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Arteriovenous fistula (AVF) is currently the preferred vascular access for hemodialysis patients. However, the low maturation rate of AVF severely affects its use in patients. A more comprehensive understanding and study of the mechanisms of AVF maturation is urgently needed. In this study, we downloaded the publicly available datasets (GSE119296 and GSE220796) from the Gene Expression Omnibus (GEO) and merged them for subsequent analysis. We screened 84 differentially expressed genes (DEGs) and performed the functional enrichment analysis. Next, we integrated the results obtained from the degree algorithm provided by the Cytohubba plug-in, Molecular complex detection (MCODE) plug-in, weighted gene correlation network analysis (WGCNA), and Least absolute shrinkage and selection operator (LASSO) logistic regression. This integration allowed us to identify CTSG as a hub gene associated with AVF maturation. Through the literature search and Pearson's correlation analysis, the genes matrix metalloproteinase 2 (MMP2) and MMP9 were identified as potential downstream effectors of CTSG. We then collected three immature clinical AVF vein samples and three mature samples and validated the expression of CTSG using immunohistochemistry (IHC) and double-immunofluorescence staining. The IHC results demonstrated a significant decrease in CTSG expression levels in the immature AVF vein samples compared to the mature samples. The results of double-immunofluorescence staining revealed that CTSG was expressed in both the intima and media of AVF veins. Moreover, the expression of CTSG in vascular smooth muscle cells (VSMCs) was significantly higher in the mature samples compared to the immature samples. The results of Masson's trichrome and collagen I IHC staining demonstrated a higher extent of collagen deposition in the media of immature AVF veins compared to the mature. By constructing an in vitro CTSG overexpression model in VSMCs, we found that CTSG upregulated the expression of MMP2 and MMP9 while downregulating the expression of collagen I and collagen III. Furthermore, CTSG was found to inhibit VSMC migration. CTSG may promote AVF maturation by stimulating the secretion of MMP2 and MMP9 from VSMCs and reducing the extent of medial fibrosis in AVF veins by inhibiting the secretion of collagen I and collagen III. [ABSTRACT FROM AUTHOR]

Background and Aim: Fexuprazan is a novel potassium‐competitive acid blocker (P‐CAB). This study aimed to explore the noninferior efficacy and safety of fexuprazan to esomeprazole in treating erosive esophagitis (EE). Methods: This was a phase III, randomized, double‐blind multicenter study. Patients with endoscopically confirmed EE were randomized to receive fexuprazan 40 mg or esomeprazole 40 mg once a daily for 4–8 weeks. The healing rates of EE, symptom response, GERD‐health‐related quality life (GERD‐HRQL), and treatment‐emergent adverse events (TEAEs) were compared between fexuprazan group and esomeprazole group. Results: A total of 332 subjects were included in full analysis set (FAS) and 311 in per‐protocol set (PPS). The healing rates of fexuprazan and esomeprazole groups at 8 weeks were 88.5% (146/165) and 89.0% (145/163), respectively, in FAS and 97.3% (145/149) and 97.9% (143/146), respectively, in PPS. Noninferiority of fexuprazan compared with esomeprazole according to EE healing rates at 8 weeks was demonstrated in both FAS and PPS analysis. No significant difference was found between groups in EE healing rates at 4 weeks, symptom responses, and changes of GERD‐HRQL. The incidence of drug‐related AEs was 19.4% (32/165) in fexuprazan arm and 19.6% (32/163) in esomeprazole arm. Conclusion: This study demonstrated noninferior efficacy of fexuprazan to esomeprazole in treating EE. The incidence of TEAEs was similar between fexuprazan and esomeprazole. Trial registration number NCT05813561. [ABSTRACT FROM AUTHOR]

The Sand River area is in the northeastern part of the Central Zone (CZ) of the Limpopo Belt, and represents a key terrane to reveal early Precambrian tectonic processes in southern Africa. Based on petrology, U–Pb zircon ages, and major and trace element data of high-pressure (HP) mafic granulites from the Sand River area, the tectonic evolution of the Central Zone of the Limpopo Belt is re-evaluated here that allows revision of previous interpretations. The protoliths of the HP mafic granulites and amphibolites are sub-alkaline tholeiitic basalts similar to those formed at a mid-ocean ridge and intruded at 2.8 Ga. Based on the distinct mineral assemblages, three metamorphic stages (M1–M3) are recognized in the studied samples: (1) a peak HP granulite facies stage M1 (~1.17–1.32 GPa/~825–870°C), (2) a post-peak near-isothermal decompression stage M2 (~0.70–0.73 GPa/~835–880°C), and (3) a later, independent metamorphic stage M3 (~0.53–0.69 GPa/~793–801°C). M1 and M2 define together a clockwise P–T path. It reveals important information related to the Neoarchean collisional orogeny, and its later overprinted by an independent orogeny with subsequent exhumation and cooling. U–Pb zircon dating of two mafic granulites samples yielded protolith formation of the mafic granulites is prior to ~2.72 Ga, and the two metamorphic age peaks of ~2.72 (M1) and ~2.0 Ga (M3), which present the peak and post-peak cooling stages, respectively. The metamorphic evolution of HP mafic granulites in the Sand River area as reconstructed in this study suggests the Neoarchean collision of the Kaapvaal and Zimbabwe cratons and a discrete Paleoproterozoic orogenic overprint followed by post-orogenic exhumation and cooling. [ABSTRACT FROM AUTHOR]

Granulite facies rocks provide important keys to evaluating collisional metamorphism in orogenic belts. The mafic granulites of Baoding in the Fuping Complex of the North China Craton occur within the Trans-North China Orogen (TNCO), a major Paleoproterozoic collisional orogen. Here, we present results from detailed investigations on newly discovered garnet pyroxenite, garnet two-pyroxene granulite, and garnet-bearing-plagioclase amphibolite using petrographic, mineralogical, geochemical, and zircon U-Pb dating methods. Our results show that the Fuping Complex metamorphic evolution in this study evolved in four stages: prograde (M1), high-pressure granulite facies (M2), granulite facies (M3), and retrograde (M4) stages. The mineral assemblage of the prograde stage (M1) consists of Amp + Pl + Q within garnet cores. The mineral assemblage of high-pressure granulite facies at the peak stage (M2) consists of Gt + Cpx + Pl + Q ± Amp, forming the garnet pyroxenite. The granulite facies stage M3 is characterized by the occurrence of orthopyroxene, with a mineral assemblage of Gt + Cpx + Opx + Amp+ Pl + Q. The early retrograde stage M4-1 includes clinopyroxenes scattered inside amphiboles, following the breakdown of garnet and clinopyroxene. The mineral assemblage of this stage comprises Amp + Pl + Q + Ilm ± Cpx. Later, in the late retrograde stage M4-2, the composition of amphiboles changed to actinolite, and epidote and chlorite started to appear in the matrix. Traditional geothermobarometry yielded P-T conditions of 700~706 °C and 6.0~6.2 kbar for prograde stage M1, 854~920 °C and 13.0~13.8 kbar for high-pressure granulite facies stage M2, 912~939 °C and 8.1~9.9 kbar for M3, 661~784 °C and 3.1~4.4 kbar for M4-1, and 637~638 °C, 1.1~1.3 kbar for M4-2, along a clockwise P-T path with a nearly isothermal decompression (ITD) and slight heating. Zircon LA-ICP-MS U-Pb dating constrains the timing of the high-pressure granulite facies metamorphic event to be between 1.83 and 1.86 Ga. Geochemical features suggest that the protoliths of the high-pressure granulites may have formed in an island arc environment within a convergent margin setting. Together with results from previous studies, our data suggest that the ~1.85 Ga metamorphic age recorded in the Fuping Complex represents a regional metamorphism in the TNCO, associated with the subduction–collision and assembly of the Eastern and Western Blocks of the NCC. [ABSTRACT FROM AUTHOR]

To ascertain the Early-to-Middle Jurassic tectonic setting in the central Great Xing'an Range, this study investigated the Early and Middle Jurassic granitoids exposed in the Chaihe area in the central Great Xing'an Range based on isotopic chronology and petrogeochemistry. The results of this study show that the Early and Middle Jurassic granitoids have emplacement ages of 179–172 Ma. Moreover, the Early and Middle Jurassic granitoids are high-K calc-alkaline unfractionated I-type granitoids and high-K calc-alkaline fractionated I-type granitoids, respectively. The magma sources of the Early and Middle Jurassic granitoids both originated from the partial melting of newly accreted lower crustal basaltic rocks. Meanwhile, the Middle Jurassic magma sources were mixed with mantle-derived materials or ocean-floor sediments formed by the dehydration and metasomatism of subducted slabs. The Early and Middle Jurassic granitoids in the study area were formed in the subduction environment of the oceanic crust, in which the Mongol-Okhotsk oceanic plate was subducted southward beneath the Eerguna and Xing'an blocks. Moreover, the Siberian plate began to collide and converge with northeast China during the Middle Jurassic. [ABSTRACT FROM AUTHOR]

The Jiao-Liao-Ji Belt (JLJB) is the most representative Paleoproterozoic orogenic belt in the North China Craton (NCC). The sedimentation, metamorphism and magmatism of the Ji'an Group and associated granites provide significant insights into the tectonic evolution of the JLJB. In this study, we have synthesized published geochemistry and geochronology data on metasedimentary, metavolcanic and igneous rocks. According to the available data, the protoliths of the metasedimentary rocks are sets of shale, wacke, arkose, quartz sandstone and carbonate, while the protoliths of the metavolcanic rocks are calc-alkaline basalt, basaltic andesite, andesite, dacite and rhyolite. The rock assemblages indicate a transformation of the tectonic environment from a passive margin to an active continental margin following the onset of plate convergence and subduction. The A2-type gneissic granite (Qianzhuogou pluton) is formed in a subsequent back-arc basin extension setting at 2.20–2.14 Ga. The Ji'an Group was finally deposited in an active continental margin during the closure of a back-arc basin at 2.14–2.0 Ga. Then, the sediments were involved in a continent–arc–continent collision between the Longgang and Nangrim blocks at ~1.95 Ga. This process was accompanied by HP granulite-facies metamorphism at ~1.90 Ga. The subsequent exhumation and regional extension resulted in decompression melting during 1.90–1.86 Ga, producing metamorphism with an isothermal decompression clockwise P–T path. The resulting metapelites are characterized by perthite + sillimanite, and mafic granulites are characterized by orthopyroxene + clinopyroxene. The S-type porphyritic granite (Shuangcha pluton) is formed during the crustal anatexis. Meanwhile, extensive anatexis produced significant heating and triggered prograde to peak metamorphism with an anticlockwise P–T path. Cordierite-bearing symplectites around the garnet in the metapelites indicate a superposed isobaric cooling metamorphism. The ages of monazites and anatectic zircons suggest that the post-exhumation cooling occurred at 1.86–1.80 Ga. The Paleoproterozoic magmatism, sedimentation and metamorphism suggest a process of subduction back-arc basin extension and closure, collision and exhumation for the tectonic evolution of the JLJB. [ABSTRACT FROM AUTHOR]

The tectonic setting of the Jiamusi–Khanka Massif in the eastern sector of the Central Asian Orogenic Belt (CAOB) in NE China is still highly controversial. This review considers all existing data to evaluate the origin of the Jiamusi–Khanka Massif. The Precambrian basement in the Jiamusi–Khanka Massif is dominated by the Neoproterozoic orthogneisses (898–891 and 757–751 Ma), the Mashan Complex (peak metamorphism at 530–500 Ma), and syntectonically deformed early Palaeozoic granitoids (530–484 Ma) related to the metamorphism of the Mashan Complex. The Mashan Complex reveals a clockwise orogen-style P–T path with peak conditions of 850–870°C/8–9 kbar followed by isothermal decompression. It was intruded by syn- (530–500 Ma) and post-tectonic (490–476 Ma) granitic rocks. The Jiamusi–Khanka Massif cannot be directly derived from the North China, South China, or Tarim cratons. Instead, it may have originated in the Siberian Craton and formed once part of the Altai-Sayan and Baikal orogens at ~500 Ma. For the Jiamusi Massif, we developed a plate tectonic model, and relate the final granulite facies metamorphism to slab break-off after consumption of a branch of the Palaeo-Asian Ocean. [ABSTRACT FROM AUTHOR]

The inhibitory effects of vitamin D on colitis have been previously documented. Global vitamin D receptor (VDR) deletion exaggerates colitis, but the relative anticolitic contribution of epithelial and nonepithelial VDR signaling is unknown. Here, we showed that colonic epithelial VDR expression was substantially reduced in patients with Crohn's disease or ulcerative colitis. Moreover, targeted expression of human VDR (hVDR) in intestinal epithelial cells (IECs) protected mice from developing colitis. In experimental colitis models induced by 2,4,6-trinitrobenzenesulfonic acid, dextran sulfate sodium, or CD[4.sup.+]CD45R[B.sup.hi] T cell transfer, transgenic mice expressing hVDR in IECs were highly resistant to colitis, as manifested by marked reductions in clinical colitis scores, colonic histological damage, and colonic inflammation compared with WT mice. Reconstitution of Vdr-deficient IECs with the hVDR transgene completely rescued Vdr-null mice from severe colitis and death, even though the mice still maintained a hyperresponsive Vdr-deficient immune system. Mechanistically, VDR signaling attenuated PUMA induction in IECs by blocking NF-kB activation, leading to a reduction in IEC apoptosis. Together, these results demonstrate that gut epithelial VDR signaling inhibits colitis by protecting the mucosal epithelial barrier, and this anticolitic activity is independent of nonepithelial immune VDR actions., 10.1172/JCI65842. Introduction Ulcerative colitis (UC) and Crohn's disease (CD) are major chronic inflammatory bowel diseases (IBDs) in humans. Although the etiology and pathogenesis of IBD remain uncertain, it is believed [...]

The Heilongjiang Complex records the evolution history of the Mudanjiang Ocean, which is of great significance to constrain the amalgamation process of the Jiamusi and Songnen‐Zhangguangcai Range massifs. We carried out petrological, chronological, geochemical, mineral chemical and electron backscatter diffraction (EBSD) fabric analyses on the Heilongjiang Complex in the Yilan area. The latest zircon U–Pb dating results show that the protolith ages of the amphibolite are 261.3 ± 3.0 Ma and 261.8 ± 3.3 Ma, while that of the granodioritic mylonite is 207.8 ± 2.2 Ma. The amphibolites and granodioritic mylonite are enriched in large‐ion lithophile elements (e.g., Rb, Ba, and Sr) and light rare earth elements, with depletion in high‐field‐ strength elements (e.g., Nb, Ta, Zr, and Hf), indicating that the formation of the protoliths of the amphibolites and granodioritic mylonite is related to the subduction of the Mudanjiang oceanic plate under the Songnen‐Zhangguangcai Range Massif. The amphibolites and granodioritic mylonite both experienced two periods of metamorphic and deformation events. The metamorphic degree of the early period of metamorphism is low amphibolite facies, which records a clockwise P–T path from early increased temperature and pressure to a late isothermal depressurization. The P–T path reveals that this period of metamorphism is associated with the collision between two massifs. The later period of metamorphism reaches low greenschist facies, accompanied by deformation, which may be related to the rapid exhumation of the Heilongjiang Complex. This study provides a new perspective for exploring the collision and collage process of the Jiamusi and Songnen‐Zhangguangcai Range massifs. [ABSTRACT FROM AUTHOR]

The Mashan Complex of the Jiamusi Massif was traditionally considered as the oldest stratigraphic sequence in eastern NE China. However, the metamorphic degree of the Mashan Complex is different in different areas, which can be divided into Jixi–Mishan–Hulin granulite facies belt and Luobei–Huanan–Mudanjiang amphibolite facies belt. Here, we investigated the Mashan Complex in the Yilan area and present lots of new petrological, mineral chemical, geochemical, and U–Pb geochronological data, in addition to phase equilibria modelling, to constrain the timing of metamorphism, P–T conditions, and the P–T path of the Mashan Complex, and furthermore to deduce the crustal evolution of the Jiamusi Massif. The protoliths of the Mashan Complex in the Yilan area are greywackes and felsic sandstones, whose provenance is dominantly felsic rocks formed from a continental island arc. Petrographic observations, traditional thermobarometry, and quantitative phase equilibria modelling of the studied samples reveal P–T conditions from M2 to M3 of ~7.2 kbar/760–800°C and 4.5–5.0 kbar/585–610°C, respectively, which together define a clockwise P–T path involving decompressional cooling (M3) that followed the peak granulite‐facies metamorphism (M2). It reveals essential information related to the collision orogeny and post‐collision process. Zircon U–Pb dating of two felsic rocks yielded the peak of the granulite‐facies metamorphism in the Yilan area of the Jiamusi Massif that might have occurred at ~500 Ma. The overall deposition of the metamorphic rocks was later than ~760 Ma and that most of the detrital materials came from late Mesoproterozoic and early Neoproterozoic source rocks. [ABSTRACT FROM AUTHOR]

As the shield section passes through the silt-rock strata, the rock stratum of the tunnel section has to be blasted into blocks in advance, and the diameter of the blocks should be less than 30 cm after breaking, and then, the blocks could smoothly enter the soil cabin through the opening of the tunnel boring machine (TBM) cutter head and finally be discharged through the screw machine. The geology of rock blasting in silt-rock strata is complex, and the vibrations caused by blasting threaten the safety of buildings around the blasting area. According to the measured data of blasting vibrations at the sites, the waveform duration of vibration acceleration and the distribution characteristics of dominant frequency of vibration velocity were analyzed, the energy characteristics of vibration velocity were researched by wavelet analysis, and the attenuation laws of vibration velocity were studied by dimensional analysis (DA). The dominant frequency bands of vibration energy of ground are in the range of 0–15.625 Hz, and the distribution characteristics of frequency bands of vibration energy in different directions of the ground are similar to each other, but the energy magnitude is different from each other. The research results could provide a reference for the safe blasting distance of buildings under similar geological conditions. [ABSTRACT FROM AUTHOR]

This article presents new zircon U–Pb ages, data on whole‐rock major and trace elements for the Early Ordovician to Early Cretaceous granitic rocks exposed in the Mohe Basin of North‐east China, and reveals the tectonic evolution history of the Mohe area during this period. The zircon U–Pb dating results indicate that the magmatic activities from the Early Ordovician to Early Cretaceous in the Mohe area can be divided into six stages, which are ~473, ~281, ~247, ~215, ~130, and ~124 Ma, respectively. The granitic rocks mainly originated by partial melting of a depleted and heterogeneous lower crust, except for the quartz diorites at ~130 Ma, derived from the separated crystallization of mantle‐derived subalkaline basaltic magma. The rock associations and their geochemical features indicate that the granitic rocks of ~247 and ~215 Ma formed in an active continental margin setting, whereas the granitic rocks with formation ages of ~473, ~281, ~130, and ~124 Ma were formed in an extensional tectonic setting. Each stage of magmatic activity is consistent with the magmatism and tectonism of the Erguna Block. Based on the achievements of the previous studies, we put forward a comprehensive tectonic evolution of the Mohe area. From Early Ordovician to Late Permian (473 ~ 252 Ma), the Mohe area was influenced by the Palaeo‐Asian Ocean tectonic domain. Magmatism of Late Permian to Late Jurassic (247 ~ 155 Ma) is mainly due to the subduction of the Mongol–Okhotsk Ocean. During the Late Jurassic, the Erguna Block collided with the Siberian Craton and the southern margin of the Siberian Craton was uplifted and started furnishing sediments into the Mohe Basin. In the Early Cretaceous (~130 Ma), the Mohe area may have been controlled by the Palaeo‐Pacific Ocean and the Mongol–Okhotsk Ocean tectonic domains. [ABSTRACT FROM AUTHOR]

The Mohe Basin, to the south of Mongol–Okhotsk suture belt (MOSB) closely, is a good window into investigations of the evolution of the Mongol–Okhotsk Ocean during the Late Mesozoic. Sandstone samples of the Upper Jurassic Series in the Mohe Basin, Mohe, and Kaikukang formations are studied in detail in terms of petrography, geochronology, and geochemistry. All samples have low compositional and textural maturity, which are located in the areas of dissected arc and basement uplift in Dickinson's discrimination diagrams. LA‐ICP‐MS U–Pb zircon dating yields the youngest concordant ages of 173 ± 4 Ma and 157 ± 3 Ma for the Mohe and Kaikukang formations, respectively, which constrain the maximum sedimentary periods of them. The peak ages of all concordant ages correspond identically to the regional magmatic activities on both the Siberian Craton and Erguna Block. All samples demonstrate geochemical characteristics not so different from the upper continental crust, whose provenance is felsic in lithology and is situated in active continental margins. Thus, a Mohe foreland basin and its binary provenance are strongly suggested, with the Erguna Block – a southern source and the Siberian Craton – a northern one. Based on all the evidence above, a simple tectonic model of the evolution of the Mongol–Okhotsk Ocean is raised, that is, from the Triassic to the Middle Jurassic; the Mongol–Okhotsk oceanic plate continued to subduct under the Siberian Craton and the Erguna Block, triggering intense magmatism in these areas. In the Late Jurassic, the rapid closure of the Mongol–Okhotsk Ocean caused the basement uplift and intense denudation which provided abundant sources of dissected arc and basement materials for the Mohe Basin. [ABSTRACT FROM AUTHOR]

The NE–SW striking Derbugan Fault has been comprehensively accepted as a Mesozoic strike‐slip fault in Erguna Massif rather than a suture belt of Erguna and Xing'an massifs. The rocks exposed within the fault belt, which consist of Jiageda Formation and intrusions which have been multiply deformed and metamorphosed. These deformed rocks provide an ideal opportunity to understand the geodynamics of the uplift history and tectonic evolution of Derbugan Fault in Mongol‐Okhotsk regime and influence of the circum‐Pacific tectonic regime, particularly during the later stages of the Mongol‐Okhotsk Ocean collision. In this study, we report kinematics, meso‐microstructures, quartz EBSD analysis and geochronology data of the Jiageda Formation exposed within the Derbugan Fault belt in Cuogang area, Erguna Massif. The Jiageda Formation and granitic rocks have experienced regional metamorphism and deformation, and is mainly characterised by simple‐shear dominated general shearing with LS tectonites. Our new zircon U‐Pb data of mylonitic rocks from Cuogang area yielded ages between 381 to 401 Ma which was produced as a result of the subduction of the Paleo‐Asian Ocean. Deformed granitic intrusive formed in the Early Triassic (244.8 ± 5.6 Ma) was related to the southward subduction of the Mongol‐Okhotsk oceanic plate beneath the Erguna Massif. The Derbugan Fault represents a ductile to brittle deformation at decreasing crustal level due to the dominant oblique (subhorizontal) slip. The early sinistral strike‐slip deformation with a medium temperature between 450 and 550°C developed at a deep ductile regime resulted from NW–SE extension. The subsequent deformation was essentially brittle that corresponded to a low‐temperature deformation corresponded to a greenschist metamorphic facies. Crystallographic textures indicate a restricted recrystallisation of quartz mainly via dislocation creep through activation prismatic slip and rhomb slip system, with a later activation of basal slip system. The Early Cretaceous extensional environment may consist with the main medium temperature deformation stage of Derbugan Fault, which was related to either delamination or upwelling of the thickened lithosphere of the Mongol‐Okhotsk tectonic regime, and rollback of the Paleo‐Pacific Plate. [ABSTRACT FROM AUTHOR]

Ultrahigh‐temperature (UHT) mafic granulites in the southern part of the Shiguai area in Daqingshan, China, crop out within the Shanheyuan Gneiss of the Khondalite Belt (KB), a Paleoproterozoic tectonic belt in the Western Block of the North China Craton (NCC). The UHT mafic granulites occur within hypersthene‐bearing dioritic–granitic gneiss as irregular lenses and deformed dike swarms. Four metamorphic generation assemblages (M1–M4) are recognized in the studied samples. M1 is defined by the enclosed orthopyroxene and clinopyroxene within the "red eye" corona of the garnet, representing the prograde metamorphic stage. M2 (UHT granulite‐facies) is marked by the appearance of "red eye" corona of the garnet, with mineral assemblages of grt–cpx–opx–pl–ilm–q. M3 is defined by spinel‐rich symplectites between garnet and orthopyroxene, including grt–opx–pl–spl–mt–ilm. M4 (amphibolite facies) is featured by the development of amphibole. Phase equilibrium modelling and some critical thermobarometers are combined to constrain the P–T evolution of the studied samples. The P–T conditions for the M1–M4 are respectively estimated at ~8 kbar/~771–852°C, ~9.4–10.0 kbar/~930–965°C, ~5.0–5.4 kbar/~865–910°C, ~5.0–5.2 kbar/~675–682°C, which define a clockwise P–T path, involving near‐isothermal decompression following the peak metamorphism. The P–T path indicates that the rocks underwent a sequence of tectonothermal processes that started with crustal thickening (M1–M2), followed by rapid crustal uplift (M3) and cooling (M4). This process is inferred that the metamorphism of the UHT mafic granulites was associated with rapid exhumation and uplift that followed the continent–continent collision and amalgamation of the Yinshan and Ordos blocks. This amalgamation formed the Paleoproterozoic KB in the Western Block of the NCC. [ABSTRACT FROM AUTHOR]

In recent decades, the Yanshanian movement in the Mesozoic has been a hotspot of much geological research, attracting numerous studies focusing on regional tectonics, basin evolution, and associated magmatism and volcanic activities. The Haifanggou Formation, exposed in Xingcheng Basin, which is one of intracontinental basins in western Liaoning Province, North China Craton (NCC), comprises mainly conglomerates dominated with interbedded sandstone. Although palaeontology, stratigraphy and lithofacies have been established, its mineralogical compositions and geochronology, even the provenance and implications for Yanshanian movement are still poorly discussed. Available sandstone samples provided a unique opportunity to study the genesis and further deciphered the tectonic mechanisms. The sandstone types of Haifanggou Formation are dominantly litho‐feldspathic litharenite and litharenite. Modal sandstone analysis shows that the origin and deposition mainly are due to arid to semi‐arid weathering and recycling of older rocks and magmatic arcs, eroded and transported debris from eastern NCC. Our new detrital zircon U–Pb ages exhibit that the maximum depositional ages of the Haifanggou Formation were conservatively estimated as late Middle Jurassic (165.6 ± 3.1 Ma). The detrital zircon U–Pb age spectrum of this formation is dominated by several peaks that indicate a provenance from the surrounding rocks including the basement of NCC. The sedimentation of the Haifanggou Formation is deposited under compressional tectonics as a local response of the Yanshanian movement which was related to the subduction of Palaeo‐Pacific Plate. [ABSTRACT FROM AUTHOR]

The Jiutai area is tectonically situated at the eastern segment of the Central Asian Orogenic Belt (CAOB) and is close to the North China Craton (NCC) to the south, serving as an ideal place to investigations of the closure of the Paleo‐Asian Ocean (PAO). Sandstone samples collected from the Yangjiagou Formation and the Lujiatun Formation in this area have been studied in detail in terms of petrology, geochronology and geochemistry. The maximum depositional time of the Yangjiagou and Lujiatun formations has been constrained to early Middle Triassic (ca. 245 Ma) and middle Late Triassic (ca. 219 Ma), respectively. The Yangjiagou Formation, with a major provenance of dissected island arcs, is dominantly composed of Phanerozoic sediments from Northeastern China (NE China) massifs. The Lujiatun Formation, with major sediments from active continental margins, has a relatively larger proportion of Precambrian sediments, in which the ∼1.85 Ga and ∼2.5 Ga sediments are typical of the crystalline basements of the NCC and NE China massifs, which were uplifted and eroded during the closure of the PAO. Besides, both formations show the enrichment in LREEs and the depletion in HREEs, the common Eu negative anomalies, and trace element contents similar to that of the upper continental crust. Based on the provenance analysis of these two formations, the final closure time of the PAO in this area is constrained as from the early Middle Triassic (ca. 245 Ma) to the middle Late Triassic (ca. 219 Ma). [ABSTRACT FROM AUTHOR]

The calcite mylonites in the Xar Moron‐Changchun shear zone show a significance dextral shearing characteristics. The asymmetric (σ‐structure) calcite/quartz grains or aggregates, asymmetry of calcite c‐axes fabric diagrams and the oblique foliation of recrystallized calcite grains correspond to a top‐to‐E shearing. Mineral deformation behaviors, twin morphology, C‐axis EBSD fabrics, and quartz grain size‐frequency diagrams demonstrate that the ductile shear zone was developed under conditions of greenschist facies, with the range of deformation temperatures from 200 to 300°C. These subgrains of host grains and surrounding recrystallized grains, strong undulose extinction, and slightly curved grain boundaries are probably results of intracrystalline deformation and dynamic recrystallization implying that the deformation took place within the dislocation‐creep regime at shallow crustal levels. The calculated paleo‐strain rates are between 10−7.87 s−1 and 10−11.49 s−1 with differential stresses of 32.63–63.94 MPa lying at the higher bound of typical strain rates in shear zones at crustal levels, and may indicate a relatively rapid deformation. The S‐L‐calcite tectonites have undergone a component of uplift which led to subhorizontal lifting in an already non‐coaxial compressional deformation regime with a bulk pure shear‐dominated general shear. This E‐W large‐scale dextral strike‐slip movement is a consequence of the eastward extrusion of the Xing'an‐Mongolian Orogenic Belt, and results from far‐field forces associated with Late Triassic convergence domains after the final closure of the Paleo‐Asian Ocean. [ABSTRACT FROM AUTHOR]

The Mohe Basin, to the south of the eastern Mongol–Okhotsk suture belt, contains important stratigraphic records and thrust‐nappe structures for understanding the closure of the eastern Mongol–Okhotsk Ocean. Meso‐micro structures in the Mohe Formation indicate a low‐temperature deformation/metamorphism (ca. 400°C) under an N‐S compression related to the southward thrusting faulting. The S‐L‐tectonites record strain similar or close to flattening/compressional strain and denote sinistral shearing in analogously N‐S‐trending thrusting. Our new detrital zircon U–Pb ages exhibit that maximum depositional ages of the Mohe Formation were conservatively estimated as latest Middle Jurassic (ca. 165 Ma). The Northeast China and Erguna Block to the south of the Mohe Basin, and Siberian Block to the north were the sources for the Mohe foreland basin's sediments throughout the deposition of the Mohe Formation, which derived from the basement uplift where erosion cuts deep into the dissected arcs. In the latest Jurassic to earliest Cretaceous, the southward collision and indentation of the Siberian Block (final closure of Mongol–Okhotsk Ocean) led to intense thrust nappe structures, syn‐collisional folds, and low‐temperature metamorphism occurred along the northwestern margin of Mohe Basin. [ABSTRACT FROM AUTHOR]

This paper reports U–Pb ages of detrital zircons from a series of clastic and pyroclastic rocks from the Murui Formation in the southern Great Xing'an Range (GXR), NE China, with the aim of constraining the depositional age of this poorly dated unit. These data, combined with the petrographic and sedimentology characteristics of the rocks, are used to constrain the sediment sources and tectonic setting of the provenance and provide wider insight into the tectonic evolution of the southern GXR during the Late Mesozoic. Two lithic arkose samples have dominant age groups at 249–250, 159–160, 136–147, and 394–415 Ma, and 301–323, 278–288, 209–237, and 142–163 Ma, respectively. The U–Pb zircon data constrain the maximum depositional age of the Murui Formation to 136 ± 1 Ma, that is, the Early Cretaceous. A lithic–crystal tuff from the upper Murui Formation yielded zircons with a weighted mean U–Pb age of 136 ± 1 Ma (n = 47, mean square weighted deviation (MSWD) = 2.2), indicating that volcanic activity was contemporaneous with sedimentation of the Murui Formation. U–Pb dating of zircons from a pyromeride in the Baiyingaolao Formation that was erupted unconformably onto the Murui Formation yielded a peak age of ~120 Ma, which constrains the depositional age of the Murui Formation to 120–136 Ma. Further dating of detrital zircons shows a range of ages, indicating the various of sediment origins. The Late Jurassic to Early Cretaceous volcanic rocks in the GXR served as the principal detrital sources for the Murui Formation in the southern GXR. Grain size and modal analysis of the sediments shows that the depositional environment was a stable intracontinental fluvial setting, and the provenance of the detritus was most likely a magmatic arc. According to stratigraphic contact relations, the Baiyingaolao Formation is supposed to have obvious intervals with lower volcanic strata, which combined with disparities between the southern and northern GXR in terms of the duration of volcanism, magmatic events, and the depositional age of the Murui Formation. We can conclude that the restricted occurrence of the Early Cretaceous detritus between the earlier and later phases of volcanism suggests progressive exhumation of the southern GXR in the Early Cretaceous. These may relate to post‐orogenic extension related to oceanic subduction. The southern GXR remained a site of active sedimentation during the continental extension period across the whole of NE China in the Late Jurassic to Early Cretaceous. [ABSTRACT FROM AUTHOR]

Adakite‐like volcanic rocks in the Moguqi area of the central Great Xing'an Range of NE China consist of trachyandesites and trachydacites. These rocks yield LA–ICP–MS U–Pb zircon ages of 229.5–232.6 Ma. These adakite‐like rocks are high in Sr (459–1960 ppm) and MgO (1.2–4.3%), low in Y (11.4–23.70 ppm) and Yb (0.88–2.07 ppm), and have high Sr/Y ratios (37.17–146.31) and high Mg# values (0.43–0.58). These characteristics are similar to those of rocks derived from slab melting. However, the existence of Early Triassic stable continental sedimentary rocks of the Laolongtou Formation does not favour this mode of formation. The zircon εHf(t) values of the samples range from +8.09 to +13.29, indicating the primary magmas were generated by partial melting of juvenile crust. Analysis of geophysical data, combined with the previously published history of the Hegenshan–Heihe Suture in this region and the southward subduction of Mongol–Okhotsk oceanic plate, suggests that the Late Triassic adakite‐like volcanic rocks in the Xing'an Massif formed from the partial melting of delaminated thickened crust in an extensional setting. This occurred after orogenesis involving the Xing'an Massif and the Songnen Massif and was influenced by southward subduction of the Mongol–Okhotsk oceanic plate. [ABSTRACT FROM AUTHOR]

Background and Aims: This study aimed to evaluate the antifibrotic effects of NF-E2-Related Factor 2 (Nrf2) on intestinal fibrosis. Intestinal fibrosis is a common complication of Crohn's disease; however, its mechanism of intestinal fibrosis is largely unclear.Methods: BALB/c mice received 2,4,6-trinitrobenzene sulfonic acid weekly via intrarectal injections to induce chronic fibrotic colitis. They also diet containing received 1% (w/w) tert-butylhydroquinone (tBHQ), which is an agonist of Nrf2. Human intestinal fibroblasts (CCD-18Co cells) were pretreated with tBHQ or si-Nrf2 followed by stimulation with transforming growth factor-β1 (TGF-β1), which transformed the cells into myofibroblasts. The main fibrosis markers such as α-smooth muscle actin, collagen I, tissue inhibitor of metalloproteinase-1, and TGF-β1/SMADs signaling pathway were detected by quantitative real-time RT-PCR, immunohistochemical analysis, and Western blot analysis. Levels of cellular reactive oxygen species (ROS) were detected by dichlorodihydrofluorescein diacetate.Results: tBHQ suppressed the intestinal fibrosis through the TGF-β1/SMADs signaling pathway in TNBS-induced colitis and CCD-18Co cells. Moreover, Nrf2 knockdown enhanced the TGF-β1-induced differentiation of CCD-18Co cells. ROS significantly increased in TGF-β1-stimulated CCD-18Co cells. Pretreatment with H2O2, the primary component of ROS, was demonstrated to block the effect of tBHQ on reducing the expression of TGF-β1. Moreover, scavenging ROS by N-acetyl cysteine could inhibit the increasing expression of TGF-β1 promoted by Nrf2 knockdown.Conclusions: The results suggested that Nrf2 suppressed intestinal fibrosis by inhibiting ROS/TGF-β1/SMADs pathway in vivo and in vitro. [ABSTRACT FROM AUTHOR]