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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]

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]

In this paper, a series of porous hierarchical Mg/Al layered double hydroxides (named as LDH, TTAC-MgAl-LDH, CTAC-MgAl-LDH, and OTAC-MgAl-LDH) was synthesized by a simple green hydrothermal method using wormlike micelles formed by salicylic acid and surfactants with different carbon chain lengths (0, 14, 16, and 18) as soft templates. BET, XRD, FTIR, TG, and SEM characterizations were carried out in order to investigate the structure and properties of the prepared materials. The results showed that the porous hierarchical CTAC-MgAl-LDH had a large specific surface area and multiple pore size distributions which could effectively increase the reaction area and allow better absorption capability. Benefiting from the unique architecture, CTAC-MgAl-LDH exhibited a large adsorption capacity for sulfonated lignite (231.70 mg/g) at 25 °C and a pH of 7, which outperformed the traditional LDH (86.05 mg/g), TTAC-MgAl-LDH (108.15 mg/g), and OTAC-MgAl-LDH (110.51 mg/g). The adsorption process of sulfonated lignite followed the pseudo-second-order kinetics model and conformed the Freundlich isotherm model with spontaneous heat absorption, which revealed that electrostatic adsorption and ion exchange were the main mechanisms of action for the adsorption. In addition, CTAC-MgAl-LDH showed a satisfactory long-time stability and its adsorption capacities were still as high as 198.64 mg/g after two adsorption cycles. [ABSTRACT FROM AUTHOR]

A biomimetic hierarchical membrane consisting of ZIF-8 and MXene with controllable morphology could be fabricated by the facile electrochemical deposition method, well-realizing Li+/Mg2+ sieving. This membrane could work stably in real brine with perm-selectivity of Li+/Mg2+ up to 47.4. [ABSTRACT FROM AUTHOR]

Coupling low-grade heat (LGH) with salinity gradient is an effective approach to increase the efficiency of the nanofluidic-membrane-based power generator. However, it is a challenge to fabricate membranes with high charge density that ensures ion permselectivity, while maintaining chemical and mechanical stability in this composite environment. Here, we develop a bis[2-(methacryloyloxy)ethyl] phosphate (BMAP) hydrogel membrane with good thermal stability and anti-swelling property through self-crosslinking of the selected monomer. By taking advantage of negative space charge and three-dimensional (3D) interconnected nanochannels, salinity gradient energy conversion efficiency is substantially enhanced by temperature difference. Theoretical and experimental results verify that LGH can largely weaken the concentration polarization, promoting transmembrane ion transport. As a result, such a hydrogel membrane delivers high-performance energy conversion with a power density of 11.53 W·m−2 under a negative temperature difference (NTD), showing a 193% increase compared with that without NTD. [ABSTRACT FROM AUTHOR]

In order to solve the problem of poor dispersion and stability of mixed metal hydroxide (MMH), a kind of mixed metal hydroxide-like compound (MMHlc) gel was synthesized for use as the base mud in drilling fluid instead of bentonite gel. Na2CO3, Na2SiO3, and C17H33CO2Na were used as precipitants to form MMHlc with larger interlayer spacing and smaller particle size. MMHlc was synthesized by the coprecipitation method at 25 °C with a metal molar ratio of Mg:Al:Fe = 3:1:1. The performance evaluation of the treated drilling fluid showed that MMHlc (S2) synthesized using Na2SiO3 as the precipitant had the characteristics of low viscosity, low filtration, and a high dynamic plastic ratio at 25 °C, which fully met the requirements of oil field application, and it maintained its excellent properties after being aged at 250 °C for 16 h. Linear expansion and rolling recovery experiments showed that the S2 sample had excellent rheological properties and good inhibition. X-ray diffraction and FT-IR experiments showed that S2 had the most complete crystal structure, its interlayer distance was large, and its ion exchange capacity was strong. The thermogravimetric experiment showed that the S2 crystal was stable and the temperature resistance of the crystal could reach 340 °C. Zeta potential, particle size analysis, SEM, and TEM results showed that S2 is a nanomaterial with a complete morphology and uniform distribution. The drilling fluid of this formula had the characteristics of low viscosity, low filtration loss, and a high dynamic plastic ratio, and it met the conditions for oil field application. Considering these results, the new MMH prepared by our research institute is a drilling fluid material that can be used at ultra-high temperatures and can provide important support for drilling ultra-deep wells. [ABSTRACT FROM AUTHOR]

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar‐toughened tungsten disulfide (WS2) composite membrane with bioinspired serosa‐mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m−2 under irradiation, outperforming traditional two‐dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti‐fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy. [ABSTRACT FROM AUTHOR]

Nanofluidic reverse electrodialysis provides an attractive way to harvest osmotic energy. However, most attention was paid to monotonous membrane structure optimization to promote selective ion transport, while the role of external fields and relevant mechanisms are rarely explored. Here, we demonstrate a Kevlar‐toughened tungsten disulfide (WS2) composite membrane with bioinspired serosa‐mimetic structures as an efficient osmotic energy generator coupling light. As a result, the output power could be up to 16.43 W m−2 under irradiation, outperforming traditional two‐dimensional (2D) membranes. Both the experiment and simulation uncover that the generated photothermal and photoelectronic effects could synergistically promote the confined ion transport process. In addition, this membrane also possesses great anti‐fouling properties, endowing its practical application. This work paves new avenues for sustainable power generation by coupling solar energy. [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]

Up to 20% of all business‐to‐consumer deliveries fail on the first attempt. Failed deliveries not only carry cost implications but also incur damage to retailers' brand reputation. Despite its economic significance, research has paid little attention to delivery attempt as an operational outcome or seldom accounted for its effects in routing models. This is partly due to the many factors that can influence delivery outcomes. We address this knowledge gap by first demonstrating that failed delivery attempts can be reasonably predicted using common routing, demand, environmental, and market attributes at both the individual package and route levels. For model‐building, we use transaction data from an e‐commerce retailer in South America. We then explore the value of accounting for failed delivery attempts in routing models. We propose a two‐stage greedy algorithm for solving large problem instances. Our analysis indicates that not accounting for the probability of failed attempts in routing models may create a significant downward bias in the total cost of delivery. The analysis also suggests that manipulating the sequence in which packages in a route are delivered can be a cost‐efficient lever that firms can employ at almost zero cost to profoundly affect delivery outcomes. We replicate the prediction model to a new sample from a delivery company in Singapore and calibrate it for a randomized field experiment to validate our algorithm's performance. Packages and drivers are randomly assigned to either our algorithm or the focal company's existing algorithm. Results suggest that our algorithm, on average, reduces the share of failed delivery attempts by 10% and the total cost of delivery by $13 per route. We further propose drivers' discretionary work effort and the goal‐gradient hypothesis as a mechanism for the efficacy of our algorithm. Controlling for time of day and other fixed effects, we empirically find that packages assigned to slots later in the route tend to have a lower failure rate because drivers display a higher degree of discretionary work effort toward the end of a route. Our approach can be applied to other firms' last‐mile delivery operations to improve their delivery execution. [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]

Polyacrylamide and its derivatives are commonly used as viscosity enhancers in water‐based drilling fluids, but they have limitations in terms of salt resistance and temperature resistance. In this study, a novel cationic functional monomer, 4‐allylaminocarbonyl‐1‐dodecylpyridinium bromide, was introduced into the molecular chains of an acrylamide and acrylic acid copolymer in order to improve its temperature resistance and salt tolerance. Results showed that the apparent viscosity of a 2000 mg/L copolymer solution was 440.4 mPa s at a shear rate of 7.34 s−1, decreasing to 23.5 mPa s at 510 s−1 before recovering to 49.2 mPa s when the shear rate returned to 170 s−1. After 16 h of aging at 120°C, a brine drilling fluid containing 1% of the copolymer showed an apparent viscosity retention rate of 70%, likely due to the formation of a stable net structure between the copolymer's molecular chains and clay particles. These results suggest that the copolymer could be an excellent candidate for use as a viscosity enhancer in drilling fluids. [ABSTRACT FROM AUTHOR]

We demonstrate a high-power Ho :YLF slab laser with two crystals inside a single resonator pumped by a Tm:YAP slab laser. At an incident pump power of 218 W, this device produces a maximum continuous-wave output power of 100 W at ∼2064 nm, with a slope efficiency and an optical conversion efficiency of 57.5% and 49.9%, respectively. Furthermore, we investigate the output performance for various output couplers with a fixed cavity length of 190 mm. At an output power of 60 W, the beam quality factor M2 is 85 in the x direction and 1.2 in the y direction. Moreover, we develop a theoretical model to analyze the temperature distribution in the Ho :YLF slab crystals. [ABSTRACT FROM AUTHOR]

Iron overloads osteoporosis mainly occurs to postmenopausal women and people requiring repeated blood transfusions. Iron overload increases the activity of osteoclasts and decreases the activity of osteoblasts, leading to the occurrence of osteoporosis. Conventional treatment options include calcium supplements and iron chelators. However, simple calcium supplementation is not effective, and it does not have a good therapeutic effect. Oxidative stress is one of the triggers for osteoporosis. Therefore, the study focuses on the antioxidant aspect of osteoporosis treatment. The present work revealed that antioxidant carboxymethyl chitosan-based carbon dots (AOCDs) can effectively treat iron overload osteoporosis. More interestingly, the functional modification of AOCDs by doping calcium gluconate (AOCDs:Ca) is superior to the use of any single component. AOCDs:Ca have the dual function of antioxidant and calcium supplement. AOCDs:Ca effectively improve the bioavailability of calcium and achieve ultra-low concentration calcium supplement for the treatment of iron-induced osteoporosis in zebrafish. [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]

Solid-free drilling fluid has more advantages as a new type of drilling fluid compared with traditional drilling fluid, such as improving drilling efficiency, protecting oil and not having clay particles clog the oil and gas layer. In this study, Zn/Cu/Fe-doped magnesium–aluminum hydroxide (Mg-Al MMH) was prepared using the co-precipitation method and evaluated in solid-free drilling fluid. The inhibition mechanism of synthesized hydroxide was analyzed by X-ray diffraction, laser particle-size analysis and thermogravimetric analysis. The samples were directly used as drilling fluid base muds for performance evaluation. The results showed that the linear expansion rate of 4% M6-Fe was only 12.32% at room temperature within 2 h, that the linear expansion rate was 20.28% at 90 °C and that the anti-swelling rate was 81.16% at room temperature, indicating that it has a strong inhibition ability at both room temperature and at high temperatures. Meanwhile, the possibility of multi-mixed metal hydroxide as a drilling fluid base mud is discussed in this study. We found that 4% M6-Fe exhibited low viscosity, a high YP/PV ratio and high temperature resistance, and its apparent viscosity retention rate reached 100% rolled at 200 °C for 16 h, with a YP/PV ratio of 2.33. [ABSTRACT FROM AUTHOR]

In this study, the foaming properties of a compound surfactant formula containing cetyltrimethylammonium chloride (CTAC), cocamidopropyl betaine (CDAB), fatty alcohol polyoxyethylene ether-7 (AEO7) and sodium alpha-olefin sulfonate (AOST) were evaluated to meet the application requirements for foam generation and foam drainage in gas wells. The results exhibited that the foaming volume and the half-life of the compound surfactant solution (0.05 wt % CTAC + 0.7 wt % CDAB + 0.6 wt % AEO7 + 0.05 wt % AOST) can reach the values of 550 mL and 23 min, respectively, which suggested that the foaming ability and stability were improved in comparison with each solution containing a single surfactant. It showed that the surface tension can be lowered to 22.4 mN/m with the presence of the compound surfactants. Simultaneously, the microstructure of the foam was observed using a polarizing microscope, and it was found that there were almost no polyhedron structures in the foam within a certain range of formula concentrations. The results of the experiments also clarify that the formula has well properties of temperature resistance and salt resistance (measured using a high-speed agitator). [ABSTRACT FROM AUTHOR]

In this paper, mixed metal hydroxide (MMH) was prepared via MgCl2 and AlCl3 by the co-precipitation method and characterized by XRD, TGA laser and particle size analysis. The inhibitory effect of MMH on the swelling of clay was evaluated by linear expansion, mud ball, laser particle size analysis, X-ray diffraction analysis and TGA. The linear expansion experiment showed that MMH with a ratio of Mg:Al = 3:1 displayed a strong inhibitory effect on bentonite expansion when 0.3% MMH was added to the drilling fluid, demonstrating better inhibition than 4.0% KCl. Within 48 h, only a few cracks were visible on the mud ball surface in the 0.3% MMH suspension, which indicates that MMH can inhibit wet bentonite for deep hydration. X-ray diffraction and particle size analyses of bentonite were conducted before and after MMH was added to illustrate the inhibition. MMH also displayed high temperature resistance in water-based drilling fluid as a shear strength-improving agent, and its dynamic plastic ratio and shear force were stable after aging at 200 °C for 16 h. [ABSTRACT FROM AUTHOR]

With the increasing amount of drilling of directional wells and large‐displacement wells, high torque and high resistance have become critical problems. Therefore, high‐performance and environment‐friendly lubricants for water‐based drilling fluid are urgently needed. In this paper, poly(ethylene glycol) 2000 (PEG) was used as a lubricant, and the lubricity, inhibition, compatibility and temperature resistance of the PEG lubricant were investigated. The results show that 0.1% (mass ratio) PEG in water‐based drilling fluid can reduce the friction coefficient of mud cake by 44.5%. This PEG also has certain inhibition and temperature resistance. As PEG is used with other drilling fluid additives, the compatibility was good and the lubricity of drilling fluid can be improved effectively. The lubricating mechanism of PEG was explored and the results showed that the hydrophobic alkane chains in the PEG molecules were adsorbed on the surface of bentonite, forming a hydrophobic film on the friction surface, thereby forming a lubricating layer. Field application in Sulige Gas Field showed that the PEG lubricant has good lubricity and can meet the technical requirements of corresponding horizontal wells. © 2020 Society of Industrial Chemistry [ABSTRACT FROM AUTHOR]

Background: With the implementation of Antimicrobial Stewardship Program, clinical pharmacists' consultation (CPC) for infectious diseases (ID) is gradually adopted by many hospitals in China. We conducted a cohort study to evaluate the effectiveness of CPC in ID treatment on patient outcomes and potential determinants. Methods: Based on a registry database, a prospective cohort study was conducted in Guizhou Provincial People's Hospital. The main exposure factor was whether clinician adopted the suggestion from clinical pharmacist. The outcome was effective response rate (ERR) of ID patients. The variables associated with the outcome (e.g., age, gender, severity of infection, liver function, and kidney function) were also prospectively recorded. A multilevel model was performed to analyze the factors related to ERR. Results: A total of 733 ID inpatients were included in the final analysis according to the predesigned inclusion and exclusion criteria. The proportion of clinical pharmacists' suggestions adopted by clinicians and ERR were 88.13 and 69.03%, respectively. Significant data aggregation (P < 0.05) for individuals at the level of department was observed. According to the two-level variance component model, liver dysfunction (Adjusted Odds Ratio (AOR) = 0.649, 95% Credible Interval (CI) : 0.432–0.976), severity of infection (AOR = 0.602, 95% CI : 0.464–0.781), and adopting the suggestion from pharmacist (AOR = 1.738, 95% CI : 1.028–2.940) had significant association with ERR. Conclusion: Our study suggests that the effect of CPC on ID treatment is significant. The policy/decision makers or hospital managers should be cognizant of the critical value of clinical pharmacists in ID treatment. [ABSTRACT FROM AUTHOR]

Objective: We expected to demonstrate a practical framework for oral squamous cell carcinoma (OSCC) candidate biomarker analysis at the pathway level based on the attract method, so as to give great insights to reveal the pathological mechanism underlying this disease at its early stage.Methods: First, gene expression profile of OSCC was recruited and preprocessed. Then, Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis was conducted. Next, attract method, an approach that begins its analysis from the "foundation knowledge sets" to discriminate the cell-phenotypes by those well-annotated gene-sets, then expands the syn-expression groups via decomposing each significant pathway into correlated subsets and extends the analysis to the entire expression was applied to identify core pathways. Finally, gene ontology (GO) functional enrichment analysis was performed on each of the correlated set groups to discover any potentially shared biological themes.Results: A total of 226 pathways were obtained. Then, 39 core KEGG pathways was identified via attract. After removing the uninformative genes, a total of 1, 2, and 3 clusters were separately identified for the three discriminative pathways extracellular matrix (ECM)-receptor interaction, neuroactive ligand-receptor interaction, and cell adhesion molecules (CAMs) pathway based on the correlation coefficient < 0.85. GO functional enrichment analysis for the correlated partners groups indicated that there were 40, 11, 78 significant GO terms for ECM-receptor interaction, neuroactive ligand-receptor interaction, and CAMs pathway, respectively.Conclusions: We predict that pathways such as ECM-receptor interaction, neuroactive ligand-receptor interaction, and CAMs may play significant roles in OSCC and targeting these pathways may provide an effective avenue to combat the complicated illness. [ABSTRACT FROM AUTHOR]

Abstract: This work first presents field structural analysis, anisotropy of magnetic susceptibility (AMS) measurements, and kinematic and microstructural studies on the Neoproterozoic Pengguan complex located in the middle segment of the Longmenshan thrust belt (LMTB), NE Tibet. These investigations indicate that the Pengguan complex is a heterogeneous unit with a ductilely deformed NW domain and an undeformed SE domain, rather than a single homogeneous body as previously thought. The NW part of the Pengguan complex is constrained by top‐to‐the‐NW shearing along its NW boundary and top‐to‐the‐SE shearing along its SE boundary, where it imbricates and overrides the SE domain. Two orogen‐perpendicular gravity models not only support the imbricated shape of the Pengguan complex but also reveal an imbrication of high‐density material hidden below the Paleozoic rocks on the west of the LMTB. Regionally, this suggests a basement‐slice‐imbricated structure that developed along the margin of the Yangtze Block, as shown by the regional gravity anomaly map, together with the published nearby seismic profile and the distribution of orogen‐parallel Neoproterozoic complexes. Integrating the previously published ages of the NW normal faulting and of the SE directed thrusting, the locally fast exhumation rate, and the lithological characteristics of the sediments in the LMTB front, we interpret the basement‐slice‐imbricated structure as the result of southeastward thrusting of the basement slices during the Late Jurassic‐Early Cretaceous. This architecture makes a significant contribution to the crustal thickening of the LMTB during the Mesozoic, and therefore, the Cenozoic thickening of the Longmenshan belt might be less important than often suggested. [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]

Detrital zircons from Cretaceous micaschist, late Eocene-earliest Oligocene sandstone and early Oligocene siltstone of the Western Alps fall into three main separable age clusters at 610-540 Ma, 490-430 Ma, and 340-280 Ma that correspond to the Cadomian (Neoproterozoic), Ordovician, and Variscan (Carboniferous) events widespread in western and central Europe. Hf isotopic results indicate that these three magmatic and tectonic episodes did not give rise to significant production of juvenile crust. A distinguishable group of Triassic zircons, around 250-200 Ma which is considered to derive from the Southern Alps, has been detected in the early Oligocene 'Schistes à Blocs' formation and the Briançonnais 'Flysch Noir'. In contrast, this age group is absent in late Eocene to earliest Oligocene sandstones. In agreement with sedimentological studies, our results show that the main source areas of the Eocene sandstone were probably located in the European continent. The arrival of detritus from the Internal Zone occurred in early Oligocene, coeval with the tectonic rotation from northwestward to westward in the propagation of allochthonous units. Based on previous studies and our new data, we argue that the Briançonnais Zone was likely a paleorelief since the middle Eocene that accounts for the lack of detritus from the Adriatic units. Contemporary sediments were accumulated in the foredeep of the Adriatic plate. From Oligocene time onward, the blockage was cut through after a regional uplifting, and thus, the Internal Zone started to provide detritus into the western flexural basins. [ABSTRACT FROM AUTHOR]

Erratum [ABSTRACT FROM AUTHOR]

The Penglaitan section, as the Global Stratotype Section for the Guadalupian-Lopingian boundary (GLB), displays continuous deposition with a complete succession of pelagic conodont zones across the GLB. However, there is no reliable radiometric age from the Penglaitan section itself to constrain the GLB. Here, we report SIMS zircon U-Pb ages from two bentonite layers (Bed 7c) in the Penglaitan Global Stratotype Section near the GLB. The sample PL-62-1 yields a weighted mean 238U/206Pb age of 257.1 ± 2.2 Ma, and the sample PL-62-2 yields a weighted mean 206Pb/238U age of 257.0 ± 4.2 Ma. Therefore, we consider 257.0-257.1Ma as the age of deposition of Bed 7c (the end of the C. postbitteri postbitteri conodont Zone, ca. 86 cm above the GLB), and, considering the depositional rate of chert, we suggest 258.6Ma as the age of the GLB. [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]

From the Middle to Late Permian, the Laibin area in Guangxi, South China, was situated on the slope of an isolated carbonate platform, on which continuous marine successions were deposited. Two global stratotype sections for the boundary between the Guadalupian (Middle Permian) and Lopingian (Late Permian) are located at Penglaitan and Tieqiao in the Laibin area, respectively, and thus are chosen for study. At the two locations, 14 facies are recognized in the Maokou and Heshan Formations, and they are further grouped into four facies associations (basin, lower slope, upper slope, and platform margin). Six main transgressive-regressive (TR) sequences are identified in strata from the Roadian (Middle Permian) to the Wuchiapingian (Late Permian). They are conformable marine sequences that were little influenced by regional uplift (Dongwu Movement) and so provide a good record of the sea-level changes in South China at this time. Based on the significant taxonomic selection and controversial marine faunal loss in the end-Guadalupian mass extinction, and the Middle-Late Permian sea-level changes recorded by the TR sequences in the Laibin area, it is suggested that this extinction event might have been triggered by the reduction and loss of shallow-marine habitat area caused by the end-Guadalupian regression. The global cooling and Emeishan volcanism also occurring at this time could have further enhanced this extinction event. [ABSTRACT FROM AUTHOR]

Major, trace and rare earth elements were measured in 27 samples of the Middle to Late Permian limestones from the Tieqiao section located on the marginal zone of an isolated platform (Laibin, South China). Shale-normalized REE+Y patterns of all samples show notably negative Ce anomalies (0.21-0.66, average 0.33), slightly positive Gd anomalies (1.08-1.30, average 1.20), and positive Y anomalies with superchondritic Y/Ho ratios (36-91, average 55), which are consistent with those of modern shallow seawater. Their relative LREEs enrichment with higher Nd/Yb ratios (0.58-1.80) than those of modern shallow seawater (0.21-0.50) suggests complicated sources of REEs for all samples. Compared with geochemical features of sediments influenced by terrigenous particles and hydrothermal fluids, it is concluded that ambient shallow seawater was the primary source of REEs in these limestones. Comparing the indicators of REE+Y elements (ΣREE, Nd/Yb, Ce/Ce*, Gd/Gd*, Eu/Eu* and Y/Ho) in limestones with those in bedded cherts from the Tieqiao section, we consider that limestone and bedded chert have similar sources of REE+Y elements: ambient shallow seawater with more or less hydrothermal fluids. In addition, there is a completely negative correlation between CaCO and SiO contents in limestones and bedded cherts. These results imply that precipitation of CaCO was inhibited by that of SiO which was derived mainly from hydrothermal fluid, especially in bedded cherts from the Tieqiao section. [ABSTRACT FROM AUTHOR]

In orogenic belts, a basal décollement zone often develops at depth to accommodate the shortening due to folding and thrusting of the sedimentary cover. In the Early Mesozoic intracontinental Xuefengshan Belt of South China, such a décollement zone is exposed in the core of anticlines formed by the emplacement of the late-orogenic granitic plutons. Our detailed, multi-scale structural analysis documents a synmetamorphic ductile deformation. In the basal décollement, the Neoproterozoic pelite and sandstone, and the intruding Early Paleozoic granites were deformed and metamorphosed into mylonites and orthogneiss, respectively. The metamorphic foliation contains a NW-SE stretching lineation associated with top-to-the-NW kinematic indicators. The ductile shearing of these high-strained rocks can be correlated with NW-verging folds and thrusts recognized in the Neoproterozoic to Early Triassic sedimentary cover. Monazite U-Th-Pb chemical dating, and zircon SIMS U-Pb dating provide age constraints of the ductile shearing between 243 and 226 Ma, and late-orogenic granite emplacement around 235-215 Ma. In agreement with recent geochronological data, these new results show that the Xuefengshan Belt is an Early Mesozoic orogen dominated by the NW-directed shearing and thrusting. At the southeastern boundary of the Xuefengshan Belt, the Chenzhou-Linwu fault separates the Early Mesozoic domain to the NW from the Early Paleozoic domain to the SE. The tectonic architecture of this belt was possibly originated from the continental underthrusting to the SE of the South China block in response to northwest-directed subduction of the Paleo-Pacific plate. [ABSTRACT FROM AUTHOR]

The Ediacaran-Cambrian transition was one of the most critical intervals in Earth history. During this interval, widespread chert was precipitated, commonly as a stratal wedge in carbonates, along the southern margin of the Yangtze Platform, South China. The chert wedge passes into a full chert succession further basinward to the south-east. Four lithotypes of chert are identified across the marginal zone in western Hunan: mounded, vein, brecciated and bedded chert. The mounded chert is characterized by irregular to digitiform internal fabrics, generally with abundant original vesicles and/or channels that mostly are lined by botryoidal chalcedony cements with minor quartz and barite crystals. The host chert (or matrix) of these mounds is dominated by amorphous cryptocrystalline silica, commonly disseminated with pyrite. The vein chert, with minor quartz locally, generally cross-cuts the overlying dolostone and chert horizons and terminates under the mounded and/or bedded chert bodies. The brecciated chert commonly occurs as splayed 'intrusions' or funnel-shaped wedges and cross-cuts the topmost dolostones. The bedded chert, the most common type, generally is thin to medium-bedded and laminated locally; it is composed of amorphous silica with minor amounts of black lumps. Microthermometry of fluid inclusions from vein and void-lining minerals (mainly quartz and barite) revealed homogenization temperatures from 120 to 180°C for the trapped primary fluids. Compositionally, these chert deposits generally are pure, with SiO2 > 92 wt%, and only minor Fe2O3 and Al2O3 contents, most of which show positive Europium anomalies in rare earth element patterns, especially for the mounded chert. All these data suggest that the marginal zone chert deposits resulted from a low-temperature, silica-rich hydrothermal system, in which the mounded chert was precipitated around the releasing vents, i.e. as silica chimneys. The vein and splayed brecciated chert, however, was formed along the syndepositional fault/fracture conduits that linked downward, while the bedded chert was precipitated in the quieter water column from the fallout of hydrothermal plumes onto the sea floor. These petrological and geochemical data provide compelling evidence and a new clue to the understanding of the extensive silica precipitation; rapid tectono-depositional and oceanic changes during the Ediacaran-Cambrian transition in South China. [ABSTRACT FROM AUTHOR]

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]