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Subduction leads to voluminous arc magmatism at active continental margins; however, the potential far‐field geodynamic connections with coeval magmatism along opposing passive margins, are rarely investigated. Here we report large‐scale and parallel mafic dike swarms on the South Qinling passive margin, whose geochemical features record the thick and cold subcontinental lithospheric mantle beneath passive margin was gradually replaced by thin and hot one during the early Paleozoic. The subduction of the Proto‐Tethys oceanic lithosphere led to arc magmatism along the active margin, shortly after the rift‐related mafic dike swarms occurred along the passive margin. Subsequent to the continuous oceanic subduction including the ridge‐margin collision, mantle upwelling and slab rollback eventually triggered large‐scale rift‐related magmatism and the opening of new ocean basin at passive margin, and also back‐arc magmatism on the active margin. We highlight slab subduction and pull link the geodynamic processes at active and passive continental margins, which improves our understanding of plate tectonics. Plain Language Summary Large‐scale alkali mafic dike swarms on the South Qinling passive continental margin are associated with a series of parallel faults. Based on the estimated pressures and temperatures of the mantle sources of these dike swarms, we found that the thick and cold subcontinental lithospheric mantle beneath the passive continental margin was gradually replaced by thin and hot one during the early Paleozoic. In addition, arc magmatism on the active margin would slightly precede the dike swarms in passive continental margin. We suggest that the subduction of the Proto‐Tethys oceanic lithosphere led to arc magmatism along the active margin, while rift‐related magmatism occurred along the passive margin of South Qinling. Subsequent to the continuous oceanic subduction including the ridge‐margin collision, mantle upwelling and slab rollback increased the tensional forces on the passive margin, eventually triggering large‐scale rift‐related magmatism and the opening of the ocean. Thus, we suggest the slab pull associated with subduction, and mantle upwelling geodynamicaly link the active and passive continental margin magmatism and leading to the opening of new ocean basins at passive margin. Key Points Large‐scale parallel mafic dike swarms on South Qinling passive continental margin record thinning of the SCLM during Paleozoic Arc magmatism on the active margin of North Qinling and Erlangping Arc slightly precede the dike swarms in South Qinling Slab subduction, pull and mantle upwelling geodynamicaly link the active and passive continental margins

Supercritical fluids are ideal media for mass transfer from the subducting slab into the mantle wedge. However, little is known about the Mg‐Fe isotope compositions of supercritical fluids in subduction zones. Here, we present the Mg‐Fe isotope data for a coesite‐bearing eclogite‐vein system, which is closely associated with supercritical fluids, from the Dabie Orogen in China. The results reveal the geochemical effects of supercritical fluids under subarc conditions. The eclogites close to the eclogitic vein formed by supercritical fluids have not only lighter Mg isotope compositions for whole‐rock but also higher δ26Mg and δ56Fe values in separate minerals than those distant from the vein. The ultrahigh‐pressure eclogitic vein has δ26Mg values of +0.17 to +0.23‰ and δ56Fe values of +0.26 to +0.35‰. These observations indicate that vein‐forming supercritical fluids have heavy Mg‐Fe isotope compositions and are produced by the contributions of omphacite from eclogite during the dissolution‐precipitation process. The supercritical fluids released from eclogite at subarc depths are recovered to have high δ26Mg values of +0.30 to +0.37‰ and δ56Fe values of +0.34 to +0.49‰ and thus can contribute to arc lavas with heavy Mg‐Fe isotopic compositions. On the basis of the mixing modeling between subduction zone fluids and mantle wedge peridotites, we propose that the supercritical fluids have an effect on the mantle wedge to drive it to incorporate slightly heavier Fe isotopes.

The Cenozoic Himalayan leucogranites are generally regarded as the representative S-type granites, derived from partial melting of (meta-)sedimentary rocks in the Higher Himalayan Sequences. This interpretation is challenged by the increasing finding of abundant relict zircons with Cambrian–Ordovician ages in the granites. These ages are lacking in the assumed (meta-)sedimentary sources but are close to the formation timing of early Paleozoic granites (presently as orthogneisses) in the Himalaya. Therefore, it is unclear how the early Paleozoic relict zircons were incorporated into the granites and what the real sources of the Cenozoic Himalayan leucogranites are. This study presents U–Pb ages, trace-element, and Lu–Hf isotope compositions of zircon from both the Cenozoic granites and their country rocks (Paleozoic orthogneisses) from Kuday in the Sakya dome, central Himalaya. Our results indicate that the autocryst zircons from the gneiss samples formed at 494–499 Ma and display obvious negative correlations in the Hf–Ti, Hf–Th/U, and Hf–Eu/Eu* binary plots. Their εHf(420 Ma) values have relatively restricted variations of −7.2 to −0.5. In contrast, the early Paleozoic relict zircons from granites form scattered and contrasting fields in these binary plots with largely varied U–Pb ages (ca. 410–520 Ma) and εHf(420 Ma) values of −35.4 to + 6.7. These observations suggest that the autocryst zircons from gneisses are a cogenetic population and their compositional variations are controlled by crystallization differentiation, whereas the relict zircons from granites were probably originated from sedimentary rocks in which detrital grains were weathered from a variety of protoliths. We argue that the early Paleozoic relict zircon population was not incorporated into the Cenozoic granites by assimilation of the orthogneissic country rocks. This is supported by whole-rock Nd–Hf isotope analyses, which yield εNd(t) and εHf(t) values of −12.6 ~ −12.5 and of −10.4, respectively, for granites and of −8.8 ~ −8.1 and of −5.9, respectively, for orthogneisses (all calculated at 20 Ma). Furthermore, our compiled whole-rock Sr–Nd isotope data indicate that the Cenozoic Himalayan granites differ from the Paleozoic orthogneisses but overlap with the Himalayan (meta-)sedimentary rocks. Phase equilibrium modeling demonstrates that the Paleozoic orthogneisses are relatively infertile due to their low fractions of hydrous minerals and thus low bulk water contents as compared with the metapelites assuming no free fluid is present. Therefore, although the contribution of the Paleozoic orthogneisses cannot be totally precluded, the observed evidence suggests that they are not the main source components of the Cenozoic Himalayan granites. It is speculated that Ordovician and later sediments which can receive the weathered clasts of the early Paleozoic granites can act as the unrecognized sources of the Cenozoic granites. However, more work is required to characterize these sediments before drawing firm conclusions on the sources of these granites.

Okra （Abelmoschus esculentus L. ） is a novel heahhcare vegetable that has been developed rapidly in recent years in China. It contains abundant bioactive substances with significant heahbeare functions. So far, many domestic research institutions have carried out researches about the extraction technology of bioactive substances and their heahhcare functions. At present, tender pods and other organs of A. esculentus are mainly used freshly and directly, but rare products have been processed and developed. In this paper, the research progress of bioactive substances and processing ofA. esculentus was summarized, aiming at providing reference for the deep processing and comprehensive utilization of A. escu/entus in the future in China.

The effect of sodium sulfate on direct reduction of beach titanomagnetite,followed by magnetic separation,to separate iron and titanium was investigated. Direct reduced iron（ DRI） with a high Fe content,low TiO_2 content and low iron recovery was obtained after adding sodium sulfate. When the sodium sulfate dosage was increased from 0 to 10 mass%,the Fe content of the DRI increased from 90. 00 mass% to 93. 55 mass% and the TiO_2 content decreased from 1. 27 mass% to 0. 70 mass%. The reduction mechanism of sodium sulfate was investigated by X-ray diffraction（ XRD） and scanning electron microscopy（ SEM） with energy dispersive spectrometer（ EDS）. Results revealed that the metallic iron grains in the reduced ore with sodium sulfate were larger than those in the ore without sodium sulfate. Sodium sulfate promoted the migration of iron as well as the accumulation and growth of metallic iron grains by low-melting-point carnegieite and troilite formed in the redox system. Low-melting-point carnegieite decreased the melting point of the system and then promoted liquefaction. Troilite could decrease the surface tension and melting point of metallic iron grains.

Relaxin/insulin-like family peptide receptor 2 （RXFP2） is a robust candidate gene related to horn types in sheep. A series of independent genome-wide association studies have reported that RXFP2 underlies the existence and lack of horns. In this study, High-Resolution Melting （HRM） analysis and DNA sequencing were employed to detect the polymorphism of RXFP2 gene in three sheep breeds from Qinghai-Tibet Plateau of China （ Tibetan sheep, Qinghai fine wool sheep and Alpine Merino sheep） and to determine the impacts of genotypes of RXFP2 on expression of horn phenotypes. The results showed that one single nucleotide pol- ymorphism （SNP） was identified as RXFP 2SNP c. 29389966 A 〉 G. The frequency of genotype AA in Alpine Merino ram （polled） was significantly higher than that in Tibetan ram （horned） and Qinghai fine wool ram （horned） Ix2（1, N= 421） = 72.25, P〈 0.001; xZ（1, N= 402） = 4.28, P〈 0.005）]; the fre- quency of genotype AA in Qinghai fine wool ewe （polled） was also much higher than that in Qinghai fine wool ewe （horned） and Tibetan ewe （horned） [x2（1, N = 196） = 42.04, P 〈 0. 001 ; x2 （ 1, N = 192） = 24. 69, P 〈 0. 005 ） ]. This mutation could potentially be exploited in marker-assisted selection （MAS） pro- grams within sheep industry to breed horned or polled animals.

In this paper, the nucleophilic substitution reactions of various N- and P-containing nucleophiles to MBH carbonates of isatins were investigated. Diverse functionalized 3-substituted oxindole derivatives were successfully prepared in satisfactory yields and with high diastereoselectivity. In addition, the base-promoted dimerization of MBH carbonates of isatin afforded the ethylene-bridged bis(3-methylene)oxindole derivatives with nearly 4:1 diastereomeric ratios. The relative configurations of the various polycyclic compounds were clearly elucidated by determination of several single crystal structures.

Adhesion G-protein-coupled receptors (aGPCRs) are important for organogenesis, neurodevelopment, reproduction and other processes 1 – 6 . Many aGPCRs are activated by a conserved internal (tethered) agonist sequence known as the Stachel sequence 7 – 12 . Here, we report the cryogenic electron microscopy (cryo-EM) structures of two aGPCRs in complex with G s : GPR133 and GPR114. The structures indicate that the Stachel sequences of both receptors assume an α-helical–bulge–β-sheet structure and insert into a binding site formed by the transmembrane domain (TMD). A hydrophobic interaction motif (HIM) within the Stachel sequence mediates most of the intramolecular interactions with the TMD. Combined with the cryo-EM structures, biochemical characterization of the HIM motif provides insight into the cross-reactivity and selectivity of the Stachel sequences. Two interconnected mechanisms, the sensing of Stachel sequences by the conserved ‘toggle switch’ W 6.53 and the constitution of a hydrogen-bond network formed by Q 7.49 /Y 7.49 and the P 6.47 /V 6.47 φφG 6.50 motif (φ indicates a hydrophobic residue), are important in Stachel sequence-mediated receptor activation and G s coupling. Notably, this network stabilizes kink formation in TM helices 6 and 7 (TM6 and TM7, respectively). A common G s -binding interface is observed between the two aGPCRs, and GPR114 has an extended TM7 that forms unique interactions with G s . Our structures reveal the detailed mechanisms of aGPCR activation by Stachel sequences and their G s coupling. Adhesion GPCRs involved in cell and matrix interactions signal through a distinct self-cleavage, self-activation mechanism.

A straightforward synthetic protocol for the efficient construction of diazepine-containing spiroindolines has been developed and proceeds through a by base-promoted annulation reaction of α-halogenated N -acylhydrazones and isatin-derived MBH carbonates. The reaction mechanism of this formal [4 + 3] annulation includes the in situ generated allylic ylide, nucleophilic substitution, Michael additon, and elimination processes. Additionally, the similar reaction with α-halogenated N -tosylhydrazones also afforded N -tosyl-substituted spiro[indoline-3,5'-[1,2]diazepine] in satisfactory yields. This protocol provides a convenient approach for the assembly of diverse highly functionalized spiro[indoline-3,5'-[1,2]diazepines] and also features a broad substrate scope, simple reaction conditions, and high molecular convergence.

A convenient synthetic procedure for the construction of novel dispirooxindole motifs was successfully developed by base-promoted three-component reaction of ammonium acetate, isatins and in situ-generated 3-isatyl-1,4-dicarbonyl compounds. The piperidine-promoted three-component reaction of ammonium acetate, isatins and the in situ-generated dimedone adducts of 3-ethoxycarbonylmethyleneoxindoles afforded mutlifunctionalized dispiro[indoline-3,2'-quinoline-3',3''-indoline] derivatives in good yields and with high diastereoselectivity. On the other hand, a similar reaction of the dimedone adducts of 3-phenacylideneoxindoles afforded unique dispiro[indoline-3,2'-pyrrole-3',3''-indoline] derivatives with a cyclohexanedione substituent. A plausible reaction mechanism is proposed to explain the formation of the different spirooxindoles.