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The evolution of unified East Asian continental margin was accompanied by large-scale magmatic and tectonic events. Here we investigate the tectonic evolution history of the ocean-continent connection zone in the eastern South China Block (SCB) during the Mesozoic-Cenozoic subduction of the (Paleo-) Pacific plates based on gravity and magnetic methods that provide a window to the deep crustal structure. The decomposed multi-scale gravity wavelets reveal subduction-related intra-crustal structures and the deep structure of the Mesozoic Greater South China Block (GSCB). The depth of Moho discontinuity was inverted by gravity data, constrained by the latest global crustal model of CRUST 1.0, and the inverted depth is closely consistent with and slightly larger than the depth on seismic profiles. The undulation of the Moho discontinuity beneath the South China Block and the deep supra-crustal faults along the continental margin are considered to be associated with the subduction of the (Paleo-) Pacific plates. In general, the Moho depth in the eastern SCB gets shallower from west to east. The oblique subduction-related strike-slip faults can be traced on the 7.4 km-upward continued field of the magnetic anomaly. The geologically-indistinct Jurassic magmatic arc along the SCB continental margin is verified by residual crustal field of the Bouguer gravity anomaly. The southern Ryukyu-Taroko line is speculated as the inland segment of the Early Jurassic paleo-subduction zone, and represents the southeastern paleo-plate boundary of the GSCB in the Jurassic. As the backarc-arc-forearc paleo-system migrated eastwards since the Early Cretaceous, the subduction zone retreated to the current Taiwan-Okinawa Trough, and the Jurassic magmatic arc-forearc was transformed to a backarc, indicating an eastward migration or jumping of the Yanshanian subduction along the continental margin of the SCB. The tectonic boundary of the Mesozoic GSCB was also identified through the magnetic anomaly field and the high-order gravity field.

The NE China region involves a complex accretionary belt formed by multiple stages of assembly of micro-blocks from the Paleozoic to Mesozoic, the tectonics of which provides important clues on the evolution of the East Asian continental margin. With a view to evaluating the micro-block evolution in NE China, we used gravity and magnetic methods to analyze the geophysical characteristics of the micro-blocks and their boundaries. Combining with regional geology, paleomagnetism and paleontology, we reconstructed the micro-block assembly history in the eastern Central Asian Orogenic Belt. Five Paleozoic to Mesozoic micro-blocks are recognized in NE China: the Erguna, Xing'an, Songnen, Jiamusi and Nadanhada, and their boundaries show significant differences in gravity and magnetic fields. The boundary between the Erguna Block (EB) and the Xing'an Block (XB) shows as a continuous tectonic line in the gravity field, whereas the one between the XB and the Songnen Block (SB) exhibits a rather discrete but strong magnetic anomaly belt. The boundary between the SB and the Jiamusi Block (JB) is characterized by both distinct gravity and magnetic anomalies. The Nadanhada Micro-block (NMB) appears as an independent micro-block in the fourth-order detail field of the Bouguer gravity anomaly, where it shows as a short axis or circinate structure in this anomaly field. The Paleozoic to Mesozoic tectonic evolution of these micro-blocks in NE China is closely related to five sutures in the eastern Central Asian Orogenic Belt. The Xinlin-Xiguitu Suture was first formed at ~500 Ma, leading to the assembly of the EB and the XB, the Heihe-Hegenshan Suture was formed at 320–290 Ma, marking the amalgamation of the XB and the SB, the Mudanjiang-Yilan Suture was formed at ~200 Ma, marking the collision of the JB and the SB. The Paleo-Asian Ocean closed during 250–230 Ma in a scissor style. The subduction of the Paleo-Pacific Ocean was initiated at ~200 Ma. Based on the deep structural architecture imaged from gravity and magnetic anomalies, we propose an evolutionary model of the micro-blocks in the NE China, which provides important insights into the tectonic evolution of the NE China region during the Paleozoic to Mesozoic.

Inorganic cesium lead halide perovskites offer a pathway towards thermally stable photovoltaics. However, moisture-induced phase degradation restricts the application of hole transport layers (HTLs) with hygroscopic dopants. Dopant-free HTLs fail to realize efficient photovoltaics due to severe electrical loss. Herein, we developed an electrical loss management strategy by manipulating poly(3-hexylthiophene) with a small molecule, i.e., SMe-TATPyr. The developed P3HT/SMe-TATPyr HTL shows a three-time increase of carrier mobility owing to breaking the long-range ordering of "edge-on" P3HT and inducing the formation of "face-on" clusters, over 50 % decrease of the perovskite surface defect density, and a reduced voltage loss at the perovskite/HTL interface because of favorable energy level alignment. The CsPbI2 Br perovskite solar cell demonstrates a record-high efficiency of 16.93 % for dopant-free HTL, and superior moisture and thermal stability by maintaining 96 % efficiency at low-humidity condition (10-25 % R. H.) for 1500 hours and over 95 % efficiency after annealing at 85 °C for 1000 hours.

In this paper, a class of high order numerical schemes is proposed to solve the nonlinear parabolic equations with variable coefficients. This method is based on our previous work [10] for convection-diffusion equations, which relies on a special kernel-based formulation of the solutions and successive convolution. However, disadvantages appear when we extend the previous method to our equations, such as inefficient choice of parameters and unprovable stability for high-dimensional problems. To overcome these difficulties, a new kernel-based formulation is designed to approach the spatial derivatives. It maintains the good properties of the original one, including the high order accuracy and unconditionally stable for one-dimensional problems, hence allowing much larger time step evolution compared with other explicit schemes. In additional, without extra computational cost, the proposed scheme can enlarge the available interval of the special parameter in the formulation, leading to less errors and higher efficiency. Moreover, theoretical investigations indicate that it is unconditionally stable for multi-dimensional problems as well. We present numerical tests for one- and two-dimensional scalar and system, demonstrating the designed high order accuracy and unconditionally stable property of the scheme.

Because of the coupling between nanoshell and core, the geometrical parameters of nanoshell have significant influence on the localized electric field factor (LEF) and sensitivity. In this paper, the effects of the inner core radius and the thickness of outer shell on LEF of gold-dielectric-silver (GDS) nanoshell and silver-dielectric-gold (SDG) nanoshell are investigated using quasi-static approximation. The result shows that the longer wavelength has a red-shift, while the shorter wavelength has a blue-shift as the inner core radius increases. The longer wavelength and the shorter wavelength mix together for LEF of GDS nanoshell with increasing the middle dielectric radius, while split for SDG nanoshell. Thus, the effects of geometric parameters on LEF of GDS nanoshell are different from that of SDG nanoshell. In addition, the effects of geometrical parameters on the sensitivity of GDS nanoshell and SDG nanoshell are also studied, a higher sensitivity of nanoshell can be obtained by varying the geometrical parameters. Our study provides a approach to study optical properties of GDS and SDG nanoshell and also broaden their applications in sensor.

Developing efficient metal-organic framework (MOF)-based electrocatalysts with improvable activity and persistence toward the methanol oxidation reaction (MOR) is attracting great research attention but still remains an enormous challenge. Herein, a facile strategy, hydrangea-shaped nickel hydroxide template-directed synthesis of the hierarchically structured Ni-MOF on the Ni(OH)2 heterocomposite (denoted as Ni-Ni) for efficient MOR, is developed. The unique hierarchical structure and synergistic effect of the heterocomposite afford more exposed active sites, a facile ion diffusion path, and improved conductivity, favorable for improving MOR catalytic performance. Remarkably, the optimized Ni-Ni-2 material delivers an excellent activity with a high peak current density (24.6 mA cm-2). Furthermore, to prove the universality of this strategy, NixCu1-x(OH)2 isometallic hydroxide was used as the precursor, and a series of MOF-74/CuxNi1-x(OH)2 (denoted as Ni-NiCu) heterogeneous materials have been prepared and could be used as an effective electrocatalyst to catalyze MOR. The results indicate that this strategy can be used in the synthesis of other new composite materials with specific hierarchical structures for a more efficient electrocatalytic system.

In the paper, we study a high order numerical boundary scheme for solving the complex moving boundary problem on a fixed Cartesian mesh, and numerically investigate the moving rigid body with the complex boundary under the impingement of an inviscid shock wave. Based on the high order inverse Lax-Wendroff (ILW) procedure developed in the previous work (TAN, S. and SHU, C. W. A high order moving boundary treatment for compressible inviscid flows. Journal of Computational Physics, 230(15), 6023–6036 (2011)), in which the authors only considered the translation of the rigid body, we consider both translation and rotation of the body in this paper. In particular, we reformulate the material derivative on the moving boundary with no-penetration condition, and the newly obtained formula plays a key role in the proposed algorithm. Several numerical examples, including cylinder, elliptic cylinder, and NACA0012 airfoil, are given to indicate the effectiveness and robustness of the present method.

We report here a concise, collective, and asymmetric total synthesis of sarpagine alkaloids and biogenetically related koumine alkaloids, which structurally feature a rigid cage scaffold, with L-tryptophan as the starting material. Two key bridged skeleton-forming reactions, namely tandem sequential oxidative cyclopropanol ring-opening cyclization and ketone α-allenylation, ensure concurrent assembly of the caged sarpagine scaffold and installation of requisite derivative handles. With a common caged intermediate as the branch point, by taking advantage of ketone and allene groups therein, total synthesis of five sarpagine alkaloids (affinisine, normacusine B, trinervine, Na -methyl-16-epipericyclivine, and vellosimine) with various substituents and three koumine alkaloids (koumine, koumimine, and N-demethylkoumine) with more complex cage scaffolds has been accomplished.

A composite chiral interface (BSA-MB-MWCNTs) was prepared from bovine serum albumin (BSA), methylene blue (MB), and multi-walled carbon nanotubes (MWCNTs) for chiral recognition of amine enantiomers (1S, 2S)-N,N'-dimethyl-1,2-cyclohexanediamine and (1R, 2R)-N,N'-dimethyl-1,2-cyclohexanediamine. The BSA-based composite was characterized by field emission scanning electron microscopy (FESEM) and ultraviolet-visible spectroscopy (UV-Vis). The electrochemical responses towards the two enantiomers were analyzed via cyclic voltammetry (CV), electrochemical AC impedance method (EIS), and differential-pulse voltammetry (DPV). The experimental results showed that the combination of MWCNTs and BSA could effectively improve the overall identification efficiency, and the peak current displayed by the S-enantiomer is larger, indicating that the prepared chiral surface has stronger interaction with the R-enantiomer. Under optimized condition, the current value of the oxidation peak of the chiral modified electrode showed a good linear relationship towards the amine concentration in the range of 5.0 × 10-3 to 5.0 × 10-5 mmol·L-1 . The proposed electrochemical chiral interface is easy to handle and provides a promising electrochemical sensing platform that can be used to identify chiral amine enantiomers.

This study investigated the performance of anaerobic co-digestion (AcoD) of pig manure and food waste on the reduction of antibiotic resistomes under wet and dry AcoD conditions. High-throughput quantitative PCR technology was utilized for a comprehensive assessment of the performances of the two processes. The results show that dry AcoD with a total solids (TS) content of 20% effectively reduced total antibiotic resistance genes (ARGs) by 1.24 log copies/g wet sample, while only 0.54 log copies/g wet sample was reduced in wet AcoD with a TS content of 5%. Dry AcoD was more efficient in reduction of aminoglycosides, multidrug and sulfonamide resistance genes compared with the reduction of other classes of ARGs. Dry AcoD caused a significant reduction of ARGs with resistance mechanisms of efflux pump and antibiotic deactivation. In contrast, there was no obvious difference in reductions of ARGs with different resistance mechanisms in wet AcoD. Network analysis showed that ARGs were significantly correlated with mobile genetic elements (MGEs) (Spearman's r 0.8, P 0.05), as well as microbial communities. Enrichment of ARGs and MGEs was found at the early period of AcoD processes, indicating some ARGs and MGEs increased during the hydrolysis and acidogenesis stages. But after a long retention time, their abundances were effectively reduced by dry AcoD in the subsequent stages.

A kind of polyurethane rubber (PU)/n-octadecane (n-OD)@silicon dioxide (SiO2)-polymethyl acrylate (PHEMA) form-stable phase change material (PCM) was fabricated in this paper. n-OD@SiO2-PHEMA microcapsules were prepared in one-pot, through interfacial hydrolysis polycondensation of alkoxy silanes and radical polymerization of HEMA. Then, n-OD@SiO2-PHEMA microcapsules were added into PU matrix to obtain PU/n-OD@SiO2-PHEMA composites. SiO2-PHEMA hybrid shell not only provides a shelter for core material, but also increases interfacial bonding between microcapsules with PU and effectively improves the mechanical properties of composites. The morphologies, chemical compositions and crystal structures of microcapsules and composites were characterized by SEM, TEM, FT-IR and XRD methods. The thermal and mechanical properties of the microcapsules and composites were characterized by differential scanning calorimetry and mechanical performance tests. The results show that the thermal and mechanical properties of PU/n-OD@SiO2-PHEMA composites were better than those of neat PU. The PU/n-OD@SiO2-PHEMA composites endow the microcapsules with improved thermal reliability and leakage proof property. The composites were found as form-stable PCM with low leakage rate. The phase change latent heat of the PU/n-OD@SiO2-PHEMA composites was up to 85.1 J/g and the composites can be used for thermal energy storage.

The development of an energy-efficient fractionation process as well as the preservation of the fractionated cellulose, hemicellulose sugars, and lignin are the key to the valorization of lignocellulose. This study presents a mild-condition fractionation process based on a recyclable and bifunctional 4-chlorobenzenesulfonic acid (4-Cl-BSA). The aqueous (e.g., 72%) 4-Cl-BSA solution near-completely fractionated unmilled poplar chips at 50–80 °C for 18–180 min and successively preserved the theoretical maximum yields and key structures of the fractionated cellulose, lignin, and hemicellulose sugars. Around 21.3–27.8% lignin was hydrotropically dissolved at a mesoscale level through accumulation by and complexation with 4-Cl-BSA and its aggregates. The solubilized lignin preserved about 24.7–50.7% of the 61% β-O-4 linkages in the native lignin and about 48.3–82% aromatic units uncondensed. About 72.2–78.7% lignin was insolubilized and quickly deposited on the surfaces of cellulose fibers. Remarkably, the deposited lignin preserved about 61.9–81.1% of the β-O-4 linkages in the native lignin and about 78.2–86.2% aromatic units uncondensed. Hemicellulose sugars and cellulose (millimeter-size, CrI: 71–75, DPᵥ: 910–1022) had high purity and high quality. Compared to the other selected aryl sulfonic acids whether they have or do not have substituents (dichloro, bromo, hydroxyl, and methyl) and mineral acids, 4-Cl-BSA performed better in fractionating unmilled poplar chips and preserving the β-O-4 linkages and aromatic units of lignin. The results indicate that both acidity and hydrophobicity of aryl sulfonic acid greatly influence its fractionation and preservation performances.

An experiment was carried out to study the effect of refrigerant mass flow rate, heat flux density, and saturation temperature on boiling heat transfer coefficient and frictional pressure drop in m...

Let G be a graph that admits a perfect matching M. A forcing set S for a perfect matching M is a subset of M such that it is contained in no other perfect matchings of G. The cardinality of a forcing set of M with the smallest size is called the forcing number of M, denoted by f(G, M). The forcing spectrum of G is defined as: Spec(G) = {f(G, M)∣ M is a perfect matching of G}. In this paper, by applying the Z-transformation graph (resonance graph) we show that for any polyomino with perfect matchings and any even polygonal chain, their forcing spectra are integral intervals. Further we obtain some sharp bounds on maximum and minimum forcing numbers of hexagonal chains with given number of kinks. Forcing spectra of two extremal chains are determined.

In this paper, partly esterified β-cyclodextrin derivative had been synthesized by esterification of β-cyclodextrin and maleic anhydride. Then, it is amidated by diethanolamine. β-Cyclodextrin copolymer had been prepared from amidated β-cyclodextrin derivative, cholic acid and epichlorohydrin in sodium hydroxide aqueous solution. β-Cyclodextrin hydrogel had been prepared through radical polymerization of β-cyclodextrin copolymer, N-isopropylacrylamide and acrylic acid. The structures, compositions and morphology of the hydrogel were characterized by infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry and field-emission scanning electron microscope. Its properties were tested and analyzed by ultraviolet spectroscopy, thermogravimetric analysis and swelling experiments. The results show that the β-cyclodextrin hydrogel owns sustained release performance, temperature and pH sensitivities.

A novel multiphase composite coating composed of Hf0.8Ti0·2B2 solid solution, SiC and Si was prepared by a joint procedure of slurry method and silicon reactive infiltration (SRI). The oxidation and ablation experiments were conducted to investigate oxidation and ablation resistance of the Hf0.8Ti0·2B2–SiC–Si coated graphite samples, respectively. The results revealed that the coated sample was oxidized at 1823 K for 108 h with a mass gain of 1.49%, which was ascribed to the high viscosity oxide layer improved by HfSiO4 and TiO2 in conjunction with dense structure of the coating, thereby presenting excellent high temperature stability. Furthermore, after 90 s ablation at 3273 K under a heat flux of 5.62 MW/m2, the composite coating was not peeled off, which had mass ablation rate (MAR) and linear ablation rate (LAR) of 3.1 mg/s and 1.5 μm/s, respectively. The refractory oxide layer comprising oxides of Hf and Ti on the surface acted as an oxygen barrier, which can weaken the mechanical erosion force of oxyacetylene flame, finally protecting the inner coating and graphite matrix from further consumption.

A nanoprobe based on polydopamine-coated gold nanobipyramids surface modified with molecules of a phenylboronic acid-substituted distyryl boron dipyrromethene has been fabricated and characterised using various physical and spectroscopic methods. It serves as an ultrasensitive sensor for sialic acids on the surface of cancer cells based on its dual surface-enhanced Raman scattering and fluorescence response. This biomarker can also trigger the photodynamic activity of these nanobipyramids, effectively eradicating the cancer cells mainly through apoptosis as shown by various bioassays.

Converting sustainable solar energy into hydrogen energy over semiconductor-based photocatalytic materials provides an alternative to fossil fuel consumption. However, efficient photocatalytic splitting of water to realize carbon-free hydrogen production remains a challenge. Heterojunction photocatalysts with well-defined dimensionality and perfectly matched interfaces are promising for achieving highly efficient solar-to-hydrogen conversion. Herein, we report the fabrication of a novel type of protonated graphitic carbon nitride (PCN)/Ti3C2 MXene heterojunctions with strong interfacial interactions. As expected, the two-dimensional (2D) PCN/2D Ti3C2 MXene interface heterojunction achieves a highly improved hydrogen evolution rate (2181 μmol·g−1) in comparison with bulk g-C3N4 (393 μmol·g−1) and protonated g-C3N4 (816 μmol·g−1). The charge-regulated surfaces of PCN and the accelerated charge transport at the face-to-face 2D/2D Schottky heterojunction interface are the major contributors to the excellent hydrogen evolution performance of the composite photocatalyst.

To shield TiAl alloy from hot corrosion attack, a compact protective coating was fabricated by the combination of aluminizing, anodization and pre-oxidation. The hot corrosion behavior of the coated-TiAl specimen was investigated in the mixture salt consisting of 75 wt.% Na2SO4 and 25 wt.% NaCl at 700 °C. Results indicated that the anodization and pre-oxidation were beneficial to the generation of Al2O3 layer, which could act as a diffusion barrier to prevent the molten salts and oxygen from diffusing into the alloy during exposure to a hot corrosion environment while the aluminizing coating could provide sufficient aluminum source to support the continuous formation of Al2O3 layer. Moreover, the internal stress of the coating was reduced due to the formation of a gradient coating consisting of TiAl3 and TiAl2.

Post-translational modification of proteins plays an important regulatory role in the process of cell life, enabling proteins to have biological activities and perform corresponding functions. The content of post-translational modification proteins in the organism is very low, which makes it commit to a mighty challenge to accurately identify the post-translational modification proteins. The molecular imprinted cavity, which perfectly matches the size, shape, and functional groups of the target molecules, has shown great potential in the separation field. In this paper, the types and characteristics of post-translational modified proteins and molecular imprinting methods were summarized. On this basis, the application of molecular imprinted polymers to the enrichment of post-translational modified proteins was reviewed, and the prospect of its development was prospected.

A vital issue for the fixation and conversion of CO2 into useful chemical products is to find effective catalysts. In this work, in order to develop more effective and diverse catalysts, we implemented the first computational screening study (at M06-2X//B3LYP level) on the cycloaddition of CO2 with aziridines under eighteen metal-substituted HKUST-1 MOFs and tetrabutylammonium bromide (TBAB) as a co-catalyst. For all considered catalytic systems, the ring-opening of aziridine is calculated to be the rate-determining step. Up to 11 M-HKUST-1 systems, i.e., Rh (31.87 kcal mol−1), Y (31.02), Sc (30.50), V (30.02), Tc (29.90), Cd (29.80), Ti (29.32), Mn (29.05), Zn (28.29), Fe (27.85) and Zr (25.09), possess lower ring-opening barrier heights than the original Cu-HKUST-1 (32.90), indicative of their superior catalytic ability to the original Cu-HKUST-1 in theory. With the lowest ring-opening barrier, Zr-HKUST-1 is strongly advocated for future synthetic and catalytic studies.

The ideal magnetohydrodynamics equations are challenging because one needs to maintain the divergence-free condition, $\nabla \cdot { B} = 0$. Many numerical methods have been developed to enforce ...

A facile method for kinetic resolution of [2.2]paracyclophane-derived cyclic N-sulfonylimines based on palladium-catalyzed addition of arylboronic acids was developed, giving two kinds of planar chiral [2.2]paracyclophane derivatives in excellent diastereoselectivities and up to 99% of enantioselectivities with high selectivity factors (s up to 128).

M-ZnFe2O4 (M = Al, Zn, Cu, Mn) nanoparticles, which are potential photocatalysts, were prepared from Fe-bearing solid waste, namely Waelz slag. The valuable elements, namely Fe, Al, Zn, Cu, and Mn, were extracted from the slag simultaneously through sulfuric acid leaching. The extracted elements were converted into sediments in a controlled fashion by manipulating the pH of the lixivium and subsequently transformed into metal-doped ZnFe2O4 nanoparticles using the sol-gel method. The as-synthesised products were characterised using X-ray diffraction, Brunauer-Emmett-Teller analysis, field emission scanning electron microscopy, energy dispersive spectroscopy, UV–vis spectroscopy, and photoluminescence spectroscopy. The photocatalytic performances of the slag-derived M-ZnFe2O4 nanoparticles in photocatalytic methyl orange degradation under visible light were compared with that of undoped ZnFe2O4 nanoparticles. The results indicated that the slag-derived nanoparticles gave better photocatalytic performances than did the undoped sample, with the M-ZnFe2O4 (M = Al, Zn, Cu) sample, which was prepared with precipitates obtained at pH 7, exhibiting the best photocatalytic activity. The enhancement can be attributed to grain refinement and doping.

As one of the most important methods for machining process with high accuracy, ultra-precision grinding is widely used in fields such as aerospace, automotive and mold, etc. Simultaneously, it is common that wheel and spindle axis do not coincide with each other due to wheel settings, machining errors and so on. This could result in the generation of wheel runout, which may reduce the machining surface’s quality. In this paper, combining this phenomenon, an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope theory. After that, the accuracy of this method is verified. Two experiments are carried out on a 5-axis machining center. The artificial runout is set up and calculated utilizing the least square method. Finally, using the presented method, two examples with and without runout are introduced to illustrate the validation of the proposed model. The error due to the runout effect is also analyzed.

The deformation of soft clays under cyclic loading is controlled by microfabric changes. Cyclic triaxial tests, scanning electron microscopy (SEM), and mercury intrusion porosimetry (MIP) were conducted to investigate the deformation and the corresponding micromechanism under cyclic loading. The correlations between the microparameters and deformation of Tianjin soft clay are discussed. The deformation increases linearly in the initial compression stage (number of cycles, N < 500), at a decreasing rate in the later shearing stage (N < 5000), and eventually stabilizes when the cyclic stress ratio (CSR) is 0.30. The probability entropy of both the soil particles and pores have a weak correlation with the deformation on the whole, reflecting a fluctuation within a small range in the initial compression stage. The correlations between the median pore diameter, median particle diameter, and specific surface area and the deformation are validated by using the gray correlation method. More specifically, the specific surface area and the deformation are highly correlated in the initial compression deformation stage. The median pore diameter and median particle diameter are highly correlated with deformation in the later shearing deformation stage.

Background In clinical, common facial papule dermatosis such as seborrheic keratosis (SK), verruca plana (VP), syringoma and lichen nitidus (LN) is often misdiagnosed. Summarizing in vivo reflectance confocal microscopy (RCM) features of the facial papule dermatosis is helpful in the diagnosis of ambiguous lesions. The purpose of this study was to evaluate the features of SK, VP, syringoma, and LN in RCM. Methods We recruited 144 patients referred for unequivocal facial papule dermatosis including 60 patients with SK, 60 patients with VP, 10 patients with syringoma, and 14 patients with LN. The RCM images were evaluated at the epidermis, the dermoepidermal junction, and the dermis from both papule lesions and normal skin. Results In the epidermis, the cerebriform shape was the main RCM characteristic of SK and the "petal-like" structure was the main RCM characteristic of VP. In the dermoepidermal junction, the RCM features we found were as follows: For SK, the bright dermal papillary rings, the abnormal dermal papilla and the looped vessels were also observed at the abnormal dermal papilla. For VP, the bright dermal papillary rings and the point-like blood vessels were also observed at the round dermal papills. For LN, the round, enlarged, well-circumscribed dermal papillae and the enlarged dermal papillaes were heavily laden with individual highly refractive cells. In the dermis, RCM examination revealed brightly refractile teratogenous sweat tube, designing variably visible bright "moon" structures in all syringoma patients. Conclusion Considering our results, RCM may be useful to non-invasively discriminate SK, VP, syringoma and LN in vivo.

Lignocellulosic-biomass-derived transparent nanopaper is an emerging substrate or functional component for next-generation green optoelectronics. The fabrication of such transparent nanopaper typic...

Two new metal-organic coordination compounds with the chemical formulae of [Zn(Htpt)]n (1) and {[Zn(H2tpt)(H2O)]·1/2SO4·2H2O}n (2) based on a multidentate 4-(2,4,6-tricarboxyphenyl)-2,2′,6,2″-terpyridine ligand (H3tpt) have been prepared by hydrothermal synthesis method and structurally characterized. The treatment activity of the compounds on the peripheral artery disease was further explored in the biological section. Firstly, the real time reverse transcription-polymerase chain reaction (RT-PCR) was performed and the expression levels of the peptidyl arginine deiminase were measured. Then, the enzyme linked immunosorbent assay (ELISA) detection kit was used and the content of the inflammatory cytokines was determined. Two new metal-organic coordination compounds have been prepared by hydrothermal synthesis method. The treatment activity of the compounds on the peripheral artery disease was further explored in the biological section. Firstly, the real time reverse transcription-polymerase chain reaction (RT-PCR) was performed and the expression levels of the peptidyl arginine deiminase were measured. Then, the enzyme linked immunosorbent assay (ELISA) detection kit was used and the content of the inflammatory cytokines was determined.

The Congo Basin situated in equatorial Africa is home to the second largest rainforest on the globe and plays an important role in the Earth’s climate system. For instance, the Congo is one of the most convective regions in the world and enhances the tropical large-scale circulation. Although tropical convection is crucial for rainfall and the sustenance of the rainforest, the most intense thunderstorms do not necessarily produce the largest amounts of rainfall over equatorial Africa. Aiming to better understand the decreasing rainfall trend over the Congo, trends in thunderstorm intensity from 1983 to 2018 are analyzed in this paper using the Galvez-Davison index (GDI), i.e., a thermodynamic index used to measure thunderstorm potential. Consistent with previous studies, thunderstorm activity increased during all seasons over the Congo. The GDI suggests that the increasing trends in thunderstorm activity are attributable to an increase in hydrostatic instability. More specifically, the GDI shows that (1) an increase of cold troughs at 500 hPa, (2) an increase in the temperature gradient between 700 and 950 hPa, and (3) a decrease of the equivalent potential temperature ( $${\theta }_{e}$$ ) gradient with height collectively act to promote taller, more intense thunderstorms. This study concludes by proposing feedback mechanisms explaining the intensification of thunderstorms. The mechanisms highlight the cooling and moistening of the mid-troposphere, drying and warming at the surface and lower troposphere, and a decrease in vertical stability and convective inhibition. These factors may act to re-enforce the drying trend which has stressed the Congo rainforest over the past 40-years.

A facile strategy for hydrophobic films based on oil-infused polystyrene microspheres with the unit of γ-methacryloxypropyltrimethoxysilane is demonstrated. Specifically, the rough polystyrene microspheres with unit of γ-methacryloxypropyltrimethoxysilane are synthesized by suspension polymerization. These hydrophobic films were used, for the first time, as rough substrates for loading low surface tension silicone oils as lubricating liquids for the fabrication of polystyrene films. The properties of the films can be well tuned by adjusting the toluene and γ-methacryloxypropyltrimethoxysilane balance of the polystyrene microspheres and the mass ratio of toluene to γ-methacryloxypropyltrimethoxysilane reached 7 : 1.5 was found to be the most effective. The hydrophobic films could easily repel water and the water contact angle of the film was 150° before infusing oil and reached 139° after infusing oil. The morphology, structure and composition of polystyrene microspheres were characterized by SEM and FTIR. The content of trapped lubricant was quantified by silicone oil decomposition and measured by thermogravimetric analysis. Bacterial attachment tests showed that silicone oil infusion inhibited the attachment and growth of E. coli. The resulting films maintain water repellency and slipperiness after freezing, water flowing, and friction.

Titanium silicalite-1 (TS-1) zeolite was successfully synthesized by hydrothermal method in the presence of the tetrapropylammonium hydroxide (TPAOH) template, and a series of TS-1 supported cadmium with different Cd loading (xCd/TS-1) catalysts were carefully prepared to produce epoxidized soybean oil (ESO) through the acid-free catalytic epoxidation of soybean oil (SO) with H2O2. These catalysts were fully characterized using various modern techniques and further evaluated systematically in this epoxidation reaction to understand the relationship between catalytic activity and structure of active components. The results show that the highly dispersed Cd species are introduced on the TS-1 support without affecting the coordination environment of tetrahedral Ti (framework Ti). Furthermore, the Cd species are coordinated with tetrahedral Ti species via O atom resulting in the weakness of the Ti–O bonds and facile attack of the Ti–O bonds by alcohol and H2O2, which can easily form the five-membered intermediate and promote the SO epoxidation process. Furthermore, the deactivation and regeneration behaviors of 2%Cd/TS-1 catalyst in SO epoxidation were also investigated, which reveal that the catalyst deactivation of coke deposition is due to the strong adsorption of the catalysts and SO molecules. But the spent 2%Cd/TS-1 can be completely regenerated by calcination method.

Monolayer (ML) molybdenum disulfide (MoS2) is a novel 2-dimensional (2D) semiconductor whose properties have many applications in devices. Despite its potential, ML MoS2 is limited in its use due to its degradation under exposure to ambient air. Therefore, studies of possible degradation prevention methods are important. It is well established that air humidity plays a major role in the degradation. In this paper, we investigate the effects of substrate hydrophobicity on the degradation of chemical vapor deposition (CVD) grown ML MoS2. We use optical microscopy, atomic force microscopy (AFM), and Raman mapping to investigate the degradation of ML MoS2 grown on SiO2 and Si3N4 that are hydrophilic and hydrophobic substrates, respectively. Our results show that the degradation of ML MoS2 on Si3N4 is significantly less than the degradation on SiO2. These results show that using hydrophobic substrates to grow 2D transition metal dichalcogenide ML materials may diminish ambient degradation and enable improved protocols for device manufacturing.

We have developed a hybrid model that integrates chaos theory and an extreme learning machine with optimal parameters selected using an improved particle swarm optimization (ELM-IPSO) for monthly runoff analysis and prediction. Monthly streamflow data covering a period of 55 years from Daiying hydrological station in the Chaohe River basin in northern China were used for the study. The Lyapunov exponent, the correlation dimension method, and the nonlinear prediction method were used to characterize the streamflow data. With the time series of the reconstructed phase space matrix as input variables, an improved particle swarm optimization was used to improve the performance of the extreme learning machine. Finally, the optimal chaotic ensemble learning model for monthly streamflow prediction was obtained. The accuracy of the predictions of the streamflow series (linear correlation coefficient of about 0.89 and efficiency coefficient of about 0.78) indicate the validity of our approach for predicting streamflow dynamics. The developed method had a higher prediction accuracy compared with an auto-regression method, an artificial neural network, an extreme learning machine with genetic algorithm and with PSO algorithm, suggesting that ELM-IPSO is an efficient method for monthly streamflow prediction.

The upscaling of perovskite solar cells to module scale and long-term stability have been recognized as the most important challenges for the commercialization of this emerging photovoltaic technology. In a perovskite solar module, each interface within the device contributes to the efficiency and stability of the module. Here, we employed a holistic interface stabilization strategy by modifying all the relevant layers and interfaces, namely the perovskite layer, charge transporting layers and device encapsulation, to improve the efficiency and stability of perovskite solar modules. The treatments were selected for their compatibility with low-temperature scalable processing and the module scribing steps. Our unencapsulated perovskite solar modules achieved a reverse-scan efficiency of 16.6% for a designated area of 22.4 cm2. The encapsulated perovskite solar modules, which show efficiencies similar to the unencapsulated one, retained approximately 86% of the initial performance after continuous operation for 2,000 h under AM1.5G light illumination, which translates into a T90 lifetime (the time over which the device efficiency reduces to 90% of its initial value) of 1,570 h and an estimated T80 lifetime (the time over which the device efficiency reduces to 80% of its initial value) of 2,680 h. The upscaling of layer treatments and processing that afford high efficiency and stability in small-area perovskite solar cells remains challenging. Liu et al. show how the efficiency and stability of perovskite modules can be improved using an integrated approach to interface and layer engineering.

Fritillariae Bulbus are the most commonly used antitussive and edible herbs in China. Based on UPLC-QTOF-MS and UPLC-QQQ-MS, the validated MRM-based non-targeted quantitative method was applied to determinate the contents of 48 Fritillaria alkaloids (FAs) in three Fritillaria species (F. thunbergii Miq., F. unibracteata and F. ussuriensis). The RNA-Seq results showed that gene transcript levels have different expression patterns in three Fritillaria species. Based on transcriptome data, the full-length cDNA sequences of squalene epoxidase gene were cloned and characterized. Natural evolution of squalene epoxidase genes resulted in four mutations (C236R, M489L, G510A and K517R) in three Fritillaria species. Molecular docking analysis showed that the 236 residue is located inside the pocket and the binding center while other three residues are located on the surface of the protein. Functional verification indicated the mutations of SQE (C236R) could effectively increase the activity of SQE and obtain higher yield of 2,3-oxidosqualene in recombinant yeast. And the mutations of SQE (M489L and G510A), which increased the hydrophobicity of the protein surface, could also enhance the activity of SQE. This study provides major insights into the metabolites differentiation of FAs biosynthesis, and a firm foundation for the quality control and metabolic engineering of Fritillariae bulbus. Deeper insights into the differentiation of metabolomics and transcriptomics and natural mutations of squalene epoxidase genes in three Fritillaria Bulbus.

Ferulate-5-hydroxylase (F5H) is a key rate-limiting enzyme for the conversion of guaiacyl monolignol (G-monolignol) to syringyl monolignol (S-monolignol) in the specific synthetic lignin pathway, through the catalysis of the 5-hydroxylation of S-monolignol precursors ferulic acid, conifer aldehyde, and coniferyl alcohol. In this study, we cloned the F5H gene of Populus tomenta (PtoF5H), whose product has a highly conserved domain of P450-dependent monooxygenase family. Subcellular localization result demonstrated that PtoF5H protein is an endoplasmic reticulum (ER) resident protein. Furthermore, the PtoF5H was transformed into tobacco in the form of sense- and antisense-, showed that the proportion of S-monolignol increased when PtoF5H gene was overexpressed, suggesting PtoF5H could be used as a target gene for modifying lignin composition. These findings provide further insight into the function of PtoF5H.

In this study, a macroinitiator of β-CD-ONa was prepared by a substitution reaction of β-cyclodextrin (β-CD) with sodium (Na). The macroinitiator was then used in the ring-opening polymerization of octamethylcyclotetrasiloxane (D4) to obtain a star polymer, in which β-CD is the core and polysiloxane is the arm. FTIR, NMR, TGA, CA, etc., were used to characterize the structure and properties of star polymers. The results indicated that there were four polysiloxane arms attached to each β-CD core, and the star polymer had good thermal stability. With the increase in D4 monomer dosage, the hydrophobicity of the star polymer slightly improved, but the reaction time had no significant effect on hydrophobicity. When the star polymer was coated onto polyethylene terephthalate membrane, the transmittance increased from 87.6% to 92.8%, and the haze did not change significantly. Furthermore, the surface of star polymer porous membranes was prepared by the static breath-figure method using n-hexane as solvent at 30 °C. The results showed uniform pore distribution and increased hydrophobicity.

Traditional statistical pattern identification methods, such as artificial neural network and support vector machine, have limited ability to identify minor damage of bridges. Deep learning can mine the inherent law and representation level of sample data. As a typical algorithm of deep learning, convolutional neural network is a feedforward neural network with deep structure and convolution calculation, and its ability of image identification is very outstanding. The recurrence graph of structural response can reveal the internal structure, similarity, and damage information. The original structure response signal involves the coupling vibration of vehicle and bridge is filtered and reconstructed by wavelet packet, and then the recurrence graph of different damage cases is obtained, which is used as the input image of convolutional neural network as a new type of damage feature; thus, a damage identification method based on convolutional neural network and recurrence graph is established. The results of numerical simulation and model experiment show that the recurrence graph contains more damage information; compared with the traditional statistical pattern identification methods, convolutional neural network can achieve more accurate feature extraction and identification through intelligent learning layer by layer, so as to realize more accurate identification of damage location and damage degree.

Recently, heteroatom-doped carbon has been widely used in various fields because of their inexpensive and abundant resources, especially in oxygen reduction reaction. Here, the 1-butyl-3-methlyimidazolium hexafluorophosphate (BmimPF6) is explored as the precursor to offer phosphorus and fluorine, and melamine as a supporter to provide nitrogen. The N, P, F-tridoped mesoporous carbons are obtained by pyrolyzing the homogeneous mixture of melamine and BmimPF6, without any post-processing. This composition of the carbon can be used as a potential metal-free electrocatalyst for oxygen reduction reaction (ORR). Notably, the optimized N, P, and F tri-doped mesoporous carbon obtained at 900 °C, exhibits good electrocatalytic performance for ORR, with high electron-transfer number, great methanol crossover tolerance, and outstanding durability. This work may provide a new case to synthesis heteroatom-tridoped carbon for energy conversion and storage.

Paper cultural relics are prone to embrittlement, yellowing, powdering, mildew and damage due to the brittleness of materials, natural deterioration, microbial corrosion, and man-made destruction. To prolong the expected life of paper cultural relics, a series of novel microcrystalline cellulose/TiO2/fluorine/styrene-acrylate coatings were prepared with modified microcrystalline cellulose, modified nano-TiO2, dodecafluoroheptyl methacrylate, and several acrylate monomers. The prepared coatings were analyzed by infrared spectroscopy, transmission electron microscopy, UV–Vis spectroscopy, and performance-testing devices. In addition, the optimized protective coatings were coated on the simulated paper cultural relic surface, and its protective effects were evaluated by tensile strength retention rate and weight loss rate. When the content of modified nano-TiO2 was 1.0 wt%, the protective coatings exhibited good hydrophobicity, oil repellency, mechanical strength, anti-aging, and reversibility.

y High specific power, high stowed packing efficiency, low processing cost, and high tolerance against environmental threats (high energy and charged particle radiation) make perovskite solar cell (PSC) a promising candidate for power generation in space. However, vacuum, as encountered in space, causes perovskite outgassing, raising concern for its long-term stability. In this work, we find that PSCs (ITO/SnO2/perovskite/Spiro-MeOTAD/Au) degrade ten times faster upon reducing the pressure from 9 x 10(4) to 5 x 10(3) Pa during operation, due to acceleration of the perovskite transformation and ion migration. Gas permeability of the layers atop perovskite and mobile ion-induced chemical reactions at charge transporting layers and related interfaces are two critical factors. We develop a PSC structure (ITO/PTAA/perovskite/PCBM/ZnO/AZO/[Ni/Al grid]) that effectively mitigates vacuum and illumination-induced degradation pathways, enabling PSCs to realize a low PCE loss rate of 0.007%/h over 1,037 h at the maximum power point under 100 mW cm(-2) illumination at 5 x 10(3) Pa.

A ZrB2–SiC–TaSi2–Si coating on siliconized graphite substrate was prepared by a combination process of slurry brushing and vapor silicon infiltration. The high-temperature oxidation behavior and cracking/spallation resistance of the as-prepared coating were investigated in detail. It was revealed that the oxidation kinetics at 1500 °C in static air followed a parabolic law with a relatively low oxidation rate constant down to 0.27 mg/(cm2·h0.5). The crack area ratio of the as-prepared coating was determined as 3.8 × 10−3 after severe thermal cycling from 1500 °C to room temperature for 20 times. Apart from the formation of ZrO2 as skeleton phase with SiO2 as infilling species, the good oxidation and cracking/spallation resistance of the coating also could be attributed to its unique duplex-layered structure, i.e., a dense ZrB2–SiC–TaSi2 major layer filled with Si and an outermost Si cladding top layer. Meanwhile, the strong adhesion strength of the SiC transition layer with the graphite substrate and the outer ZrB2–SiC–TaSi2–Si layer was a vital factor as well.

Na3V2(PO4)2F3 attracts lots of attention due to its high plateau, three-dimensional ion diffusion channel and small volume deformation. However, it suffers from low intrinsic electrical conductivity. To improve the electrochemical performances, carbon incorporation is a common way. Interestingly, an unknown plateau at 3.4 V vs. Na/Na+ usually appears in the charge and discharge profile of Na3V2(PO4)2F3/C using carbon thermal reduction method. To understand this phenomenon, a mechanism involving fluorine loss and structure transformation during heat treatment of Na3V2(PO4)2F3/C is proposed. In the existence of carbon, fluorine in Na3V2(PO4)2F3 is not stable and Na3V2(PO4)2F3 would transform to Na3V2(PO4)3, V2O3 and Na3VF6. Based on this phenomenon, we fabricated a high performance cathode material based on Na3V2(PO4)2F3 and Na3V2(PO4)3 for sodium-ion batteries. High energy, high rate and long cycle are achieved by integration of high energy Na3V2(PO4)2F3, stable Na3V2(PO4)3, highly conductive V2O3, and sodium ion active Na3VF6. These findings can enrich the understanding of vanadium-based polyanion cathode materials for energy storage and may arouse interest in studies of hybrid cathode materials for batteries.

Menthae Haplocalycis Herba has been utilized for food and medicinal purposes in China for thousands of years. It has various efficacies, including dispelling wind and heat and relieving sore throat. M. Haplocalycis Herba has been also widely used in food, cosmetics, spices, and other fields. Exploring the constituents and detecting the metabolites of M. Haplocalycis are of great significance to clarify the effective substances. However, the in vivo metabolites of M. Haplocalycis Herba water extract are still unclear. Herein, a sensitive and specific method, ultra-high performance liquid chromatography with linear ion trap-Orbitrap mass spectrometry, established in this assay was used to study the metabolism of M. Haplocalycis Herba water extract in rat plasma, urine, and feces. We characterized and identified 9, 50, and 34 metabolites in plasma, urine, and feces, respectively. Seven metabolic pathways, including phase Ⅰ (isomerization, demethylation, hydroxylation, and dehydration) and phase Ⅱ (sulfation and glucuronidation) were mainly involved in the metabolism. It is the first systematic study on the metabolism of M. Haplocalycis Herba water extract in vivo, which enrich current understanding of the metabolic behavior of M. Haplocalycis Herba water extract and provide a metabolic rationale for further in-depth in vivo biotransformation and pharmacokinetic analysis.

Yellowtail kingfish, Seriola lalandi, is a globally distributing pelagic marine fish species. In recent years, the wild population has suffered drastic decline due to overfishing and environmental deterioration. Thus, the sustainable utilization and conservation management for this species should be implemented urgently. In the present study, we developed SNP markers using 2b-RAD sequencing method from 33 individuals of yellowtail kingfish. Wherein, 100 high-quality SNP markers were obtained based on high throughput sequencing and stringent SNP filter process. The minor allele frequency of these SNPs ranged from 0.0126 to 0.4957. The observed heterozygosity and expected heterozygosity ranged from 0 to 0.9914 and 0.0249 to 0.5000, respectively. The inbreeding coefficient varied from − 0.9828 to 0.7882. Among these SNPs, 10 loci deviated significantly from Hardy–Weinberg equilibrium after Bonferroni correction. These novel SNP markers will serve as valuable tools for population genetics evaluation and natural resources conservation of yellowtail kingfish.

Considering the low conversion and long reaction time in scaling up reaction in batch reactor, the organocatalyzed epoxidation reaction of styrene was intensified under continuous flow conditions using a commercial fluidic reactor (Corning Advanced Flow G1 Reactor). After investigating the effect of reaction temperature, catalyst amount, MeCN/t-BuOH ratio, FO/FAB (buffer solution amount), total feed flow rate and operating mode on the epoxidation reaction, the optimal reaction conditions were identified under continuous flow conditions. Upon optimization, high conversion and excellent selectivity with short reaction time (3.17 min) can be obtained. We successfully developed a process for the rapid and continuous epoxidation of styrene using an organocatalyst with hydrogen peroxide as the oxidant. Compared with the batch conditions, the continuous flow reactor can exhibit unique advantages including high-speed, safety, continuousness and absence of amplifying effect, which will be significant for the industrial production of epoxides.

The (6E,7E)-N1,N4-bis((pyridin-2-yl)methylene)benzene-1,4-diamine ligand L-0 was prepared in order to synthesize the corresponding pyridine imine metal (iron, cobalt and nickel) complexes Fe-1, Co-2 and Ni-3. The structures of the ligand and its corresponding metal complexes were characterized by element analysis, NMR, IR, UV–Vis and ESI–MS. Upon activation with cocatalyst, the metal complexes Fe-1, Co-2 and Ni-3 exhibited moderate catalytic activity, and the oligomer products were mainly 1-butene. The influence of reaction parameters, such as solvent type, Al/M (M = Fe, Co, Ni) molar ratio, reaction temperature, reaction pressure and cocatalyst type, on catalytic properties was investigated in detail. Ethylene oligomerization data suggested that metal center had an important impact on catalytic performance. In most cases, attributed to electron effects, Fe-1 had better catalytic activity than Co-2 and Ni-3 at the same reaction conditions, and Ni-3 had better catalytic selectivity toward high-carbon olefins (≥ 1-decene). The density functional theory calculations were utilized to optimize the geometry structure for exploring the relationship between structure and catalytic properties, which provides a possibility of predicting the catalytic selectivity in ethylene oligomerization. Moreover, the catalytic mechanism was further studied for better understanding of ethylene oligomerization process catalyzed by Fe-1, Co-2 and Ni-3. The para-phenylene-linked pyridine imine metal (iron, cobalt and nickel) complexes have the ability of catalyzing ethylene oligomerization. Attributed to electron effects, their catalytic properties including activity and selectivity are different.

A finite difference method was employed to evaluate the effect of secondary reinforcement on the performance of Geosynthetic-Reinforced Retaining (GRR) walls. The two-dimensional numerical models used a Cap-Yield soil constitutive model to represent the behavior of backfill. The numerical model was first calibrated and verified by the measured results from a full-scale field test. A parametric study was then performed to investigate the effects of secondary reinforcement length, secondary reinforcement stiffness, secondary reinforcement connection, and secondary reinforcement layout. The numerical results show that an increase in secondary reinforcement length and stiffness can reduce the deflection of the GRR wall and the maximum tensile stress of primary reinforcement. The mechanical connection of secondary reinforcement can also reduce the wall facing deflection and result in relatively small maximum tensile stress and connection stress in the primary reinforcement as compared with no connection to the secondary reinforcement. In addition, a wall with fewer but longer secondary reinforcement layers at certain elevations had relatively smaller wall facing deflections than the baseline case. This comparison demonstrates that more optimal layout of secondary reinforcement exists that could further reduce the maximum wall facing deflections and create a better performing wall while the same or less amount of geosynthetic reinforcement material is used.

A significant declining trend in rainfall over the Congo basin has been observed over the past three decades. Since the Madden–Julian oscillation (MJO) is a major forcing mechanism for tropical convection and rainfall, the interannual variability and trend in rainfall over the Congo may be partly attributable to variability or changes in the MJO. This study explores the long-term (1979–2018) relationship between the active MJO diagnosed by the real-time multivariate (RMM) MJO phase index data and observed rainfall and cloud data over the Congo during October–March. Since the MJO may significantly enhance rainfall during the wet phases or suppress rainfall during the dry phases, the crux of this paper includes how trends in MJO activity may impact the overall observed precipitation trend over the Congo. The relationship between MJO activity and rainfall over the Congo was documented using statistical techniques and composite analysis. A new, yet simple approach was developed to partition seasonal rainfall depending on the MJO phase (i.e., wet, dry, inactive, and other). Results show a significant correlation between the number of wet and dry MJO days, and rainfall enhancement and suppression over the Congo. While there exists considerable interannual variability in MJO activity and rainfall over the Congo, there is a significant increase in the number of dry MJO days (3.47 days decade−1) which tends to intensify the large-scale drying trend over the Congo during October–March. The increasing trend in the number of dry MJO days is likely enhancing the net drying trend by 13.6% over the Congo.