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Plate subduction links the Earth’s surface and interior and may change the redox state of the Earth’s mantle. Mantle wedges above subduction zones have high oxygen fugacity compared with other mantle reservoirs, but the cause is debated. Here we analyze high-pressure metamorphic rocks derived from ferromanganese pelagic sediments in the Qilian subduction complex, northwest (NW) China. We show that progressive metamorphism is a process of reducing reactions, in which Mn4+ is reduced to Mn2+. On the global scale, such reactions would release significant amounts of oxygen (~1.27 × 1012 g year−1), estimated from the global flux of MnO in sediments passing into subduction zones. This budget is sufficient to raise the oxygen fugacity of the mantle wedge, hence arc magmas, to a higher level than other mantle reservoirs. In contrast, ferric iron (Fe3+) enters hematite, aegirine, and garnet, without valence change and plays little role in the oxidation of the mantle wedge. Fe3+ remains stable to depths of >100 km but will transfer to the deeper mantle along with the subducting slab. The manganese reduction process provides a new explanation for high oxygen fugacity in the mantle wedge.

Porphyry Mo deposits are important suppliers of molybdenum for industrial applications, but the origin and source of metals in these deposits remain debated. Here, we present Mo isotope data for Miocene mineralized porphyritic monzogranites (MPMs) and Paleocene barren biotite monzogranites and tuffs (BMTs) from the Bangpu porphyry Mo (Cu) deposit in the Gangdese metallogenic belt. The results show that the MPMs display radiogenic Sr and Pb isotopes and elevated δ98/95Mo (relative to NIST SRM 3134; +0.07‰–1.2‰) and Mo contents, which exceed the range of the depleted mantle. These characteristics cannot be attributed to surface weathering, hydrothermal alteration, magmatic differentiation, or partial melting but rather reflect the incorporation of Mo from black shales into their magma sources, as evidenced by the significant correlations between δ98/95Mo and εNd(t) and aluminum saturation index (ASI) values. In contrast, the BMTs display lower Mo and δ98/95Mo values than the mineralized samples, and their δ98/95Mo values display no correlations with radiogenic isotopes or ASI values. The contrasting characteristics of mineralized and barren samples provide strong evidence that the addition of black shales played an important role in the formation of the Bangpu porphyry Mo deposit. Our study thus establishes a possible link between porphyry Mo deposits and organic-rich sediments and highlights the great potential of Mo isotopes in studying porphyry Mo deposits.

The Chinese Loess Plateau (CLP) is the largest loess deposit on Earth with expansive surface-exposed source rocks of varying origins, ages, and history. Here, we present abundances of elements on representative loess and palaeosol samples from seven classic sections of the CLP. Most elements, including soluble elements (e.g. Rb and Cs), show significant correlations with La or Al2O3. These correlations indicate that these elements are hosted or absorbed in particle minerals during weathering, transport, and deposition (e.g. mica, K-feldspar, and clay minerals). These new observations allow the use of La/X (‘X’ being the element of interest) and the estimated La abundance of 31 ppm in the model upper continental crust (UCC) to estimate the abundances of other elements. The results show higher Cs (Cs = 6.7 ± 1.2 ppm), lower transition metals, Ba, and Ga. Given the high CaO and presence of carbonate in UCC rocks of both vast western China (the primary source for the CLP) and eastern China, we propose that these updates on the element abundances represent a refined model for the carbonate-bearing UCC.

Whether or not oceanic crust basalts are affected by plate subduction is a hot topic of debate. The South China Sea is one of the largest marginal basins in the western Pacific Ocean and has been surrounded by subduction of the Pacific plate and Indian plate, yet, to date, no study has clearly shown evidence of subduction in the geochemistry of volcanism in the basin due to a lack of sampling of igneous crust basalts on the seafloor. The International Ocean Discovery Program Expedition 349 cored seafloor basalts near the fossil spreading ridges of the eastern (Site U1431) and southwestern (Site U1433 and U1434) subbasins in the South China Sea. The recovered basalt samples indicated a pyroxenite-bearing peridotite mantle source. Here, we report Mg isotopic data from 14 of these oceanic crust basalt samples. The δ26Mg values of most basalts from the three drill holes were higher (up to −0.10‰) than that of the average mantle (−0.25‰). The lack of correlations of δ26Mg with geochemical indices of magmatic processes (e.g., MgO, CaO/Al2O3, La/Sm, Nb/Zr) suggests that crystal fractionation and partial melting had insignificant effects on the Mg isotopic compositions of the South China Sea basalts. Thus, the variations in Mg isotopes were inherited from their mantle sources. Considering the highly varied Ce/Pb ratios and elevated 87Sr/86Sr values but mantle-like 143Nd/144Nd values, we propose that the varied δ26Mg values were likely caused by metasomatism of subduction-released fluids. The coupling of Mg and Sr-Fe isotopes provides robust evidence that the high-δ26Mg values of the South China Sea basalts resulted from mixing among pyroxenite-bearing peridotite mantle, the nearby Hainan plume materials, and subducting serpentinite-released fluids. Therefore, these Mg isotopes suggest that the mantle source of the South China Sea basalts was influenced by subducted materials, providing further evidence of the initial expansion, formation, and evolution of the South China Sea during plate subduction.

Objective To investigate the quantitative correlation between the osteotomy end displacement and the occurrence of transfer metatarsalgia in percutaneous minimal invasion surgery of bunion in the forefoot loading pattern.Methods The simulation of the operation of minimally invasive treatment of hallux valgus using the established finite element model with the period of forefoot load mode facilitated the correction of the distal end of the first metatarsal head after osteotomy by steps of 0–6 mm from inside to outside and from top to bottom; each displacement distance was 2 mm. The stress data were collected and analyzed at the osteotomy end and under each metatarsal head in the gait cycle, the quantitative correlation between the vertical and horizontal displacement and between the stress changes under the first and second metatarsal heads was clarified. Then, the correlation between the pressure changes of the first and second metatarsal heads in the gait cycle and the occurrence of postoperative transfer metatarsalgia was analyzed, and accurate quantitative indicators of displacement during the operation were identified.Results The forefoot loading pattern of the gait cycle assessed in the finite element model before and after percutaneous minimal invasion surgery of hallux valgus showed that when the horizontal displacement is 4 mm, the correlation between the pressure x at the distal end of the osteotomy (under the first metatarsal) and the corresponding pressure y under the second metatarsal is negative, the R value is -0.894, and the quantitative correlation is y=-0.6504x + 0.5232 with increasing vertical displacement. When the vertical displacement is 4 mm, the stress under the first metatarsal increases with the increase in horizontal displacement. Conversely, the pressure under the second metatarsal decreases. Both have a high correlation with horizontal displacement, with R values of 0.981 and − 0.890. Also, in this interval, the pressure x at the distal end of the osteotomy (under the first metatarsal) has the highest correlation with the corresponding pressure y under the second metatarsal head, the R value is -0.830, and the quantitative correlation equation is y=-0.4528x + 0.4159.Conclusion When the distal end of the first metatarsal osteotomy is shifted outwards by 4 mm, and the metatarsal side is shifted by 4 mm through bone setting manipulation during operation, percutaneous minimal invasion surgery of hallux valgus can reduce or cure hallux valgus. This might elevate the metatarsal pain during forefoot loading and avoid transfer metatarsalgia after hallux valgus operation.

Background: We aimed to explore catalpol and NF-k. The role of antidepressant and anti-inflammatory effects of b inhibitor in depression induced by chronic unpredictable mild stress (CUMS). Methods: Under the guidance of Qiqihar Medical University, from January 2020 to January 2021, the weight, sucrose consumption and rest time of mice during swimming were monitored, the neurobehavioral changes of rats under CUMS were used to determine the experimental model; ELISA detection of iNOS, ROS, caspase-1, IL-1 β And IL-18 expression level; Western blotting detection of TLR4, MAPK and NF-κB expression level; LPS-induced cell model. INOS, NLRP3, caspase-1, IL-1 in RT-qPCR and ELISA detection models β And IL-18 expression level;the TLR4, MAPK and NF-κB level were detected by Western blotting. Results: CUMS can make rats lose weight, reduce sucrose consumption rate and prolong rest time. Catapol can enhance this effect; In the depression model, ROS, NLRP3, NF-κ B and iNOS were up-regulated Catalpol group MAPK, NF-κ Reduced expression of B and TLR4; ROS, caspase-1, IL-1β, IL-18 and iNOS protein increased. Cell model group TLR4, MAPK and NF-κ. The high protein content of B decreased in catalpol group. Conclusion: Catalpol acts as anti-depressant and anti-inflammatory molecule indepression induced by CUMS. Combination of catalpol with NF-κB inhibitor might play a role in the treatment of depression through regulating the neuroinflammation.

Background Minimally invasive treatment of hallux valgus is one of the better surgical methods,which still has the shortcomings of insufficient correction of deformities and poor correction of hallux rotation. Therefore, we have improved the surgical method to further improve the clinical efficacy. Methods 186 patients(328 feet) who were diagnosed as hallux valgus from January 2019 to January 2020 and underwent DMMO were included in this retrospective study. The preoperative and postoperative hallux valgus angle (HVA), intermetatarsal angle (IMA) and distal articular set angle (DASA) of the patients were collected and compared to evaluate the correction of deformity. To explore the safety and effectiveness of DMMO in improving the function of hallux valgus based on American Orthopaedic Foot & Ankle Society (AOFAS) and visual analogue score (VAS). Results The preoperative HVA, IMA and DASA of the subjects were (33.63°±8.74°,12.95°±2.42°,9.46°±1.88°), postoperative HVA, IMA and DASA were (11.18°±2.04°,7.61°±1.46°,3.25°±1.15°); The preoperative AOFAS and VAS were (49.65 ± 9.32,5.61 ± 2.12), and the postoperative were (90.21 ± 7.65,1.65 ± 0.48).The postoperative(12 months) of HVA, IMA, DASA, AOFAS and VAS were better than those before operation (P Level of Evidence:Level III

To generate a high-spatial-resolution hyperspectral (HHS) image from a high-spatial-resolution multispectral (HMS) image, both spatial information and spectral information should be considered simultaneously if we want to build a more accurate mapping from HMS to HHS. To this end, a spectral and spatial jointed spectral super-resolution method is proposed in this letter using an end-to-end learning strategy for each subspace with the cluster-based multibranch backpropagation neural network (BPNN). More specifically, in addition to the spectra similarity, a modified superpixel segmentation is introduced to jointly take spatial contextual information into account, and a new framework with it is given. Comparisons on the Columbia University Automated Vision Environment (CAVE) data set show that our proposed method outperforms other relative state-of-the-art methods more than 0.3 in the root mean squared error (RMSE) and more than 1.0 in the spectral angle mapper (SAM) index. Especially, an exemplary application is demonstrated using the synchronized observation data collected by the multispectral and hyperspectral sensors mounted on the HJ-1A satellite at the same time.

Anomalies in remote sensing images are generally reflected in two aspects of spatial and spectral ones, as for the anomaly detection of sea surface using multispectral or hyperspectral images, spectral information is more important. To this end, a novel spectral anomaly detection method based on dictionary optimization is proposed in this letter. More specifically, the normal scene is first defined to distinguish the anomaly. Then, without any assumption about the distribution of anomaly, a spectral dictionary is formulated and derived theoretically with optimization to express the normal scenes. Using the sparse and low-rank constraints, the alternating direction method of multiplier (ADMM) is employed to solve the above optimization in the spectral domain. Finally, for a given sea-surface image to be detected, the error matrix that cannot be fully expressed by the optimized spectral dictionary is regarded as anomalies. It shows certain generality for various kinds of spectral anomalies on the sea surface. Taking multispectral images obtained by the HY-1C satellite as an example, comparisons with related state-of-the-art methods demonstrate that our proposed method achieves the best anomaly detection performance not only for oil-spill pollution but also for algae pollution.

Performances of three data processing methods in terms of accuracy and precision for in situ Fe isotope analysis were investigated.

Purpose: To investigate the effect of miR-486 on rats with acute myocardial infarction (AMI), and its mechanism of action.Methods: A rat model of AMI was established. They were randomly divided into 4 groups, namely, sham, model, agomiR-486 and antagomiR-486 groups, respectively. Rats in these different groups were treated with agomiR-21 (5 μL, 40 nmol/mL), antagomiR-21 (5 μL, 40 nmol/mL) or agomiR-NC (5 μL, 40 nmol/mL), respectively. Then, key miRNAs were sorted out using gene-chip assay and verified by quantitative reverse transcription polymerase chain reaction (qRT-PCR) assay. Luciferase reporter gene assay was conducted to determine the interaction between miR-486 and gene of PTEN. After intraperitoneal injection of agomiR-486 and antagomiR-486, hemodynamics was measured to determine the effect of miR-486 on myocardial function of the rats. The effect of miR-486 expression level on the expression of myocardial enzymes in serum, the morphology of myocardial tissues, and the apoptosis of myocardial tissues in rats, were investigated. Additionally, the effect of miR-486 expression level on PTEN/AKT signaling pathway in the rats was determined by Western blotting.Results: The results of gene-chip and qRT-PCR assays revealed that there were 8 differentially expressed genes in rat myocardial tissues in the model group when compared with the sham group. MiR-486 improved the cardiac function of rats and the morphology of myocardial tissues, but reduced AMI-induced apoptosis of myocardial cells and the expression of myocardial enzymes (markers of myocardial injury) in a dose-dependent manner (p < 0.05). The results of luciferase reporter gene assay showed that PTEN was a direct target of miR-486. In rat models of AMI, a raised expression of miR-486 remarkably suppressed the protein expression level of PTEN and up-regulated that of p-AKT/AKT (p < 0.05).Conclusion: MiR-486 protects against AMI in rats probably by targeting PTEN and activating the AKT signaling pathway. The results of the current study may provide new insights for the treatment of AMI.

Ethylene in principle can be obtained via oxidative coupling of methane (OCM), but it is urgently calling for a low-temperature active and selective catalyst. To accomplish this goal, the CexZr1-xO2 solid solutions with varied Ce/Zr molar ratio were modified with Mn2O3-Na2WO4 to fabricate OCM catalysts. The effects of Ce/Zr ratio and Mn2O3-Na2WO4 doping were investigated on the catalyst reactivity for the OCM, showing that the reaction light-off temperature, activity and selectivity are subject to the Ce/Zr molar ratio and Mn2O3-Na2WO4 doping. The promising catalyst with Ce/Zr molar ratio of 0.15/0.85 achieves 25% CH4 conversion with 67% selectivity to C2-C3 at 660 °C and is stable for at least 100 h. The catalysts were systematically studied by CH4-TPSR, O2-TPO/-TPD, CH4-pulse, in-situ FT-IR, EPR and XPS, showing that the Mn2O3-Na2WO4 doped Ce0.15Zr0.85O2 can generate more O2– species thereby leading to a markedly improved activity and selectivity at much lowered reaction temperature.

Canola and wheat are the main oilseed crop and grain crop, respectively, and they often have similar phenological stages. The understanding of the interactions between microwave signals with wheat and canola in different stages is important for their monitoring using synthetic aperture radar (SAR) imagery. This paper investigates the characteristics of canola and wheat through the use of backscattering profiles from multi-year Sentinel-1 images. Large fluctuations are observed for the temporal backscattering profiles of canola and wheat in different growth statuses induced by agrometeorological conditions in different years. The capability and stability of Sentinel-1 for wheat and canola mapping is further investigated using single- and multi-temporal SAR images hosted in Google Earth Engine (GEE) using the random forest classifier. Although different agrometeorological conditions and field managements make the temporal profiles of backscattering variations, the large difference in canopy structure allows SAR images to make the separability of canola and wheat stable on Sentinel-1 images in different phenology stages. The classification accuracies and the feature importance scores from multi-temporal classification in different years show that the backscattering features obtained at flowering to maturity stages make more contributions to the good-quality mapping of canola and wheat than those at other stages. The F1 scores of canola and wheat achieve 0.95 during the canola flowering and podding period, and the minimum F1 scores of 0.85 were also obtained at other stages. These findings show that SAR images have great potential in the good-quality mapping of canola and wheat in a wide phenology window.