested that exoskeletons may present challenges in terms of wearability due to unexpected human-machine interaction forces, usually caused by wearing uncertainties such as wearing slips, geometric differences in individual knees, and variable-axis knee movements. Additionally, the forces caused by drastic changes in velocity during exoskeleton locomotion may also be a contributing factor. To address these issues, this paper introduces a new passive knee exoskeleton and its human-machine wearing parallel (HMWP) research prototype to compensate and accommodate these uncertainties. Subsequently, a response interval analysis method based on Chebyshev functions is proposed to investigate the effect of uncertainties on the HMWP system's kinematic performance. In order to enhance the motion transmission smoothness, a new kinematic performance evaluation indicator is proposed, which considers solely the exoskeleton-configuration parameters. The response interval analysis method and new indicator are applied together in kinematic dimensional synthesis, resulting in significant improvements in the exoskeleton's kinematic performance. Furthermore, a parameter sensitivity analysis is conducted to facilitate more effective improvements to the exoskeleton's comfort. This research can also be used to improve the wearability of other wearable devices. [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]

Compared to the northern South China Sea continental margin, the deep structures and tectonic evolution of the Palawan and Sulu Sea and ambient regions are not well understood so far. However, this part of the southern continental margin and adjacent areas embed critical information on the opening of the South China Sea (SCS). In this paper, we carry out geophysical investigations using regional magnetic, gravity and reflection seismic data. Analytical signal amplitudes (ASA) of magnetic anomalies are calculated to depict the boundaries of different tectonic units. Curie-point depths are estimated from magnetic anomalies using a windowed wavenumber-domain algorithm. Application of the Parker–Oldenburg algorithm to Bouguer gravity anomalies yields a 3D Moho topography. The Palawan Continental Block (PCB) is defined by quiet magnetic anomalies, low ASA, moderate depths to the top and bottom of the magnetic layer, and its northern boundary is further constrained by reflection seismic data and Moho interpretation. The PCB is found to be a favorable area for hydrocarbon exploration. However, the continent–ocean transition zone between the PCB and the SCS is characterized by hyper-extended continental crust intruded with magmatic bodies. The NW Sulu Sea is interpreted as a relict oceanic slice and the geometry and position of extinct trench of the Proto South China Sea (PSCS) is further constrained. With additional age constraints from inverted Moho and Curie-point depths, we confirm that the spreading of the SE Sulu Sea started in the Early Oligocene/Late Eocene due to the subduction of the PSCS, and terminated in the Middle Miocene by the obduction of the NW Sulu Sea onto the PCB. [ABSTRACT FROM AUTHOR]

Abstract: Eclogites from the Huwan shear zone in the western Dabie were investigated in terms of their P–T evolution, geochemistry, and combined Lu–Hf and Sm–Nd geochronology. Trace element and isotope data suggest a normal mid-ocean ridge rather than an intraplate or ocean island setting for the protoliths of the eclogites. Electron microprobe analyses of representative garnets show typical prograde zoning profiles. Estimated peak metamorphic temperatures of 540–590°C most likely did not exceed the closure temperature of the Lu–Hf and Sm–Nd systems. The consistent Lu–Hf and Sm–Nd ages, therefore, most likely reflect garnet growth and are interpreted to reflect high-pressure eclogite-facies metamorphism due to the occurrence of omphacite inclusions from core to rim in garnets and the spherical geometry effect despite the well-preserved prograde zoning in the garnets. The high-pressure mineral assemblage of the eclogite yielded a statistically robust Lu–Hf age of 260.0±1.0Ma (2σ, 10 points, MSWD=1.0) and a Sm–Nd age of 260.4±2.0Ma (2σ, 9 points, MSWD=1.4), which are younger than the Carboniferous zircon U–Pb ages of ca. 310Ma. The new Lu–Hf and Sm–Nd data, in combination with published geochronological data, define two distinct Carboniferous and Permian population ages for the oceanic-type eclogites from the Huwan shear zone, which may require that these rocks experienced two episodes of high-pressure metamorphism within less than 50Myr. [Copyright &y& Elsevier]

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]