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Lithologically, two kinds of chert can be recognized in the Middle-Upper Permian from the Tieqiao section in Laibin area, Guangxi, i.e., calcic chert occurring mainly in the Maokou Formation and pure chert mainly in the Wujiaping Formation. Geochemical data show that both kinds of chert contain very low AlO (0-0.23%) and TiO (0.001%-0.024%) and low ΣREE (0.55-19.94 ppm, averaging 9.97 ppm), as well as high ratio of FeO/TiO (17-443, averaging 111) and low ratio of AlO/(AlO+FeO) (0-0.26, averaging 0.09). Given that the average value Ce anomalies in chert deposited in the ridge-proximal environment is about 0.29, and that in the pelagic environment is about 0.60, the low Ce anomalies in the Tieqiao chert (0.24-0.46, averaging 0.35) imply that they were deposited in an ocean basin with influence of submarine hydrothermal fluid and no input of terrigenous materials. The vertical variation of the silica abundance in strata (SAIS) in the Middle-Upper Permian strata, together with the Eu anomalies and the ratios of σREE/Fe, indicates a relationship between the hydrothermal activity and the Emeishan basalt eruption, and that submarine hydrothermal activity was stronger in the Upper Permian (the Wujiapingian Stage) than in the Middle Permian (the Maokou Stage). [ABSTRACT FROM AUTHOR]

Unlike most Precambrian cratons that have thick sub-continental lithospheric roots, the Archean lithosphere beneath the North China Craton is thin (reduced from 200 km to about 80 km), and has been replaced by a geochemically juvenile lithospheric mantle. This is a unique regional geological event, which has attracted worldwide attention. In the North China Block, Late Mesozoic extensional tectonics is evident by low-angle detachment faults, syntectonic plutons bounded by ductile faults, metamorphic core complexes (MCC) and widespread Jurassic to Cretaceous half-grabens filled by continental terrigenous deposits and volcanic rocks. At a regional scale, these structures share the same NW-SE extensional direction, while maintaining their own individual kinematics. In other words, the MCC feature a top-to-the-NW sense of shear, and syntectonic plutons are typified by a top-to-the-SE shearing deformations. Geochronological results indicate that the extensional structures were formed between 130-120 Ma. These extensional events lead to magmatic rock emplacement, distributed at the footwall of the detachment faults. Two different exhumation stages can be identified based on regional structural and magmatic interpretation: a Jurassic slow or negligible exhumation and a Cretaceous fast one assisted by normal faulting. These two cooling stages correspond to distinct geodynamic processes that occurred during the Jurassic and Cretaceous. Extensional tectonics appear to have been insignificant before the Early Cretaceous, and the process may be demonstrated by partial melting of the crust. The second stage, dominated by an extensional regime, developed after ca 120 Ma, and is tentatively correlated with crustal extension caused by lithospheric removal of the North China Craton. [ABSTRACT FROM AUTHOR]

The present-day topography of the Tian Shan range is considered to result from crustal shortening related to the ongoing India-Asia collision that started in the early Tertiary. In this study we report evidence for several episodes of localized tectonic activity which occurred prior to that major orogenic event. Apatite fission track analysis and (U-Th)/He dating on apatite and zircon indicate that inherited Paleozoic structures were reactivated in the late Paleozoic-early Mesozoic during a Cimmerian orogenic episode and also in the Late Cretaceous-Paleogene (around 65-60 Ma). These reactivations could have resulted from the accretion of the Kohistan-Dras arc or lithospheric extension in the Siberia-Mongolia zone. Activity resumed in the late Mesozoic prior to the major Tertiary orogenic phase. Finally, the ongoing deformation, which again reactivates inherited tectonic structures, tends to propagate inside the endoreic basins that were preserved in the range, leading to their progressive closure. This study demonstrates the importance of inherited structures in localizing the first increments of the deformation before it propagates into yet undeformed areas. [ABSTRACT FROM AUTHOR]

The Chinese Tianshan is one of the important international natural laboratories for studying continental geodynamics, but its uplift time, kinematics and mechanism of formation are key unresolved questions. In order to constrain the timing, kinematics and mechanism of uplift of the Chinese Tianshan, we applied sedimentary petrography and apatite fission-track dating to Cretaceous-Tertiary series from the northern Tarim Basin and the Tianshan Mountains. We collected and analyzed 79 sandstone samples and 75 detrital heavy mineral samples from the Kezilenuer-Kuqa profile (northern Tarim Basin) with a well-defined magnetostratigraphy. Our data indicate that detrital mineral maturity abruptly decreased at the disconformity between the Upper and Lower Cretaceous, and decreased again after 15(−12) Ma. The sediments in the northern Tarim Basin changed their provenance at 124 Ma, 26(−24) Ma and 15(−12) Ma, respectively. In addition, we collected and analyzed 36 primary apatite samples from the South, Central and North Tianshan. Our results show that the Chinese Tianshan underwent three phases of differential uplift. The first phase of uplift started at the southern Central Tianshan during the Early Cretaceous and propagated southward. The second phase of uplift started at the northern Central Tianshan during the Late Cretaceous and propagated also southward. The third phase of uplift started at the northern Central Tianshan during the Eocene and propagated both northward and southward. These differential uplifts have caused development of disconformity and drops in mineral maturity of detrital sediments in the northern Tarim Basin. Such a differential and heterogeneous uplift process might have been trigged by collisions of different microcontinents (i.e., Lhasa, Kohistan-Dras and India) at the southern margin of Asia. These collisions reactivated the South Tianshan Fault and then the North Tianshan Suture, and uplifted the Chinese Tianshan step by step. [ABSTRACT FROM AUTHOR]

The south-western Chinese Tianshan orogenic belt is famous for its omphacite-bearing blueschists and associated eclogite-facies metavolcanic rocks. Although numerous petrologic, geochemical and geochronological studies are available, structural data and interpretations are still rare. This paper provides new structural data, including bulk geometry of structures and kinematic analyses, based on field and laboratory studies along the Akyazhi, Keburt and Muzaert Rivers. The study area is divided into three tectonic units, namely (1) a Southern Unit composed of weakly metamorphosed sedimentary rocks of Silurian age; (2) a Central HP/LT Unit composed of blueschist-eclogite-facies metamorphic rocks derived from basalts, pelites and volcaniclastic rocks; (3) a Northern Unit, which consists of a Carboniferous magmatic arc developed upon an amphibolite-facies metamorphic continental basement. Our structural analysis documents a polyphase deformation. The main event (D1) is reflected by Devonian to Carboniferous top-to-the northwest ductile shearing, coeval with HP/LT metamorphism. This is followed by north-directed thrusting (D2) of the Southern Unit over the Central HP/LT Unit, coeval with retrogression of the high-pressure rocks. A top-to-the-S (SE) deformation (D3) overprints the earliest events and is observed in the Northern and Central Units. Lastly, Permian dextral ductile-brittle wrenching (D4) overprints the older flat-lying fabrics. D4 is conspicuous along the Nalati Fault that separates the Northern Unit from the Central HP/LT Unit. The absolute timing of these deformation events is discussed in the light of available radiometric dating. The structural, metamorphic and geochronological data are integrated into a geodynamic model of the south-western Chinese Tianshan that emphasizes south-directed subduction of microcontinents located between Tarim and Junggar. [ABSTRACT FROM AUTHOR]

The Tian Shan Mountains constitute central Asia's longest and highest mountain range. Understanding their Cenozoic uplift history thus bears on mountain building processes in general, and on how deformation has occurred under the influence of the India-Asia collision in particular. In order to help decipher the uplift history of the Tian Shan, we collected 970 samples for magnetostratigraphic analysis along a 4571-m-thick section at the Jingou River (Xinjiang Province, China). Stepwise alternating field and thermal demagnetization isolate a linear magnetization component that is interpreted as primary. From this component, a magnetostratigraphic column composed of 67 polarity chrons are correlated with the reference geomagnetic polarity timescale between ∼1 Ma and ∼23.6 Ma, with some uncertainty below ∼21 Ma. This correlation places precise temporal control on the Neogene stratigraphy of the southern Junggar Basin and provides evidence for two significant stepwise increases in sediment accumulation rate at ∼16-15 Ma and ∼11-10 Ma. Rock magnetic parameters also undergo important changes at ∼16-15 Ma and ∼11-10 Ma that correlate with changes in sedimentary depositional environments. Together with previous work, we conclude that growth history of the modern Tian Shan Mountains includes two pulses of uplift and erosion at ∼16-15 Ma and ∼11-10 Ma. Middle to upper Tertiary rocks around the Tian Shan record very young (<∼5 Ma) counterclockwise paleomagnetic rotations, on the order of 15° to 20°, which are interpreted as because of strain partitioning with a component of sinistral shear that localized rotations in the piedmont. [ABSTRACT FROM AUTHOR]

The trace element and rare earth element (REE) variations across the Ordovician-Silurian succession are presented from two outcrop sections on the Yangtze Platform: the Nanbazi section, Guizhou Province, deposited in a shallow platform interior setting, and the Wangjiawan section, Hubei Province, deposited in a deeper basinal environment. Geochemical analysis of closely spaced samples through three intervals, the Wufeng, Guanyinqiao and Longmaxi, revealed vast palaeoceanographic changes. Some geochemical proxies, including Th/U, Ni/Co, V/Cr, and V/(V+Ni) ratios, together with sedimentary facies and biotic data, indicate that an anoxic condition on the most of the Yangtze Platform during the Wufeng and Longmaxi intervals, but an oxic condition during the Guanyinqiao time. The shift of the anoxic to the oxic environment during the Guanyinqiao time coincided with a global sea-level lowstand, in parallel with the global glaciation. The Longmaxian anoxic environment was a result of a global sea-level rise, which may be synchronized with a mainly catastrophic event in the latest Ordovician. Although the two sections generally show similar variation patterns of trace and REE concentrations and some element ratios, a minor difference occurs between the Wangjiawan and Nanbazi sections, likely reflecting a difference in depositional setting during the accumulation. Such an oceanic oxygen-level variation may add a useful constraint to the current arguments on the cause and consequence of the latest Ordovician mass extinction. [ABSTRACT FROM AUTHOR]

The Yunkai massif is a key region to decipher the tectonic evolution of the south China block since the contained high-grade metamorphic rocks experienced a polyphase deformation. The earliest event (D1) corresponds to a top-to-the-northwest ductile shearing, coeval with amphibolite facies metamorphism, probably developed during a postorogenic synmigmatization extensional event occurred in early Paleozoic time. The main ductile deformation (D2) is top-to-the-northeast shearing, occurred in early Mesozoic time, coeval with amphibolite to greenschist facies metamorphism and associated with the development of northeast verging recumbent folds within the Neoproterozoic-Paleozoic sedimentary cover of the south China block. The tectonic significance of D2 is possibly linked with the subduction of Indochina beneath south China along the Song Ma belt of North Vietnam. Another compressional event (D3) of Late Jurassic to Cretaceous age is indicated by SE verging recumbent folds with NE-SW trending axes developed both in the sedimentary cover and gneissic basement. The northwestward subduction of the Pacific plate or the SE thrusting of the Songpan-Ganzi fold belt upon the Yangtze craton can be considered as the geodynamic causes of this late Mesozoic event. Last, NE-SW trending brittle sinistral strike-slip and normal faulting (D4) control the massif uplifting and the subsiding of continental half grabens. This structure, which is widespread in the eastern margin of the Eurasia continent, can be related either to the westward subduction of the Paleo-Pacific plate or to lithosphere removal during the late Mesozoic. [ABSTRACT FROM AUTHOR]

Abstract There are some quite different disputes about chronostratigraphic division of the Cretaceous in the Kuqa Depression, northern margin of the Tarim Basin. We then carried on a magnetostratigraphic study on Cretaceous succession in the Kuqa River and Kezilenuer Channel profiles. Detailed paleomagnetic analyses on 446 specimens from 265 sites permit a construction of a preliminary magnetic polarity sequence for the Cretaceous strata. Together with paleobiologic constraints from calcareous nannofossils, magnetostratigraphic results show that the Bashenjiqike Formation was probably deposited during the late Campanian to Maastrichtian stages of the Late Cretaceous, ranging from about 79.1 to 65.6 Ma. On the other hand, magnetozones identified from the Yageliemu, Shushanhe, and Baxigai formations may principally correlate with chrons M18r to M3 of the Geomagnetic Polarity Time Scale (GPTS). This correlation suggests that these three formations were very likely to be formed during the early-middle stage of the Early Cretaceous between the Berriasian to the early Berremian stages (141.9-124.1 Ma). Therefore it is possible that the Bashenjiqike Formation contacts the underlying strata with an unconformity and there is a giant sedimentary hiatus during the period of the late Barremian to early Maastrichtian stages in the Kuqa Depression. [ABSTRACT FROM AUTHOR]

Field investigation shows that the boundary between the Kuqa Basin and the Tianshan Mountains can be divided into two sections with the Yanbulak area as the dividing point. In the western section, the Mesozoic strata overlie unconformably on the Paleozoic rocks. The basin-dipping faults developed in both Mesozoic and Paleozoic rocks. The eastern section is characterized by basin-dipping normal faults separating the Paleozoic strata and Tertiary. The brittle structural analysis was carried out along the basin-range boundary. 360 measurements of striations have been obtained at a total of 25 sites. Paleostress reconstruction indicates that the basin-range boundary was in an extensional condition, with some superimposed strike-slip, during the Late Tertiary. The extension could be explained by the vertical block uplift of the Tianshan Mountains. [ABSTRACT FROM AUTHOR]

Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area. [ABSTRACT FROM AUTHOR]

Examines the uranium-lead isotope composition of rutile, omphacite and garnets in the eclogite in China. Determination of the cooling ages of minerals in ultrahigh-pressure metamorphic rocks; Performance of magnetic and heavy liquid separations; Completion of the chemical and mass-spectrometric analyses.

Reports the discovery of metamorphic slabs within metamorphic eclogite complexes in China. Discussion on volcanic clastic rock; Conclusion.

Histone lactylation is a metabolic stress‐related histone modification. However, the role of histone lactylation in the development of sepsis‐associated acute kidney injury (SA‐AKI) remains unclear. Here, histone H3K18 lactylation (H3K18la) is elevated in SA‐AKI, which is reported in this study. Furthermore, this lactate‐dependent histone modification is enriched at the promoter of Ras homolog gene family member A (RhoA) and positively correlated with the transcription. Correction of abnormal lactate levels resulted in a reversal of abnormal histone lactylation at the promoter of RhoA. Examination of related mechanism revealed that histone lactylation promoted the RhoA/Rho‐associated protein kinase (ROCK) /Ezrin signaling, the activation of nuclear factor‐κB (NF‐κB), inflammation, cell apoptosis, and aggravated renal dysfunction. In addition, Ezrin can undergo lactylation modification. Multiple lactylation sites are identified in Ezrin and confirmed that lactylation mainly occurred at the K263 site. The role of histone lactylation is revealed in SA‐AKI and reportes a novel post‐translational modification in Ezrin. Its potential role in regulating inflammatory metabolic adaptation of renal proximal tubule epithelial cells is also elucidated. The results provide novel insights into the epigenetic regulation of the onset of SA‐AKI. [ABSTRACT FROM AUTHOR]

Background: Human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) is a heterogeneous GC subtype characterized by the overexpression of HER2. To date, few specific targeted therapies have demonstrated durable efficacy in HER2-positive GC patients, with resistance to trastuzumab typically emerging within 1 year. However, the mechanisms of resistance to trastuzumab remain incompletely understood, presenting a significant challenge to clinical practice. Methods: In this study, we integrated genetic screening and bulk transcriptome and epigenomic profiling to define the mechanisms mediating adaptive resistance to HER2 inhibitors and identify potential effective therapeutic strategies for treating HER2-positive GCs. Results: We revealed a potential association between adaptive resistance to trastuzumab in HER2-positive GC and the expression of YES-associated protein (YAP). Notably, our investigation revealed that long-term administration of trastuzumab triggers extensive chromatin remodeling and initiates YAP gene transcription in HER2-positive cells characterized by the initial inhibition and subsequent reactivation. Furthermore, treatment of HER2-positive GC cells and cell line-derived xenografts (CDX) models with YAP inhibitors in combination with trastuzumab was found to induce synergistic effects through the AKT/mTOR and ERK/mTOR pathways. Conclusion: These findings underscore the pivotal role of reactivated YAP and mTOR signaling pathways in the development of adaptive resistance to trastuzumab and may serve as a promising joint target to overcome resistance to trastuzumab. [ABSTRACT FROM AUTHOR]

Summarizes the result of a multidisciplinary study on the Dabie Orogen and Hefei Basin. Petrotectonic division in the Dabie Mountains and Hefei Basin; Deep structure of the Dabie Orogen and Hefei Basin; Evolution of the Dabie Orogen and Hefei Basin; Discussion on the geodynamics of the mountain-building and basin-forming process; Concluding remarks.

Antiphospholipid syndrome (APS) is characterized by thrombus formation, poor pregnancy outcomes, and a proinflammatory response. H3K4me3‐related monocytes activation are key regulators of APS pathogenesis. Therefore, H3K4me3 CUT&Tag and ATAC‐seq are performed to examine the epigenetic profiles. The results indicate that the H3K4me3 signal and chromatin accessibility at the FOXJ2 promoter are enhanced in an in vitro monocyte model by stimulation with β2GPI/anti‐β2GPI, which mimics APS, and decreases after OICR‐9429 administration. Furthermore, FOXJ2 is highly expressed in patients with primary APS (PAPS) and is the highest in patients with triple‐positive antiphospholipid antibodies (aPLs). Mechanistically, FOXJ2 directly binds to the SLAMF8 promoter and activates SLAMF8 transcription. SLAMF8 further interacts with TREM1 to stimulate TLR4/NF‐κB signaling and prohibit autophagy. Knockdown of FOXJ2, SLAMF8, or TREM1 blocks TLR4/NF‐κB and provokes autophagy, subsequently inhibiting the release of inflammatory and thrombotic indicators. A mouse model of vascular APS is established via β2GPI intraperitoneal injection, and the results suggest that OICR‐9429 administration attenuates the inflammatory response and thrombus formation by inactivating FOXJ2/SLAMF8/TREM1 signaling. These findings highlight the overexpression of H3K4me3‐mediated FOXJ2 in APS, which consequently accelerates APS pathogenesis by triggering inflammation and thrombosis via boosting the SLAMF8/TREM1 axis. Therefore, OICR‐9429 is a promising candidate drug for APS therapy. [ABSTRACT FROM AUTHOR]

Background: Alterations of the trimethylation of histone 3 lysine 4 (H3K4me3) mark in monocytes are implicated in the development of autoimmune diseases. Therefore, the purpose of our study was to elucidate the role of H3K4me3‐mediated epigenetics in the pathogenesis of antiphospholipid syndrome (APS). Methods: H3K4me3 Cleavage Under Targets and Tagmentation and Assay for Transposase‐Accessible Chromatin were performed to determine the epigenetic profiles. Luciferase reporter assay, RNA immunoprecipitation, RNA pull‐down, co‐immunoprecipitation and chromatin immunoprecipitation were performed for mechanistic studies. Transmission electron microscopy and propidium iodide staining confirmed cell pyroptosis. Primary monocytes from patients with primary APS (PAPS) and healthy donors were utilised to test the levels of key molecules. A mouse model mimicked APS was constructed with beta2‐glycoprotein I (β2GPI) injection. Blood velocity was detected using murine Doppler ultrasound. Results: H3K4me3 signal and open chromatin at the ARID5B promoter were increased in an in vitro model of APS. The epigenetic factor ARID5B directly activated LINC01128 transcription at its promoter. LINC01128 promoted the formation of the BTF3/STAT3 complex to enhance STAT3 phosphorylation. Activated STAT3 interacted with the NLRP3 promoter and subsequently stimulated pyroptosis and apoptosis. ARID5B or BTF3 depletion compensated for LINC01128‐induced pyroptosis and apoptosis by inhibiting STAT3 phosphorylation. In mice with APS, β2GPI exposure elevated the levels of key proteins of pyroptosis and apoptosis pathways in bone marrow‐derived monocytes, reduced the blood velocity of the ascending aorta, increased the thrombus size of the carotid artery, and promoted the release of interleukin (IL)‐18, IL‐1β and tissue factor. Patients with PAPS had the high‐expressed ARID5B and LINC01128, especially those with triple positivity for antiphospholipid antibodies. Moreover, there was a positive correlation between ARID5B and LINC01128 expression. Conclusion: This study indicated that ARID5B/LINC01128 was synergistically upregulated in APS, and they aggravated disease pathogenesis by enhancing the formation of the BTF3/STAT3 complex and boosting p‐STAT3‐mediated pyroptosis and apoptosis, thereby providing candidate therapeutic targets for APS. Highlights: The H3K4me3 mark and chromatin accessibility at the ARID5B promoter are increased in vitro model mimicked APS.ARID5B‐mediated LINC01128 induces pyroptosis and apoptosis via p‐STAT3 by binding to BTF3.ARID5B is high‐ expressed in patients with primary APS and positively correlated with LINC01128 expression.OICR‐9429 treatment mitigates pyroptosis and related inflammation in vivo and in vitro models mimicked APS. [ABSTRACT FROM AUTHOR]

Highlights: The first construct of a multi-field-coupled synergistic ion transport system (MSITS) in Li+ extraction is proposed. Effectively suppress the ion concentration polarization effect of the ion-enrichment zone at the membrane interface. The MSITS equipped with heterogeneous membrane exhibited outstanding separation performance with Li+ flux of 367.4 mmol m−2 h−1 and Li+/Co2+ selectivity of 216,412, outperforming previous reports. The global carbon neutrality strategy brings a wave of rechargeable lithium‐ion batteries technique development and induces an ever-growing consumption and demand for lithium (Li). Among all the Li exploitation, extracting Li from spent LIBs would be a strategic and perspective approach, especially with the low energy consumption and eco-friendly membrane separation method. However, current membrane separation systems mainly focus on monotonous membrane design and structure optimization, and rarely further consider the coordination of inherent structure and applied external field, resulting in limited ion transport. Here, we propose a heterogeneous nanofluidic membrane as a platform for coupling multi-external fields (i.e., light-induced heat, electrical, and concentration gradient fields) to construct the multi-field-coupled synergistic ion transport system (MSITS) for Li-ion extraction from spent LIBs. The Li flux of the MSITS reaches 367.4 mmol m−2 h−1, even higher than the sum flux of those applied individual fields, reflecting synergistic enhancement for ion transport of the multi-field-coupled effect. Benefiting from the adaptation of membrane structure and multi-external fields, the proposed system exhibits ultrahigh selectivity with a Li+/Co2+ factor of 216,412, outperforming previous reports. MSITS based on nanofluidic membrane proves to be a promising ion transport strategy, as it could accelerate ion transmembrane transport and alleviate the ion concentration polarization effect. This work demonstrated a collaborative system equipped with an optimized membrane for high-efficient Li extraction, providing an expanded strategy to investigate the other membrane-based applications of their common similarities in core concepts. [ABSTRACT FROM AUTHOR]

Access to uranium resources is critical to the sustainable development of nuclear energy. The ocean contains abundant uranium resources, but the marine biological pollution and the low concentration of uranium make it a giant challenge to extract uranium from seawater. On the foundation of selective uranium adsorption using high uranium‐affinity groups, realizing the external‐field improved uranium capture without extra energy consumption is highly attractive. A solar thermal collector with 3D ion‐transport networks based on environmentally friendly biomass adsorption material is reported, which contains antibacterial adsorption ligands and photothermal graphene oxide. The antibacterial ability through an easy one‐step reaction and the fast mass transfer caused by photothermal conversion collaboratively improve the original adsorption capacity of the hydrogel by 46.7%, reaching 9.18 mg g−1 after contact with natural seawater for 14 days. This study provides a universal strategy for the design of physical‐fields‐enhanced hydrogel adsorbents. [ABSTRACT FROM AUTHOR]

In the past two years, several horizontal wells with ultra-long horizontal intervals were completed in Changqing oil and gas field. The longest horizon interval reached 4466 m, which set a record of the longest onshore horizontal well in Asia. There were a lot of difficulties such as high friction, mudstone collapse, and sand carrying that puzzled the drilling of wells with ultra-long horizontal intervals. To solve these problems, some key treatment agents were screened to form a novel water-based drilling fluid system (CQSP-RH). The yield point and extreme pressure lubrication coefficient of the novel system were 18 Pa and 0.058, respectively. The filtrate volume of the novel system was only 1.9 mL at room temperature and was 12 mL at 120 °C. When the cuttings were rolled for 16 h at 120 °C, the primary recovery of them could reach 98.64%. Subsequently, the novel system was applied to wells with ultra-long horizontal intervals. The friction resistance between drilling tools and sidewall was controlled within 500 KN; the solid contents of drilling fluid was controlled within 10%. The results proved that the novel system have superb properties and tremendous potential to drill deeper horizontal wells. [ABSTRACT FROM AUTHOR]

Background and objective: Morphological identification of peripheral leukocytes is a complex and time-consuming task, having especially high requirements for personnel expertise. This study is to investigate the role of artificial intelligence (AI) in assisting the manual leukocyte differentiation of peripheral blood. Methods: A total of 102 blood samples that triggered the review rules of hematology analyzers were enrolled. The peripheral blood smears were prepared and analyzed by Mindray MC-100i digital morphology analyzers. Two hundreds leukocytes were located and their cell images were collected. Two senior technologists labeled all cells to form standard answers. Afterward, the digital morphology analyzer unitized AI to pre-classify all cells. Ten junior and intermediate technologists were selected to review the cells with the AI pre-classification, yielding the AI-assisted classifications. Then the cell images were shuffled and re-classified without AI. The accuracy, sensitivity and specificity of the leukocyte differentiation with or without AI assistance were analyzed and compared. The time required for classification by each person was recorded. Results: For junior technologists, the accuracy of normal and abnormal leukocyte differentiation increased by 4.79% and 15.16% with the assistance of AI. And for intermediate technologists, the accuracy increased by 7.40% and 14.54% for normal and abnormal leukocyte differentiation, respectively. The sensitivity and specificity also significantly increased with the help of AI. In addition, the average time for each individual to classify each blood smear was shortened by 215 s with AI. Conclusion: AI can assist laboratory technologists in the morphological differentiation of leukocytes. In particular, it can improve the sensitivity of abnormal leukocyte differentiation and lower the risk of missing detection of abnormal WBCs. [ABSTRACT FROM AUTHOR]

The cause of magmatic tempo in an active plate margin remains controversial, partly due to lack of structural analysis. During 130–105 Ma, the magmatism in the South China Block (SCB) was significantly reduced (lull) and restricted around the Changle‐Nan'ao Belt (CNB) while the magmatism was highly active (flare‐up) in North China. For unveiling the tectonic role on magmatism, a multidisciplinary study including field and microscopic structural observations, magnetic fabric measurement (AMS), and zircon/monazite dating was conducted on the plutons with oriented minerals in the CNB. Structural analysis and AMS results show a highly clustered NE‐striking vertical foliation developed during the emplacement indicating a syn‐emplacement NW‐SE shortening regime. The geochronology results confirm that the emplacement occurred during 130–105 Ma. Regional geologic correlation indicates that the collision between the Dangerous Grounds‐West Philippines Block and SCB was responsible for this shortening regime. The collected depleted zircon εHf(t) data suggest that a possible collision‐triggered slab break‐off caused the syn‐collisional magmatic activity around the CNB. This study shows that the magmatic lull in the SCB was coeval with a crustal shortening regime due to the arrival of a microcontinent carried by the subduction slab, while the magmatic flare‐up was coeval with an extensional regime due to the subduction roll‐back and retreat as evidenced by the Cretaceous evolution of the SCB before and after the collision and that of North China which is unaffected by the collision. The cause of magmatic tempo in the continental margin is largely due to the tectonic evolution of underlain subduction slabs. Plain Language Summary: Magmatic activity is closely connected to human life as it provides us with useful metals, releases greenhouse gases, triggers natural hazards. It is necessary to explore what controls a magmatic activity. Several previous studies considered that a shortening regime with thickened crust causes strong magmatism (flare‐up). The South China Block (SCB) featured by alternating magmatic flare‐up and lulls, provides an appropriate research target to test this hypothesis. During the Cretaceous, the SCB was dominated by an extensional regime caused by the Paleo‐Pacific oceanic slab subduction. However, our structural analyses on the SCB document a shortening regime caused by the collision between the SCB and a microcontinent carried by the Paleo‐Pacific oceanic slab in the period of the Cretaceous. During the collision, the SCB was generally featured by a magmatic lull, although magmatic activity was only observed around the Changle‐Nan'ao Belt, probably caused by the break‐off of the subducted Paleo‐Pacific oceanic slab. Before and after the collision, the extensional regime caused by Paleo‐Pacific oceanic slab subduction was coeval with magmatic flare‐up. This study questions the previous claims and proposes that the tectonic evolution of the subducting slab may control the magmatic flare‐up and lull in the overlain active continental margin. Key Points: The 130–105 Ma syn‐tectonic plutons intruded the Changle‐Nan'ao Belt in a NW‐SE shortening regime caused by a microcontinent collisionThe shortening/extension regimes were coeval with magmatic lull/flare‐up in the East Asia Continental Margin during the CretaceousThe collision causing break‐off can account for the plutonism in the Changle‐Nan'ao Belt during the magmatic lull of the South China Block [ABSTRACT FROM AUTHOR]

• When the direct current voltage of the conductor and the electric field of thundercloud act together, the positive wire inhibits the corona discharge of the upper ground wire, while the negative wire enhances the discharge of the upper ground wire. • The influence of air humidity on corona discharge on the shield wire surface above the negative conductor is greater than that on the shield wire above the positive conductor. • The corona discharge current on the shield wire surface above the negative pole wire does not change much whenthe downgoing pilot channel is considered, but the corona discharge on the shield wire surface above the negativepole wire is intensified by the presence of natural wind, and the corona current value gradually increases. The atmospheric space electrical field has nonlinear distribution characteristics during thunderstorm activity, which influences the ground surface electric corona of UHV transmission lines. In this paper, the corona discharge model of ground wire of ±1100 kV UHVDC transmission line is established considering the combined effect of ground lightning process and working voltage. With the combined action of thundercloud electrical field and DC voltage, the positive conductor suppresses the electric corona of the upper shied wire, and the negative conductor enhances the discharge of the upper shied wire. The corona current of the right shied wire is 54.7 μA/m larger than that of the left shied wire. When the down leader develops, the leader voltage, the line operating voltage and the thundercloud voltage work together, and the electric corona on the surface of the conductor and shied wire of the transmission line increases rapidly. The corona current increases 102 times on the left shied wire's surface and 103 times on the right shied wire's. Considering the environmental factors and the development of the downgoing leader at the same time, the degree of electric corona on the surface of the shied wire is weakened when the humidity in the space increases, but the overall value of the corona current is much higher than the thundercloud electrical field. When the wind speed increases, the degree of electric corona on the surface of the shied wire is aggravated. The corona current on the surface of the left shied wire is 37.13 μA/m, and the one of the right shied wire is 109.33 μA/m. The corona current value of ground surface increases with the increase of wind direction. [ABSTRACT FROM AUTHOR]

Membrane protein clients of endoplasmic reticulum (ER)-associated degradation must be retrotranslocated from the ER membrane by the AAA-ATPase p97 for proteasomal degradation. Before direct engagement with p97, client transmembrane domains (TMDs) that have partially or fully crossed the membrane must be constantly shielded to avoid non-native interactions. How client TMDs are seamlessly escorted from the membrane to p97 is unknown. Here, we identified ER-anchored TMUB1 as a TMD-specific escortase. TMUB1 interacts with the TMD of clients within the membrane and holds ∼10–14 residues of a hydrophobic sequence that is exposed out of membrane, using its transmembrane and cytosolic regions, respectively. The ubiquitin-like domain of TMUB1 recruits p97, which can pull client TMDs from bound TMUB1 into the cytosol. The disruption of TMUB1 escortase activity impairs retrotranslocation and stabilizes retrotranslocating intermediates of client proteins within the ER membrane. Thus, TMUB1 promotes TMD segregation by safeguarding the TMD movement from the membrane to p97. [Display omitted] • TMUB1 promotes the p97-mediated extraction of membrane proteins from the ER • The UBL of TMUB1 directly recruits the p97-UFD1L-NPLOC4 complex • TMUB1 cytosolic domain captures a fragment of client TMD emerging from the ER membrane • P97 ATPase segregates the TMD fragment from TMUB1 cytosolic domain Wang et al. found that TMUB1 binds to p97 ATPase and facilitates p97-mediated membrane protein extraction from the endoplasmic reticulum (ER) membrane during ER-associated degradation. TMUB1 chaperones partly exposed hydrophobic transmembrane domains (TMDs) of client proteins in aqueous cytosol, thereby safeguarding TMD movement from the ER membrane to p97. [ABSTRACT FROM AUTHOR]

Abstract: The Ordo-Silurian transition was a critical interval in geological history, during which profound biotic, climatic and oceanic changes occurred. In order to explore the oceanic palaeoredox changes, multiple geochemical proxies, including ratios of S/C, FeHR/FeT, FeP/FeHR and DOP values, are presented here from three sections (Wangjiawan, western Hubei, Sanjiaguan, northern Hunan, and Nanbazi, northern Guizhou) across the Ordo-Silurian boundary on the Yangtze Platform. These palaeoredox data indicate a predominance of stratified, anoxic (ferruginous) ocean on the Yangtze block during this transition, which was interrupted by a brief episode of oceanic oxygenation in the early Hirnantian. This oxygenation, temporally coinciding with the end-Ordovician glaciation and global glacio-eustatic sea level fall, likely resulted from enhanced circulation of polar cold, dense oxygen-rich water onto the low-latitude shelf. The prior and subsequent longer-term episodes of anoxic ocean, particularly the later one which started in the late Hirnantian, occurred in parallel with the rapid climatic warming and sea level rise, which could have slowed down oceanic circulation, thereby enhancing oceanic stratification, anoxia and organic preservation. Oceanic redox changes, together with rapid climatic and sea-level fluctuations, were likely responsible for the stepwise massive demise of the Ordo-Silurian biotic crisis. [Copyright &y& Elsevier]

Abstract: The Tongcheng massif, a structure lying to the east of the central Dabieshan domain, previously considered a unique unit metamorphosed under Ultrahigh-Pressure (UHP) conditions, similar to those involved in the South Dabieshan and wrenched by the Tan–Lu fault during the Mesozoic. Detailed field survey and laboratory work in the areas of structural geology and petrology indicates that the Tongcheng massif is a tectonic stack of allochthonous sheets. From the bottom to the top, this massif is divided into three units: Lower, Middle and Upper Unit. The Lower Unit suffered an UHP metamorphism with a P-T condition of about 3.21–3.31 GPa and 590–651 °C. Eclogites in the Middle Unit underwent high pressure (HP) and medium temperature metamorphism at 2.46–2.64 GPa and 500–565 °C. In the Upper Unit, the peak metamorphic P-T conditions for eclogites were estimated as 1.54–2.36 GPa and 389–510 °C. These petrological results correspond well to the geometry of the field observation. Structural analysis indicates that the Tongcheng massif has experienced polyphase deformation. The earliest event (D1) corresponds to top-to-north (northeast) shearing associated with the early exhumation stages of HP-UHP rocks during the late Triassic. The D2 deformation overprints D1 and coincides with a domal structure similar to a metamorphic core complex of early Cretaceous age. The D3 deformation is expressed by a pervasive ENE-WSW trending, subvertical foliation and a subhorizontal lineation or penetrative slickenline with a sinistral sense of shear, probably related to the NE-SW contraction during the NW-SE subhorizontal extension, the strike slip deformation raised by the N-S compression during the early Cretaceous. The D4 event is represented by a brittle NE striking, moderately to steeply dipping to the SE fault with down-dip slickenlines. Kinematic indicators show a normal displacement with the east side moving downward. Half-grabens of late Cretaceous to early Cenozoic age are widespread throughout Eastern China. Based on structural analysis, mineral chemistry data and, in particular, the results of P-T calculations for eclogites in different units, a geodynamic scenario for the evolution of the HP-UHP orogenic belt of the Dabieshan is proposed, and the significance of the Tan–Lu fault is also discussed. [Copyright &y& Elsevier]

Abstract: Abundance of organic matter, carbon isotopic compositions of organic matter (δ 13Corg) and sulfur isotopic compositions of iron sulfide (δ 34Ssulfide) across the Ordovician–Silurian (O–S) boundary was analysed from two sections (Wangjiawan, western Hubei; Nanbazi, northern Guizhou) on the Yangtze Platform, South China. The organic abundance across the O–S boundary at these two sections is generally high, except for the Hirnantian interval. At Wangjiawan section in western Hubei, the δ 13Corg values vary from about −30.8‰ VPDB in the mid-Ashgill to −27.6‰ in the upper Hirnantian interval, which abruptly return to the pre-Hirnantian values. At Nanbazi section in northern Guizhou, δ 13Corg values vary from −30.5‰ to −26.6‰ from the mid-Ashgill to the upper Hirnantian horizons, which shift negatively to the low spike at −29.2‰ in the lowermost Rhuddanian, then increase slightly to relatively persistent values around −28‰. Similar variation patterns of δ 34Ssulfide values are unravelled at the two sections, showing a positive excursion from the mid-Ashgill to the upper Hirnantian, then a sharp negative shift in the lowermost Rhuddanian, although with different background values of δ 34Ssulfide from these two sections. These data, together with those from other areas, demonstrate large climatic fluctuations from warming to cooling, then to warming, oceanic changes from and anoxic to oxygenated, to anoxic water columns, during the O–S transition. Climatic fluctuations, together with multiple oceanic anoxia and sea-level fluctuations, were likely responsible for the stepwise massive demise of the O–S biotic crisis. [Copyright &y& Elsevier]

• Bavachin can inhibit TNF-α, IL-6, IL-1β and NLRP3 expression level. • Bavachin can upregulate the expression of A20 in microglial cells. • Bavachin can promote the assemble of A20 ubiquitin-editing complex. • Upregulation of A20 was involved in the inhibitory effects of bavachin on microglia activation via inhibition of NF-κB pathway. Neuroinflammation is a major pathophysiological contributor to the progression of the central nervous system disorders. Bavachin is a natural product belonging to the flavonoid class. The anti-neuroinflammatory effect and the molecular mechanisms are not well understood. In this study, we found bavachin can exert anti-neuroinflammatory effect via inhibition of nuclear factor-kappa B (NF-κB) signaling. We found that bavachin can obviously upregulate the expression of A20 (TNFAIP3) in microglial cells. Further studies suggested siRNA-A20 knockdown treatment can attenuate the inhibitory effects of bavachin on neuroinflammation. We further found bavachin can increase the interaction of ubiquitin-editing enzyme A20 complex including A20, Tax1-binding protein 1 (TAX1BP1) and Itch, the subsequently downregulated the K63-ubiquitination of TNF receptor associated factor 6 (TRAF6) and NF-κB signaling pathway. Altogether, our results indicated that bavachin exerted anti-neuroinflammatory effects through inhibition of NF-κB signaling mediated by regulation of ubiquitin-editing enzyme A20 complex. Our finding has important clinical significance for the potential application of bavachin in the treatment of neurological disorders. [ABSTRACT FROM AUTHOR]

The clinical application of cisplatin was mainly limited by severe nephrotoxicity. Danshensu was the main pharmacological active diterpenoids which extracted from the roots of Salvia milthiorriza Bunge. This study is aimed to investigate the protective effects and potential mechanisms of Danshensu against cisplatin-induced nephrotoxicity. After fasting for 12 h, all mice groups except the control group were administered a single intraperitoneal injection of 25 mg/kg cisplatin. 1 h later, cisplatin (25 mg/kg) + Danshensu (15 mg/kg, 30 mg/kg, 60 mg/kg) groups were treated with corresponding doses of Danshensu once a day for 7 consecutive days. Blood urea nitrogen (BUN), creatinine, reactive oxygen species (ROS), superoxide dismutase (SOD), Glutathione peroxidase (GPx), Catalase (CAT) and malondialdehyde (MDA) were assayed in this study. The expression of inflammatory cytokines TNF-α, IL-6 and IL-1β were examined by ELISA. The results showed that Danshensu could improve kidney damage, attenuate serum BUN, creatinine, cytokines and oxidative stress markers. Further studies showed that Danshensu can induce Nrf2/HO-1 activation and inhibition of NF-κB pathway. In conclusion, Danshensu exerts the protective effects on cisplatin-induced nephrotoxicity, which may be related to the activation of Nrf2/HO-1 and inhibition of NF-ĸB pathway. [Display omitted] • Danshensu ameliorated cisplatin-induced nephrotoxicity in mice. • Danshensu inhibited oxidative stress via activation of Nrf2/HO-1. • Danshensu exerted anti-inflammatory effects via inhibition of NF-κB pathway. • This study demonstrated a new insight into the effects and mechanism of Danshensu on cisplatin-induced nephrotoxicity. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a disease characterised by acute onset, high mortality, and poor prognosis, and is mainly caused by ischemia-reperfusion (I/R). Human urine-derived stem cells (USCs) exhibit antioxidant, anti-inflammatory, and anti-apoptotic cytoprotective effects. Previously, we found that exosomes from USCs had the ability to inhibit apoptosis and protect kidneys from I/R injury. This study aimed to investigate the role of USC-derived exosomes (USC-Exos) in reducing pyroptosis and alleviating I/R-AKI. Models of HK-2 cells hypoxia-reoxygenation (H/R) and I/R kidney injury was established in Sprague Dawley rats to simulate AKI in vitro and in vivo. USC-Exos were isolated using ultracentrifugation and identified via electron microscopy and western blotting. USC-Exos were co-cultured with HK-2 cells and injected into rats via the tail vein. The expression of pyroptosis-related molecules (GSDMD, caspase-1, and NLRP-3) was verified using PCR and western blotting. Changes in renal function were reflected in the serum creatinine, urea, and cystatin C levels. The degree of renal injury was determined using haematoxylin and eosin and immunohistochemical staining. The levels of IL-1β and IL-18 were detected using enzyme-linked immunosorbent assay (ELISA) to verify the role of USC-Exos in pyroptosis. Differentially expressed circRNAs in I/R rat kidneys were screened by transcriptome sequencing, and a dual-luciferase experiment was used to verify the interaction between upstream and downstream molecules. Ischemia-reperfusion resulted in significantly impaired renal function and expression of pyroptosis molecules, and significantly increased concentrations of inflammatory factors. These effects were reversed by injecting USC-Exos. Circ DENND4C was the most significantly decreased circRNA in I/R rat renal tissue, and knock-down of circ DENND4C can aggravate AKI in vivo and in vitro. DAVID(http://david.abcc.ncifcrf.gov) website showed that miR 138-5p/FOXO3a is a potential downstream target of circ DENND4C. Knock-down of circ DENND4C in HK-2 cells resulted in increased expression of miR 138-5p and increased miR 138-5p can reverse the regulation of FOXO3a. Dual-luciferase assay verified the reverse interaction between circ DENND4C, miR 138-5p, and FOXO3a. Exosomes promote cell proliferation and inhibit the activation of NLR family pyrin domain containing 3 through the circ DENND4C/miR 138-5p/FOXO3a pathway, thereby reducing pyroptosis and AKI. Circ DENND4C may be a potential therapeutic target for AKI. • USCs exosomes played a protective role in inhibiting pyroptosis and alleviating AKI both in vitro and in vivo. • The accumulation of exosomes in the affected kidney with I/R injury in vivo contributed to the repair of kidney injury. • The differential expression of various circRNAs during renal injury may be related to the mechanism of renal I/R injury. • Circ DENND4C enriched in USCs exosomes inhibited pyroptosis and alleviated AKI by regulating miR 138-5p/FOXO3a. • Circ DENND4C may be a new potential therapeutic target for AKI. [ABSTRACT FROM AUTHOR]

Identifying the most influential spreaders is an important issue in epidemic spreading, viral marketing, and controlling the spreading process of information. Thus, methods for identifying influential spreaders in complex networks have received increasing attention from researchers. During recent decades, researchers have proposed many methods. However, each of these methods has advantages and disadvantages. In this paper, we propose a new efficient algorithm for identifying influential spreaders based on the Dempster–Shafer (D–S) evidence theory, which is a complete theory that deal with uncertainty or imprecision. We call our proposed algorithm D-2SN, which trades off between the degree (D) and the 2-step neighbor information (2SN) of every node in a network. Specifically, the influence of both the degree and the 2SN of each node are represented by a basic probability assignment (BPA). D-2SN is determined by the fusion of these BPAs. Since the algorithm considers not only the topological structure of each node, but also its neighbors' structure, it is a good choice to balance cost and performance. In addition, it also exhibits very low time complexity O (⟨ k ⟩ n), which makes it applicable to large-scale networks. To evaluate the performance of D-2SN, we employ the Independent Cascade (IC) and Liner Threshold (LT) models to examine the spreading efficiency of each node and compare D-2SN with several classic methods in eight real-world networks. Extensive experiments demonstrate the superiority of D-2SN to other baseline methods. [ABSTRACT FROM AUTHOR]

The anisotropy of seismic velocities in the mantle, when integrated with high-resolution tomographic models and geologic information, can be used to detect active mantle flows in complex plate boundary areas, providing new insights on the impact of mantle processes on the topography of mountain belts. Here we use a densely spaced array of temporary broadband seismic stations to analyze the seismic anisotropy pattern of the western Alpine region, at the boundary between the Alpine and Apenninic slabs. Our results are supportive of a polyphase development of anisotropic mantle fabrics, possibly starting from the Jurassic to present. Geophysical data presented in this work, and geologic evidence taken from the literature, indicate that: (i) fossil fabrics formed during Tethyan rifting may be still preserved within the Alpine and Apenninic slabs; (ii) mantle deformation during Apenninic slab rollback is not compensated by a complete toroidal flow around the northern tip of the retreating slab; (iii) the previously observed continuous trend of anisotropy fast axes near-parallel to the western Alpine arc is confirmed. We observe that this arc-parallel trend of fast axes is located in correspondence to a low velocity anomaly in the European upper mantle, beneath regions of the Western and Ligurian Alps showing the highest uplift rates. We propose that the progressive rollback of the Apenninic slab, in the absence of a counterclockwise toroidal flow at its northern tip, induced a suction effect at the scale of the supraslab mantle. The resulting mantle flow pattern was characterized by an asthenospheric counterflow at the rear of the unbroken Western Alps slab and around its southern tip, and by an asthenospheric upwelling, mirrored by low P wave velocities, that would have favored the topographic uplift of the Alpine belt from the Mont Blanc to the Mediterranean sea. [ABSTRACT FROM AUTHOR]

In continental subduction zones, the behaviour of the mantle wedge during exhumation of (ultra)high-pressure [(U)HP] rocks provides a key to distinguish among competing exhumation mechanisms. However, in spite of the relevant implications for understanding orogenic evolution, a high-resolution image of the mantle wedge beneath the Western Alps is still lacking. In order to fill this gap, we perform a detailed analysis of the velocity structure of the Alpine belt beneath the Dora-Maira (U)HP dome, based on local earthquake tomography independently validated by receiver function analysis. Our results point to a composite structure of the mantle wedge above the subducted European lithosphere. We found that the Dora-Maira (U)HP dome lays directly above partly serpentinized peridotites (Vp ~ 7.5 km/s; Vp/Vs = 1.70–1.72), documented from ~ 10 km depth down to the top of the eclogitized lower crust of the European plate. These serpentinized peridotites, possibly formed by fluid release from the subducting European slab to the Alpine mantle wedge, are juxtaposed against dry mantle peridotites of the Adriatic upper plate along an active fault rooted in the lithospheric mantle. We propose that serpentinized mantle-wedge peridotites were exhumed at shallow crustal levels during late Eocene transtensional tectonics, also triggering the rapid exhumation of (U)HP rocks, and were subsequently indented under the Alpine metamorphic wedge in the early Oligocene. Our findings suggest that mantle-wedge exhumation may represent a major feature of the deep structure of exhumed continental subduction zones. The deep orogenic levels here imaged by seismic tomography may be exposed today in older (U)HP belts, where mantle-wedge serpentinites are commonly associated with coesite-bearing continental metamorphic rocks. [ABSTRACT FROM AUTHOR]

The Dabieshan massif is famous as a portion of the world's largest HP-UHP metamorphic belt in east-central China that was built by the Triassic North-South China collision. The central domain of the Dabieshan massif is occupied by a huge migmatite-cored dome [i.e., the central Dabieshan dome (CDD)]. Origin of this domal structure remains controversial. Synthesizing previous and our new structural and geochronological data, we define the Cretaceous Dabieshan as an orogen-scale metamorphic core complex (MCC) with a multistage history. Onset of lithospheric extension in the Dabieshan area occurred as early as the commencement of crustal anatexis at the earliest Cretaceous (ca. 145 Ma), which was followed by primary (early-stage) detachment during 142-130 Ma. The central Dabieshan complex in the footwall and surrounding detachment faults recorded a consistently top-to-the-NW shearing. It is thus inferred that the primary detachment was initiated from a flat-lying detachment zone at the middle crust level. Removal of the orogenic root by delamination at ca. 130 Ma came into the extensional climax, and subsequently isostatic rebound resulted in rapid doming. Along with exhumation of the footwall, the mid-crustal detachment zone had been warped as shear zones around the CDD. After 120 Ma, the detachment system probably experienced a migration accommodated to the crustal adjustment, which led to secondary (late-stage) detachment with localized ductile shearing at ca. 110 Ma. The migmatite-gneiss with HP/UHP relicts in the CDD (i.e., the central Dabieshan complex) was product of the Cretaceous crustal anatexis that consumed the deep-seated part of the HP-UHP slices and the underlying para-autochthonous basement. Compared with the contemporaneous MCCs widely developed along the eastern margin of the Eurasian continent, we proposed that occurrence of the Dabieshan MCC shares the same tectonic setting as the 'destruction of the North China craton'. However, geodynamic trigger of the Cretaceous continental-scale NW-SE extension in eastern Asia is still a mystery. [ABSTRACT FROM AUTHOR]

In order to analyze the corona discharge characteristics at the grounding object tip under the thundercloud electric field environment, scaled simulation test has been conducted on corona discharge in the plane-single/double earthed rods air gap. Five gap configurations with three different grounding rods were built during experiments. Factors as rod tip curvature, voltage and gap configuration have been considered in detail. Corona voltage, corona current and the number of ultraviolet photons were all recorded. The grounding rod tip curvature radius can affect corona discharge processes at grounding rod tip. With increasing applied negative DC voltage, five typical corona processes of dark discharge, burst streamer corona, periodic streamer corona, glow corona and brush discharge occurred at conical and spherical grounding rod tip (r = 0. 75 cm) , but under d = 5 cm and d = 10 cm no glow corona and brush corona appeared at spherical grounding rod tip (r = 1. 25 cm). It is much easier for grounding rod tip with smaller curvature to form glow corona phenomenon. The mean value I av of periodic streamer corona current pulse amplitude decreases with grounding rod tip curvature radius, while the mean corona current pulse width and pulse interval increases. For grounding rod with conical tip, there is little difference of average current pulse amplitude between periodic streamer corona and brush corona; for grounding rod with spherical tip (r = 0. 75 cm) , the mean value I av of brush corona pulse amplitude increases to 3595.8 μ A which has increased by a factor of about 36. The photon number at conical grounding rod tip is larger than that at spherical grounding rod tip at low voltage but the relation reverses as the applied voltage exceeds a critical value. The shielding effect of two grounding rods in plane-double rods air gaps increased with spherical grounding rod curvature radius and decreases with the lateral gap distance between two grounding rods. • Simulate the corona discharge characteristics at grounding rod tip under thunderstorm electric field. • Corona discharge experiments in plane-single rod/double rods air gaps are conducted. • The shielding effect of grounding rods are studied in different plane-double rods air gaps. [ABSTRACT FROM AUTHOR]

• Shielding effect of corona discharges on two grounding wires during thunderstorm. • Corona discharge on the grounding wire increases with wind speed during thunderstorm. • Corona discharge on the grounding wire is influenced by wind direction during thunderstorm. Many experiments simulate the corona phenomenon on the surface of single grounding wire of transmission line in an ideal environment, without considering the influence of environmental factors such as wind. In this paper, the finite element method is used to consider the motion process of small positive ions, large aerosol ions and aerosol neutral particles. Based on the simulation results, the shielding effect between two grounding wires can be seen by comparison. Considering the wind speed from 0 m/s to 5 m/s, the grounding wire corona discharge experiment was carried out. The simulation and experimental results show that with the increase of wind speed, the corona discharge degree on the surface of the grounding wire increases, the positive ion concentration generated by the corona increases, and the corona current increases. The positive ion offset increases, the shielding effect on the grounding wire weakens, and the electric field intensity above the grounding wire increases, which increases the probability of the corona to flow beam transition. With the increase of wind direction angle, the positive ion density on the grounding wire surface increases, which weakens the spatial electric field intensity and is not conducive to the development of upward leader. [ABSTRACT FROM AUTHOR]

The Longmenshan thrust belt (LMTB) is one of the best natural laboratories for thin-skinned tectonics and has developed a series of NE-SW trending fold-and-thrust structures represented by a series of nappes and klippes, exemplified by the Tangbazi and Bailuding klippe. However, the timing and emplacement mechanism of these klippes are still in dispute. Three possible mechanisms have been proposed: (1) a Mesozoic-Cenozoic southeastward thrusting, (2) a Cenozoic gravity gliding, and (3) glacial deposition. Almost all of these klippes are tectonic and overlaid on folded Late Triassic sandstone except the Tangbazi klippe, which is located in the center of the LMTB and has a narrow tail extending southeastward and covering Jurassic-Quaternary rocks. This geometric relationship is considered the most important stratigraphic evidence to support the post-Cenozoic emplacement of the Longmenshan klippe. Our structural and petrological observations show that the rocks at the front of the Tangbazi and Bailuding structures are brecciated limestone, which is assumed to have been generated by a gravitational collapse and is not characteristic of the massive Permian strata. Artemisia pollen, which has been exclusively recognized in post-Late Eocene strata in Central Asia, was found in the matrix of this brecciated limestone. Therefore, our discovery indicates that the brecciated limestone was deposited after the Late Eocene rather than during the Permian as annotated on the geological map. In contrast, unbrecciated, massive Permian limestone overlaid on the folded Late Triassic rocks. Hence, the anomalous relationship of Permian strata overlaying Late Triassic rocks cannot be evidence of Cenozoic emplacement. According to currently recognized bulk strata relationships, we can only be sure that the klippe was emplaced in the post Late Triassic. The petrological characteristics of the brecciated limestone show that it was crumbled before the re-sedimentation of the breccia, implying that the LMTB might have experienced a rapid uplift during the Late Eocene. [ABSTRACT FROM AUTHOR]

Highlights: [•] 40Ar/39Ar thermochronology of K-feldspar from Cretaceous granites in Yanshan Belt have recorded two rapid cooling events. [•] The first cooling phase was consistent with widespread extension in Yanshan belt and Eastern China. [•] The second cooling phase was in accordance with regional uplift in Yanshan Belt. [•] Rapid cooling events in Yanshan Belt were probably a shallow response to the destruction of the North China Craton. [Copyright &y& Elsevier]