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[Display omitted] Researchers are interested in single-atom catalysts with atomically scattered metals relishing the enhanced electrocatalytic activity for nitrogen reduction and 100 % metal atom utilization. In this paper, we investigated 18 transition metals (TM) spanning 3d to 5d series as efficient nitrogen reduction reaction (NRR) catalysts on defective 2D SiP V layered structures through first-principles calculation. A systematic screening identified Mo@SiP V , Nb@SiP V , Ta@SiP V and W@SiP V as superior, demonstrating enhanced ammonia synthesis with significantly lower limiting potentials (−0.25, −0.45, −0.49 and −0.15 V, respectively), compared to the benchmark −0.87 eV for the defective SiP. In addition, the descriptor Δ G *N was introduced to establish the relationship between the different NRR intermediates, and the volcano plot of the limiting potentials were determined for their potential-determining steps (PDS). Remarkably, the limiting voltage of the NRR possesses a good linear relationship with the active center TM atom Ɛ d , which is a reliable descriptor for predicting the limiting voltage. Furthermore, we verified the stability (using Ab Initio Molecular Dynamics − AIMD) and high selectivity (U L (NRR)- U L (HER) > -0.5 V) of these four catalysts in vacuum and solvent environments. This study systematically demonstrates the strong catalytic potential of 2D TM@SiP V (TM = Mo, Nb, Ta, W) single-atom catalysts for nitrogen reduction electrocatalysis. [ABSTRACT FROM AUTHOR]

Purpose: This retrospective study aimed to investigate whether the repair of medial meniscus posterior root tears (MMPRTs) is effective for improving clinical outcomes and return to sports rates in young patients (50 years old or younger) with medial compartment knee osteoarthritis (KOA) and MMPRTs. Methods: Between 2016 and 2019, 153 patients with KOA and MMPRTs who underwent open‐wedge high tibial osteotomy (OWHTO) were retrospectively included. The patients were divided into OWHTO combined with MMPRT repair (n = 73) and isolated OWHTO (n = 80) groups. Lysholm scores, Hospital for Special Surgery (HHS) scores, Tegner scores, flexion contracture, range of knee flexion, return to sports rates and postoperative complications were compared. Radiological outcomes, including hip–knee–ankle angle (HKA), medial proximal tibial angle (MPTA), joint line convergence angle (JLCA) and Kellgren–Lawrence (K‐L) grade, were compared between the two groups. Results: After a mean follow‐up of 30.1 ± 3.0 months, the OWHTO + Repair group observed better clinical outcomes compared with the OWHTO group (Lysholm score: 86.7 ± 7.4 vs. 81.6 ± 6.9, p = 0.023. HHS score: 85.4 ± 8.20 vs. 80.5 ± 7.1, p = 0.039). The OWHTO + Repair group had higher Tegner scores and return to sports rates than the OWHTO group (Tegner score: 6 vs. 5, p = 0.020; return to sports rates: 38% vs. 15%, p = 0.001). No fracture or major complications occurred. Radiological outcomes showed no significant differences between the two groups (HKA: 181.1 ± 2.7 vs. 180.1 ± 1.5 n.s; MPTA: 90.1 ± 1.8 vs. 89.2 ± 1.4, n.s; JLCA:1.9 ± 0.7 vs. 2.1 ± 0.7, n.s). Conclusions: Additional MMPRT repair during OWHTO was associated with better clinical outcomes and higher rates of return to sports in young patients with medial compartment KOA and MMPRTs. Level of Evidence: Level III. [ABSTRACT FROM AUTHOR]

The CO2 electrochemical reduction reaction (CO2RR) is one of the most promising methods to reduce carbon dioxide emissions and store energy. At the same time, the pathways of CO2 reduction reaction are diverse and the products are abundant. Converting carbon dioxide to C2+ products, a critical feedstock, requires a C–C coupling step with the transfer of more than 10 electrons per molecule and, hence, is kinetically sluggish. The production of some key adsorptions is conducive to the formation of C2+ products. In this work, we used in situ techniques to figure out the reason why hexagonal-close-packed (hcp) Co nanosheets (NSs) have high activity in CO2RR to ethanal. According to the in situ Raman spectra, the high local pH environment on the catalyst surface is favorable for CO2RR. The high pH at low potentials not only suppresses the competing hydrogen evolution reaction but also stimulates the production of COCO* intermediate. The isotopic labeling experiment in differential electrochemical mass spectrometry (DEMS) provides a possible sequence of the products. The 13CO is generated when we replace 12CO2 with 13CO2, which identifies the origin of the products. Besides, in situ electrochemical impedance spectroscopy (EIS) shows that the hcp Co at −0.4 V vs. RHE boosts the H2O dissociation and proton transfer, feeding sufficient H* for CO2 to *COOH. In the end, by analyzing the transmission electronic microscopy (TEM), we find that the Co (002) plane may be beneficial to the conversion of CO2 and the adsorption of intermediates. [ABSTRACT FROM AUTHOR]

Background: Arginase-1 (ARG1) promotes collagen synthesis and cell proliferation. ARG1 is highly expressed in various tumour cells. The mechanisms of ARG1 in epithelial-to-mesenchymal transition (EMT)-associated cataracts were studied herein. Methods: C57BL/6 mice, a human lens epithelial cell line (HLEC-SRA01/04), and human lens capsule samples were used in this study. The right lens anterior capsule of the mouse eye was punctured through the central cornea with a 26-gauge hypodermic needle. Human lens epithelial cells (HLECs) were transfected with ARG1-targeted (siARG1) or negative control siRNA (siNC). For gene overexpression, HLECs were transfected with a plasmid bearing the ARG1 coding sequence or an empty vector. Medium containing 0.2% serum with or without transforming growth factor beta-2 (TGF-β2) was added for 6 or 24 h to detect mRNA or protein, respectively. The expression of related genes was measured by quantitative real-time polymerase chain reaction (RT–qPCR), western blotting, and immunohistochemical staining. Transwell assays and wound healing assays were used to determine cell migration. Cell proliferation, superoxide levels, nitric oxide (NO) levels, and arginase activity were estimated using Cell Counting Kit-8 assays, a superoxide assay kit, an NO assay kit, and an arginase activity kit. Results: ARG1, alpha-smooth muscle actin (α-SMA), fibronectin, and Ki67 expression increased after lens capsular injury, while zonula occludens-1 (ZO-1) expression decreased. Fibronectin and collagen type I alpha1 chain (collagen 1A1) expression increased, and cell migration increased significantly in ARG1-overexpressing HLECs compared with those transfected with an empty vector after TGF-β2 treatment. These effects were reversed by ARG1 knockdown. The arginase-related pathway plays an important role in EMT. mRNAs of enzymes of the arginase-related pathway were highly expressed after ARG1 overexpression. ARG1 knockdown suppressed these expression changes. Numidargistat (CB-1158) dihydrochloride (CB-1158), an ARG1 inhibitor, suppressed TGF-β2-induced anterior subcapsular cataract (ASC) by reducing the proliferation of lens epithelial cells (LECs) and decreasing fibronectin, α-SMA, collagen 1A1, and vimentin expression. Compared with that in nonanterior subcapsular cataract (non-ASC) patients, the expression of ARG1, collagen 1A1, vimentin, fibronectin, and Ki67 was markedly increased in ASC patients. Conclusions: ARG1 can regulate EMT in EMT-associated cataracts. Based on the pathogenesis of ASC, these findings are expected to provide new therapeutic strategies for patients. Plain English summary: Fibrotic cataracts can be classified as anterior subcapsular cataract or posterior capsular opacification depending on where fibrosis occurs. The mechanism of fibrotic cataracts is not fully understood. Fibrotic opacities induced by trauma, inflammation, or radiation can accumulate underneath the anterior lens capsule, causing anterior subcapsular cataract. Posterior capsular opacification is one of the most common complications of phacoemulsification with intraocular lens implantation, with a high incidence in young patients. We show for the first time that ARG1 can regulate EMT in fibrotic cataracts. TGF-β2 is the main cause of fibrosis in LECs. The expression of ARG1 and fibronectin in LECs increased after TGF-β2 treatment or mouse lens capsular injury. We investigated the specific molecular mechanisms by which ARG1 regulates EMT in fibrotic cataracts. The mRNA expression of enzymes of the arginase-related pathway was decreased due to knockdown of ARG1 expression in HLECs. These effects were reversed by ARG1 overexpression. Additionally, knockdown of ARG1 decreased collagen 1A1, fibronectin, and vimentin expression; superoxide levels; and cell migration and increased NO levels. These effects were reversed by ARG1 overexpression. Pharmacological blockade of the ARG1 pathway with CB-1158 reduced the proliferation of LECs and decreased fibronectin, α-SMA, collagen 1A1, and vimentin expression in mouse lenses. We believe that ARG1 promotes the production of collagen 1A1 by directly activating the arginase pathway and leads to lens fibrosis by reducing NO production and increasing superoxide levels, providing a new mechanism for the prevention and treatment of fibrotic cataracts. 2rJpd8qCKY4LBSvBN5cEnm Video Abstract [ABSTRACT FROM AUTHOR]

Nanoparticle-based drug delivery systems have become a favourable platform for target specificity in disease treatment, although their side effects and toxicity remain controversial. Plant polysaccharide nanoparticles are safe, natural biomaterials that have become candidate materials for nano-drug delivery systems due to their excellent biodegradability and biocompatibility. In addition to becoming candidate materials, plant polysaccharide nanoparticles show excellent pharmacokinetic and drug delivery characteristics as carrier materials to manipulate small drug molecules at the nanoscale, mainly improving medicine solubility, reducing medicine toxicity and side effects and enhancing biological targeting of medicines. Therefore, the application of plant polysaccharide nanoparticles in the field of drug delivery systems may become the focus of future studies. Here we review the carrier function of plant polysaccharide nanoparticles as a polymeric material in drug delivery. The limitations and challenges of applying plant polysaccharide nanoparticles in drug carrier systems are highlighted with the aim to provide a reference for their precise development. [ABSTRACT FROM AUTHOR]

3D reconstruction of crops is important for researching their biological properties, canopy light distribution and robotic harvesting. However, the complex field environment makes the real-time 3D reconstruction of crops difficult. Due to the low-textured in the field, it is difficult to obtain effective features to construct accurate and real-time 3D maps of the field from existing single-feature SLAM methods. In this paper, we propose a novel RGB-D SLAM based on point-line feature fusion for the real-time field 3D scene reconstruction. By optimizing the point-line features joint poses, we first build a 3D scene map of the field based on the point-line feature structure. Then, a joint point cloud filtering method is designed based on the keyframes optimization of the point-line feature. Finally, we obtain the consistently high-quality dense map in the global respect. The overall performance in terms of pose estimation and reconstruction is evaluated on public benchmarks and shows improved performance compared to state-of-the-art methods. Qualitative experiments on the field scenes show that our method enables real-time 3D reconstruction of crops with high robustness. • A point-line feature fusion optimization method is proposed to improve the accuracy of pose estimation. • A keyframe optimization strategy and a dense map optimization scheme are proposed to achieve a globally consistent dense map. • A real-time RGB-D SLAM method is presented for field 3D scenes reconstruction based on point-line feature fusion. [Display omitted] [ABSTRACT FROM AUTHOR]

Staphylococcal nuclease domain-containing protein 1 (SND1) is an evolutionarily conserved multidomain protein, which has gained attention recently due to its positive regulation in several cancer progression and metastatic spread. However, the specific contribution of SND1 glycosylation in glioma remains uncertain. In the current study, we confirmed that SND1 was highly expressed in human glioma. Using site-directed mutagenesis, we created four predicted N-glycosylation site mutants for SND1 and provided the first evidence that SND1 undergoes N-glycosylation on its Asn50, Asn168, Asn283, and Asn416 residues in human glioma U87 cells. In addition, we found that removing the N-glycans on the Asn50 site destabilized SND1 and led to its endoplasmic reticulum-associated degradation. Furthermore, destabilized SND1 inhibits the glioma cell proliferation and metastasis. Collectively, our results reveal that N-glycosylation at Asn50 is essential for SND1 folding and trafficking, thus essential for the glioma process, providing new insights for SND1 as a potential disease biomarker for glioma. [ABSTRACT FROM AUTHOR]

This paper studies the influence of large-size cave on pressure transient characteristics in fracture-caved carbonate gas reservoirs (FCCGR). With the rapid increase of energy demand, the exploration and development of unconventional oil and gas becomes more and more important. In recent years, many FCCGR have been discovered in western China and contribute significantly to Chinese gas reserves. However, with the presence of large-size cave, FCCGR have complex pore structures and strong heterogeneity. Traditional pressure transient analysis models cannot describe the gas flow accurately. This paper develops a novel pressure transient analysis model for FCCGR by coupling the fluctuating pressure and minor energy loss. Based on the solutions, the typical curves are plotted to analyze the pressure transient characteristics. It is found that the flow process can be subdivided into six stages, including the following: (I) wellbore storage, (II) first transition stage, (III) cave storage, (IV) second transition stage, (V) interporosity flow, and (VI) radial flow. The findings indicate that a concave is added, and the wellbore storage occurs earlier due to the existence of cave. Then, the influences of key parameters are studied. The pressure propagation coefficient and cave volume factor influence the stages I, II, III, and IV. When pressure propagation coefficient increases, the wellbore storage becomes larger and cave storage becomes smaller. The first concave moves to upper right. When cave volume factor increases, the wellbore storage occurs earlier and the curves move left in stage I. Interporosity flow factor and storage ratio influence the location and depth of the second concave. Finally, a field gas well is interpreted by using the proposed model, which verifies the reliability and correctness of the model. The findings of this study can help to better understand the influence of large-size cave on pressure transient characteristics. In addition, it can help engineers invert the cave volume, which is of great significance for the development in FCCGR. [ABSTRACT FROM AUTHOR]

OBJECTIVE An improved QuEChERS method was established and verified for simultaneous determination of isoxaflutole and its metabolites diketonitrile and benzoic acid analogue residues in corn and plants. This method was mainly used to study the digestion rule and final residue level of isoxaflutole and its metabolites in corn and plants. It was hoped that the safe use of isoxaflutole in corn can be achieved eventually. METHOD: The method was completed by means of ultra‐performance liquid chromatography with triple quadrupole mass spectrometry. The extraction of the target substance was through acetonitrile solution containing 1% acetic acid, and the purification was through primary secondary amine, octadecylsilane and graphitized carbon black sorbent. RESULTS: In the method, the quantitative limits and detection limits of the three analytes were 0.005–0.01 and 0.001–0.003 mg kg−1 respectively. The half‐life of isoxaflutole in the plants in Shandong and Anhui was 36.4 and 42.1 days respectively, and the digestion dynamics all conformed to the first‐order kinetics. The final residues of isoxaflutole in green corn and mature corn were less than 0.02 mg kg−1 of the maximum residue limit set by the Codex Alimentarius Commission. CONCLUSIONS: The residual amount of isoxaflutole in corn and plants at harvest time was acceptable when isoxaflutole was applied once at a dose of 121.5 g a.i. ha−1. © 2021 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Background: Apoptosis signal-regulating kinase 1-interacting protein 1 (AIP1) participates in inflammatory neovascularization induction. NADPH oxidase 4 (NOX4) produces reactive oxygen species (ROS), leading to an imbalance in nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) and NLR family pyrin domain containing 6 (NLRP6) expression. The mechanisms of AIP1, NOX4, ROS and inflammasomes in corneal neovascularization were studied herein. Methods: C57BL/6 and AIP1-knockout mice were used in this study. The alkali burn procedure was performed on the right eye. Adenovirus encoding AIP1 plus green fluorescence protein (GFP) (Ad-AIP1-GFP) or GFP alone was injected into the right anterior chamber, GLX351322 was applied as a NOX4 inhibitor, and then corneal neovascularization was scored. The expression of related genes was measured by quantitative real-time polymerase chain reaction, western blotting and immunofluorescence staining. 2′,7′-Dichlorofluorescin diacetate staining was used to determine the ROS levels. Results: The expression of AIP1 was decreased, while that of cleaved interleukin-1β (clv-IL-1β) and vascular endothelial growth factor A (VEGFa) was increased after alkali burn injury. NOX4 expression was increased, the imbalance in NLRP3/NLRP6 was exacerbated, and corneal neovascularization was increased significantly in AIP1-knockout mice compared with those in C57BL/6 mice after alkali burns. These effects were reversed by AIP1 overexpression. NLRP3/NLRP6 expression was imbalanced after alkali burns. GLX351322 reversed the imbalance in NLRP3/NLRP6 by reducing the ROS levels. This treatment also reduced the expression of clv-IL-1β and VEGFa, suppressing neovascularization. Conclusions: AIP1 and NOX4 can regulate corneal inflammation and neovascularization after alkali burn injury. Based on the pathogenesis of corneal neovascularization, these findings are expected to provide new therapeutic strategies for patients. Plain English summary: Corneal alkali burn injury is a common type of ocular injury that is difficult to treat in the clinic. The cornea is a clear and avascular tissue. Corneal neovascularization after alkali burn injury is a serious complication; it not only seriously affects the patient's vision but also is the main reason for failed corneal transplantation. Corneal neovascularization affects approximately 1.4 million patients a year. We show for the first time that AIP1 and NOX4 can regulate corneal inflammation and neovascularization after alkali burns. The expression of AIP1 was decreased, while that of clv-IL-1β and VEGFa was increased after alkali burns. We tried to elucidate the specific molecular mechanisms by which AIP1 regulates corneal neovascularization. NOX4 activation was due to decreased AIP1 expression in murine corneas with alkali burns. NOX4 expression was increased, the imbalance in NLRP3/NLRP6 was exacerbated, and corneal neovascularization was increased significantly in AIP1-knockout mice compared with those in C57BL/6 mice after alkali burns. These effects were reversed by AIP1 overexpression. Additionally, NLRP3/NLRP6 expression was unbalanced, with NLRP3 activation and NLRP6 suppression in the corneal alkali burn murine model. Eye drops containing GLX351322, a NOX4 inhibitor, reversed the imbalance in NLRP3/NLRP6 by reducing ROS expression. This treatment also reduced the expression of clv-IL-1β and VEGFa, reducing neovascularization. Therefore, we provide new gene therapeutic strategies for patients. With the development of neovascularization therapy, we believe that in addition to corneal transplantation, new drug or gene therapies can achieve better results. 4JfT1-9DioSts9dbj1op36 Video Abstract [ABSTRACT FROM AUTHOR]

Accurate and reliable building footprint maps are vital to urban planning and monitoring, and most existing approaches fall back on convolutional neural networks (CNNs) for building footprint generation. However, one limitation of these methods is that they require strong supervisory information from massive annotated samples for network learning. State-of-the-art semi-supervised semantic segmentation networks with consistency training can help deal with this issue by leveraging a large amount of unlabeled data, which encourages the consistency of model output on data perturbation. Considering that rich information is also encoded in feature maps, we propose to integrate the consistency of both features and outputs in the end-to-end network training of unlabeled samples, enabling to impose additional constraints. Prior semi-supervised semantic segmentation networks have established cluster assumption, in which the decision boundary should lie in the vicinity of low sample density. In this work, we observe that for building footprint generation, low-density regions are more apparent at the intermediate feature representations within the encoder than the encoder’s input or output. Therefore, we propose an instruction to assign the perturbation to the intermediate feature representations within the encoder, which considers the spatial resolution of input remote sensing imagery and the mean size of individual buildings in the study area. The proposed method is evaluated on three datasets with different resolutions: Planet dataset (3 m/pixel), Massachusetts dataset (1 m/pixel), and Inria dataset (0.3 m/pixel). Experimental results show that the proposed approach can well extract more complete building structures and alleviate omission errors. [ABSTRACT FROM AUTHOR]

Oxygen blocking the porous transport layer (PTL) increases the mass transport loss, and then limits the high current density condition of proton exchange membrane electrolysis cells (PEMEC). In this paper, a two-dimensional transient mathematical model of anode two-phase flow in PEMEC is established by the fluid volume method (VOF) method. The transport mechanism of oxygen in porous layer is analyzed in details. The effects of liquid water flow velocity, porosity, fiber diameter and contact angle on oxygen pressure and saturation are studied. The results show that the oxygen bubble transport in the porous layer is mainly affected by capillary pressure and follows the transport mechanism of 'pressurization breakthrough depressurization'. The oxygen bubble goes through three stages of growth, migration and separation in the channel, and then be carried out of the electrolysis cell by liquid water. When oxygen breaks through the porous layer and enters the flow channel, there is a phenomenon that the branch flow is merged into the main stream, and the last limiting throat affects the maximum pressure and oxygen saturation during stable condition. In addition, increasing the liquid water velocity is helpful to bubble separation; changing the porosity and fiber diameter directly affects the width of pore throat and the correlative capillary pressure; increasing porosity, reducing fiber diameter and contact angle can promote oxygen breakthrough and reduce the stable saturation of oxygen. • Investigation on water channel flow coupled with oxygen transport in PTL. • Perspective of 'pressurization-breakthrough-depressurization' mechanism. • Precise interface capture of oxygen bubbles by numerical simulation. • Correlation between throat size, merge of oxygen paths, and pressure profile. • A feasible simulation method for investigating the two-phase flow in PEMEC. [ABSTRACT FROM AUTHOR]

Accurate and reliable building footprint maps are of great interest in many applications, e.g., urban monitoring, 3D building modeling, and geographical database updating. When compared to traditional methods, the deep-learning-based semantic segmentation networks have largely boosted the performance of building footprint generation. However, they still are not capable of delineating structured building footprints. Most existing studies dealing with this issue are based on two steps, which regularize building boundaries after the semantic segmentation networks are implemented, making the whole pipeline inefficient. To address this, we propose an end-to-end network for the building footprint generation with boundary regularization, which is termed RegGAN. Our method is based on a generative adversarial network (GAN). Specifically, a multiscale discriminator is proposed to distinguish the input between false and true, and a generator is utilized to learn from the discriminator's response to generate more realistic building footprints. We propose to incorporate regularized loss in the objective function of RegGAN, in order to further enhance sharp building boundaries. The proposed method is evaluated on two datasets with varying spatial resolutions: the INRIA dataset (30 cm/pixel) and the ISPRS dataset (5 cm/pixel). Experimental results show that RegGAN is able to well preserve regular shapes and sharp building boundaries, which outperforms other competitors. [ABSTRACT FROM AUTHOR]

• We propose a novel cascaded framework to reconstruct 3D faces with subtle details. • By detaching details from the texture, we enhance the recovered geometry details. • We design a staged strategy to capture details over multiple scales. Despite tremendous success has been achieved in faithfully reconstructing face shapes from single images, recovering accurate local details still remains challenging. Previous works propose reprojection-based methods to improve the performance of detail recovering – they render a textured 3D shape into an image and make it approximate to the input during iterations. However, details from textures and shapes are mixed in the rendered image when minimizing the re-projection loss, which leads to limitations in detail recovery. To address this issue, we propose a novel 3D face reconstruction framework that 1) uses a coarse-medium-fine strategy to capture details while preserving the global shape, 2) disentangles details from the texture to enhance local accuracy, and 3) applies a phased optimization to recover details over multiple scales. Experiments demonstrate the capability of our framework to reconstruct high-fidelity face shapes with accurate, fine details. [ABSTRACT FROM AUTHOR]

Microbial co-culture has proven to be an effective way to improve the ability of microorganisms to biocontrol. However, the interactive mechanisms of co-cultural microbes, especially between fungi and bacteria, have rarely been studied. By comparative analysis of morphology, transcriptomics and metabolomics, the interactive mechanisms of a sequential co-culture system of Trichoderma asperellum HG1 and Bacillus subtilis Tpb55 was explored in this study. The results revealed that co- culture has no significant effect on the growth and cell morphology of the two strains, but lead to mycelium wrinkling of HG1. RNA-seq analysis showed that co-culture significantly upregulated the HG1 genes concerning amino acid degradation and metabolism, proteolysis, resisting environmental stress, cell homeostasis, glycolysis, the glyoxylate cycle, and the citric acid (TCA) cycle, while Tpb55 genes related to cell homeostasis, spore formation and membrane fluidization were significantly upregulated, but genes associating to TCA, glycolytic cycles and fatty acid β -oxidation were significantly downregulated. Metabolomic results revealed that some amino acids related to energy metabolism were significantly altered in HG1, whereas palmitic acid, which is related to cell membrane functions, was upregulated in Tpb55. These results indicated that HG1 could interfere with carbon metabolism and cell membrane fluidity, but accelerate spore formation of Tpb55. Biophysical assays further convinced that co-culture could decrease ATP content and inhibit ATPase activity in HG1, and could promote spore formation and reduce the cell membrane fluidity of Tpb55. In addition, co-culture also accelerated the production of intracellular anti-oomycete compound octhilinone. The above results indicate that HG1 and Tpb55 are mainly in a competitive relationship in the co culture system. These findings provide new insights for understanding the interaction mechanism between co cultured microbes. [Display omitted] [ABSTRACT FROM AUTHOR]

Transcranial magnetic stimulation (TMS) is a noninvasive technology used to treat certain brain disorders. As an important part of the TMS system, the stimulation coil induces the electric field (EF) in the brain, which can change the excitability of nerve tissue. First, a three-layer multicoil (TLMC) is proposed on the basis of the principle of superposition and cancellation of magnetic field (MF). The simulation results in COMSOL show that this structure can significantly improve focality and stimulation strength, but it reduces the depth of stimulation. Second, a novel improved particle swarm optimizer (PSO) is proposed with three improved strategies. The novel improved PSO has higher convergence accuracy and stability in the test function. Finally, we utilized the novel improved PSO to optimize the current configuration and rotation angle of the TLMC three times. The numerical results show that the TLMC after the second optimization can increase stimulation strength by 19.10% on the basis of satisfying the stimulation depth of 15 mm. Compared with the unoptimized, the optimized TLMC can better balance the focality and stimulation depth. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthetic PIV image is generated based on DNS velocity. • Three methods are compared in the processing of PIV image. • Estimations of epsilons could deviate largely from the DNS results. • Hybrid method performs better in velocity and epsilon quantification. The turbulent energy dissipation rate is an important parameter that determines the transfer rates of mass, heat and momentum in chemical engineering industry. Especially in a multiphase reactor, the local instantaneous turbulent dissipation rate affects the breakage and coalescence of bubbles or droplets. To directly determine the local turbulent dissipation rate, fluctuating velocity gradients have to be measured down to the Kolmogorov length scale. This paper compares the advantages and disadvantages of three different methods, namely, correlation method, optical flow method and hybrid method, in the evaluation of velocity fields, which are subsequently used to calculate the turbulent dissipation rate. An instantaneous flow field of homogeneous isotropic turbulence from DNS results is used as a benchmark. The velocity field and turbulent dissipation rate field obtained by these three methods are compared to the DNS results. It is shown that the hybrid method performs better in both velocity field evaluation and local turbulent dissipation rate estimation compared to the other two methods. This is because the hybrid method combines the advantages of the correlation method in achieving a stable averaged velocity field and the optical flow method in achieving pixel-level resolution measurement of the flow field. [ABSTRACT FROM AUTHOR]

To evaluate the efficacy of microwave ablation (MWA) and MWA plus monochemotherapy in elderly patients with advanced non-small-cell lung cancer (NSCLC). Patients with advanced NSCLC aged ≥70 years were retrospectively enrolled. MWA was performed at the primary tumor site. The end points included progression-free survival (PFS), response to MWA and overall survival (OS). Fifty-four patients were enrolled; of these, 36 received monochemotherapy. Complete ablation was achieved in 42 patients (77.8%). The median PFS and OS were 4.9 months and 21.8 months, respectively. Univariate analyses showed that female patients had superior PFS (31.9 months [95% confidence interval (CI): 0.8–63.0]) vs. 5.0 months in male patients (95% CI: 2.0–8.0), p =.002). Female sex was associated with better OS (not reached vs. 10.8 months, 95% CI: 9.3–12.3, p =.003). Moreover, patients with primary tumor size <3.5 cm had better OS than those with tumor size ≥3.5 cm (not reached vs. 10.9 months, 95% CI: 8.2–13.6, p =.006). Multivariate analyses showed that no characteristics were independent prognostic factors of PFS, but sex and primary tumor size were independent prognostic factors of OS. MWA was effective in the treatment of elderly patients with advanced NSCLC. [ABSTRACT FROM AUTHOR]

In the late stage of underground brine mining in salt lakes, the method of injecting fresh water is often used to extract the salt from the brine storage medium. This method of freshwater displacement breaks the original water–rock equilibrium and changes the evolution process of the original underground brine. To explore the mechanism of salt release in saline water-bearing media under conditions of relatively fresh lake water dissolution, this paper analyzes the changes in the chemical parameters of brine from 168 sampling points in the Mahai salt lake in the Qaidam Basin at three stages (before exploitation, during exploitation, and late exploitation) by correlation analysis, ion ratio analysis, and other methods and investigate the variations in porosity and the evolution laws of brine. The results show that the changes in the main ion content and brine mineralization during the exploitation process are small. The changes in Ca2+ content are significant due to the low solubility of calcium minerals, the precipitation of gypsum during the mixing process, and the adsorption of cations by alternating with Ca2+. Primary intergranular pore skeletons are easily corroded to form secondary pores, which increase the geological porosity. Na+ and Cl- are the dominant ions in the brine in the study area, but the concentration of Ca2 + decreased significantly under the influence of mining, by 41.7% in the middle period and 24.5% in the late period. The correlation between Ca2+ and salinity changes significantly in different mining stages, and the reason for the decrease of Ca2+ may be due to the influence of mineral dissolution, mixing, and anion-cation exchange. The porosity of the layer in the study area showed the opposite trend of Ca2+, and the porosity increased first and then decreased. The innovation of this paper lies in analyzing the reasons and mechanisms of the disturbance of artificial dissolution mining on stratum structure by comparing the hydrochemical characteristics and porosity of underground brine storage media in three different mining stages. The research in this paper provides a theoretical basis for the calculation of brine resource reserves and the sustainable development of underground brine in salt lake areas. [ABSTRACT FROM AUTHOR]

Building footprint maps are vital to many remote sensing (RS) applications, such as 3-D building modeling, urban planning, and disaster management. Due to the complexity of buildings, the accurate and reliable generation of the building footprint from RS imagery is still a challenging task. In this article, an end-to-end building footprint generation approach that integrates convolution neural network (CNN) and graph model is proposed. CNN serves as the feature extractor, while the graph model can take spatial correlation into consideration. Moreover, we propose to implement the feature pairwise conditional random field (FPCRF) as a graph model to preserve sharp boundaries and fine-grained segmentation. Experiments are conducted on four different data sets: 1) Planetscope satellite imagery of the cities of Munich, Paris, Rome, and Zurich; 2) ISPRS Benchmark data from the city of Potsdam; 3) Dstl Kaggle data set; and 4) Inria Aerial Image Labeling data of Austin, Chicago, Kitsap County, Western Tyrol, and Vienna. It is found that the proposed end-to-end building footprint generation framework with the FPCRF as the graph model can further improve the accuracy of building footprint generation by using only CNN, which is the current state of the art. [ABSTRACT FROM AUTHOR]

In order to more accurately identify multistage fracturing horizontal well (MFHW) parameters and address the heterogeneity of reservoirs and the randomness of well-production data, a new method based on the PSO-RBF neural network model is proposed. First, the GPU parallel program is used to calculate the bottomhole pressure of a multistage fracturing horizontal well. Second, most of the above pressure data are imported into the RBF neural network model for training. In the training process, the optimization function of the global optimal solution of the PSO algorithm is employed to optimize the parameters of the RBF neural network, and eventually, the required PSO-RBF neural network model is established. Third, the resulting neural network is tested using the remaining data. Finally, a field case of a multistage fracturing horizontal well is studied by using the presented PSO-RBF neural network model. The results show that in most cases, the proposed model performs better than other models, with the highest correlation coefficient, the lowest mean, and absolute error. This proves that the PSO-RBF neural network model can be applied effectively to horizontal well parameter identification. The proposed model has great potential to improve the prediction accuracy of reservoir physical parameters. [ABSTRACT FROM AUTHOR]

When the reservoir physical properties are distributed very dispersedly, the matching precision of these reservoir parameters is not good. We propose a novel method for matching the reservoir physical properties based on particle swarm optimization (PSO) and support vector machine (SVM) algorithm. First, the data structure characteristics of the reservoir physical properties are analyzed. Then, the particle swarm differential perturbation evolution algorithm is used to cluster and characterize the reservoir physical properties. Finally, by using the SVM algorithm for feature reorganization and the least squares matching of the extracted reservoir physical properties, the feature quantity of the reservoir physical properties can be accurately mined and the pressure matching precision is improved. The experimental results show that employing the proposed method to analyze and sample the data characteristics of the physical properties of the reservoir is better. The extracted parameters can effectively reflect the physical characteristics of oil reservoirs. The proposed method has potential applications in guiding the exploration and development of oil reservoirs. [ABSTRACT FROM AUTHOR]

Automatic building extraction from optical imagery remains a challenge due to, for example, the complexity of building shapes. Semantic segmentation is an efficient approach for this task. The latest development in deep convolutional neural networks (DCNNs) has made accurate pixel-level classification tasks possible. Yet one central issue remains: the precise delineation of boundaries. Deep architectures generally fail to produce fine-grained segmentation with accurate boundaries due to their progressive down-sampling. Hence, we introduce a generic framework to overcome the issue, integrating the graph convolutional network (GCN) and deep structured feature embedding (DSFE) into an end-to-end workflow. Furthermore, instead of using a classic graph convolutional neural network, we propose a gated graph convolutional network, which enables the refinement of weak and coarse semantic predictions to generate sharp borders and fine-grained pixel-level classification. Taking the semantic segmentation of building footprints as a practical example, we compared different feature embedding architectures and graph neural networks. Our proposed framework with the new GCN architecture outperforms state-of-the-art approaches. Although our main task in this work is building footprint extraction, the proposed method can be generally applied to other binary or multi-label segmentation tasks. [ABSTRACT FROM AUTHOR]

Purpose. To report the application of 14-MHz ultrasonography with tissue harmonic imaging (14 MHz + THI) to determine the integrity of the posterior capsule (PC) in traumatic cataract (TC). Methods. Patients with TC who were scheduled to undergo cataract extraction and whose PC could not be observed by slit lamp examination were included in the study. The status of the PC was determined by 14 MHz + THI before cataract extraction and confirmed during surgery. The results regarding PC integrity obtained from 14 MHz + THI and intraoperative direct observation were compared. Result. The study enrolled 52 eyes of 52 patients (49 men and 3 women), with a mean age of 42.15 years ± 11.23 (SD). The nature of the trauma was blunt (3 eyes) or sharp (49 eyes). The 14 MHz + THI method showed 21 PCs to be intact and 31 to have ruptured before cataract surgery. During surgery, 23 PCs were observed to be intact, while 29 PCs were ruptured. 27 PCs were ruptured and 19 were intact, as determined by the two methods. The 14 MHz + THI observations were consistent with the intraoperative observations of the PC (kappa = 0.764), with no significant difference between the two methods (P=0.687). The sensitivity, specificity, and accuracy of 14 MHz + THI for observation of the PC were 93.10%, 82.60%, and 88.46%, respectively. Conclusion. The 14 MHz + THI method can accurately reveal the integrity of the PC in TC. It has important clinical value in the selection of cataract surgery methods and the prediction of complications during TC surgery. [ABSTRACT FROM AUTHOR]

The direct-to-home satellite digital video broadcasting has been fast developed in the past decades, and the continuous phase modulation (CPM) is an alternative modulation scheme with the advantages of constant envelope and high spectral efficiency for the band-limited channel and non-linear amplifiers of the satellite transponder. In this paper, CPM cascaded with irregular low density parity check (LDPC) code is studied. A practical system model with global interleaving is proposed for the optimization of degree distribution of the LDPC codes, and code word design is obtained with a modified progressive edge-growth algorithm. Simulation results combined with theoretical analysis clarify the effect of signal-to-noise ratios and two important CPM parameters (modulation index ${h}$ and correlation length ${L}$ ), providing guidance for system design. Simulation on bit error rate performance show the validity of the proposed algorithm. This paper systematically solves the optimal system design of cascade irregular LDPC-CPM and is of great significance for future satellite broadcasting. [ABSTRACT FROM AUTHOR]

Electromagnetic interference has become one urgent problem in the current society. Efficient preparation of materials with excellent electromagnetic wave absorption is challenging but urgently needed. In this work, MnFe 2 O 4 /rGO/Diatomite (M/rGO/DT) cladding structure composites were prepared using a direct, one-step hydrothermal technique. The ternary composite has many microwave absorption mechanisms, including interfacial dipole polarization, conductive loss, natural resonance, flux loss, huge kudos to the three-dimensional cladding cross-linked structure and close-packed MnFe 2 O 4 particles. As a result, compared with unitary or binary composites this ternary composite offers superior capabilities in low and medium frequency microwave absorption. The composite's minimum reflection loss (RL min) is − 76.56 dB at 7.9 GHz, its thickness is 2.485 mm, and its effective absorption bandwidth (EAB) is up to 3.61 GHz. The remarkable electromagnetic wave attenuation ability of the generated ternary composite shows that the work in this research may provide an innovative and simple technique for the preparation of superior microwave absorbing materials (MAMs). • MnFe 2 O 4 /rGO/diatomite composite provides new possibilities for modifying ferrite wave absorbing materials. • This ternary composite offers superior capabilities in low and medium frequency microwave absorption. • Impedance matching and attenuation coefficient cooperatively regulate microwave absorption of composites. [ABSTRACT FROM AUTHOR]

Shale gas has now become an important part of unconventional hydrocarbon resources all around the world. The typical properties of shale gas are that both adsorbed gas and free gas play important roles in gas production. Thus the contributions of free and adsorbed gas to the shale gas production have become a hot, significant, and challenging problem in petroleum engineering. This paper presents a new analytical method to calculate the amounts of free and adsorbed gas in the process of shale gas extraction. First, the expressions of the amounts of adsorbed gas, matrix free gas, and fracture free gas in shale versus the producing time are presented on the basis of Langmuir adsorption model and formation pressure distribution. Next, the mathematical model of multifractured horizontal wells in shale gas reservoirs is established and solved by use of Laplace transform and inversion to obtain the normalized formation pressure distribution. Finally, field case studies of two multifractured horizontal shale gas wells in China are carried out with the presented quantitative method. The amounts of adsorbed and free gas in production are calculated, and the adsorbed-to-total ratio is provided. The results show that the proposed method is reliable and efficient. [ABSTRACT FROM AUTHOR]

A mathematical model for multistage hydraulically fractured horizontal wells (MFHWs) in tight oil and gas reservoirs was derived by considering the variations in the permeability and porosity of tight oil and gas reservoirs that depend on formation pressure and mixed fluid properties and introducing the pseudo-pressure; analytical solutions were presented using the Newman superposition principle. The CPU-GPU asynchronous computing model was designed based on the CUDA platform, and the analytic solution was decomposed into infinite summation and integral forms for parallel computation. Implementation of this algorithm on an Intel i5 4590 CPU and NVIDIA GT 730 GPU demonstrates that computation speed increased by almost 80 times, which meets the requirement for real-time calculation of the formation pressure of MFHWs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co/ZnO@CMWCNTs/Ti 3 C 2 T x composite exhibited hierarchically porous flower-like assembled with MXene nanosheet were prepared. • The minimum reflection loss of the composite is up to −46 dB at 1.5 mm. • The modulation of electromagnetic parameters was achieved by controlling the load of MXene. • Excellent performance comes from the effect of dielectric loss and magnetic loss. The design of a hierarchical three-dimensional (3D) structure is beneficial to suppressing the accumulation of MXene flakes and obtaining satisfactory lightweight, efficient, and broadband-absorbing materials. Undoubtedly, the exploration of electromagnetic wave (EMW) absorbing materials with stronger absorption and thinner thickness of multi-component and multi-mechanism synergy is in great demand, but it is still a challenge. In this paper, we report for the first time a well-designed and optimized electrostatic self-assembly anchored Ti 3 C 2 T x nanosheet to prepare porous flower-like Co/ZnO@CMWCNTs/Ti 3 C 2 T x (CZCT) composites. The electromagnetic parameters and EMW absorption properties of carboxylated multi-walled carbon nanotubes (CMWCNTs) and Ti 3 C 2 T x nanosheets can be controlled by adjusting the load of CMWCNTs and Ti 3 C 2 T x nanosheets. Based on the multi-dimensional material collaboration and electromagnetic synergistic strategy, the flower-like CZCT composite achieves a significant minimum reflection loss (RL min) of −46 dB at a thickness of 1.5 mm. The maximum effective absorption bandwidth (EAB max) of 4 GHz is 1.9 mm. This work provides a simple strategy for building MXene-based composites to achieve efficient EMW absorption materials with lightweight and adjustable EAB. [ABSTRACT FROM AUTHOR]

Aiming at the problem of distributed state estimation in sensor networks, a novel optimal distributed finite-time fusion filtering method based on dynamic communication weights has been developed. To tackle the fusion errors caused by incomplete node information in distributed sensor networks, the concept of limited iterations of global information aggregation was introduced, namely, fast finite-time convergence techniques. Firstly, a local filtering algorithm architecture was constructed to achieve fusion error convergence within a limited number of iterations. The maximum number of iterations was derived to be the diameter of the communication topology graph in the sensor network. Based on this, the matrix weight fusion was used to combine the local filtering results, thereby achieving optimal estimation in terms of minimum variance. Next, by introducing the generalized information quality (GIQ) calculation method and associating it with the local fusion result bias, the relative communication weights were obtained and embedded in the fusion algorithm. Finally, the effectiveness and feasibility of the proposed algorithm were validated through numerical simulations and experimental tests. [ABSTRACT FROM AUTHOR]

Recent years have witnessed major innovations in mobile crowdsourcing networks. For selfish participants, conventional methods resort to incentive mechanism design for resource utilization, which might overlook the inherent equilibrium property among mobile users. In contrast to these proposals, we investigate the problem that whether or not the selfish users could be enabled to endorse stable task sharing with balanced allocations without incentive mechanism designs. Before making a positive answer to this problem, we need to address the following challenge, i.e., users have to make their balancing decisions with only very limited and dynamic local load information, which could possibly incur longer convergence time and imbalanced task allocations. In tackling this difficulty, we propose two distributed selfish load balancing schemes, the max-weight best response policy for strong information scenario, where load information could be sufficiently collected; and the proportional allocation policy for weak information scenario. We make experimental studies to validate proposed schemes. In our simulation study with real trace data, the proposed schemes converge fast in many typical settings with fairly good balancing performance. As for data traces from RollerNet (Tournoux et al., The accordion phenomenon 2009), the performance of load balancing and convergence property are further validated. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the task offloading issue in mobile social networks. Although the “d-choice” paradigm in “ball and bin” theory had shown the power of random choice in load balancing with a random walk model, its performance could be fairly poor where real-trace data sets are concerned. According to our preliminary evaluation results with “MobiClique,” the “d-choice” scheme could not achieve well-balanced allocations in a real-trace data set. Nevertheless, it would bring fundamental challenges to task reassignment in the following aspects: First of all, some of the friendships are relatively stable, which would lead to a more imbalanced task assignment, even if the “d-choice” scheme is applied for balancing. Second, some users would meet quite infrequently, which could inevitably lead to intolerable time delay and unfair task allocations. In tackling these difficulties, we revisit the real data sets for exploring the contact property among users. We find that the frequently met users could be leveraged for efficient task execution due to higher task priority. To this end, we propose the “ $i$ Top-K” algorithm, leveraging the basic concept, i.e., “your friends are more powerful than you,” which encourages mobile users to assign tasks among intimate friends instead of pure random assignment. With careful selections of “Top-K” friends, we achieve balanced load and guaranteed performance at the same time. Experimental studies verify our scheme and show the effectiveness with three typical data trace sets, including “MobiClique.” In this typical networking scenario, ours outperforms the conventional random choice scheme up to 15 $\times$ and the social relationship assignment without priority method up to 9 $\times$. Moreover, the “Top-K” scheme could be adaptive, even when no intimate friends are available. By scaling the “K” factor to larger values, our scheme outperforms random assignment and could be inspiringly close to the optimal solution. In summary, ours could effectively explore the social relationship and leverage it for efficient task assignment, which would further encourage more mobile users to work together under the rule of social contacts. [ABSTRACT FROM AUTHOR]

• Transcriptome sequencing of the branches of 'Bartlett' and 'Red Bartlett'. • Weighted gene coexpression network analysis (WGCNA) identified 495 differentially expressed genes positively associated with anthocyanin. • The expression levels of one UFGT and one GST were also upregulated in the pericarps of 'Red Bartlett' and 'Starkrimson' than in 'Bartlett' and 'Clapps Favourite'. The color of the peel is the most direct reflection of fruit quality, and is also an important factor in attracting consumers. The 'Red Bartlett' pear (Pyrus communis L.) is a red bud sport mutant variety of 'Bartlett' pear. It was found that the anthocyanin content in branches and pericarps of 'Red Bartlett' pears were significantly higher than that of 'Bartlett' pears. The present study aimed to clarify the underlying mechanisms of anthocyanin accumulation in 'Red Bartlett' using a transcriptome analysis. A weighted gene coexpression network analysis (WGCNA) identified 495 differentially expressed genes positively associated with anthocyanin. Additionally, 12 anthocyanin-related structural genes and 13 transcription factors, including WRKY, ERF, bHLH, ASIL2, and HSF, were identified through screening of 495 DEGs. The expression levels of one UFGT (Pbr014258.1) and one GST (Pbr012649.1) were also upregulated in the pericarps of 'Red Bartlett' and 'Starkrimson', more so than in 'Bartlett' and 'Clapps Favourite'. Overall, this study clarified that the red color mutation of 'Red Bartlett' was closely linked to increased anthocyanin biosynthesis and transport. This study provided an abundance of valuable information on anthocyanin biosynthesis for future breeding of red-skinned pears. [ABSTRACT FROM AUTHOR]

The natural Leymus chinensis grassland in western Jilin Province of NE China has been extensively degraded, thereby restricting the development of animal husbandry. Using theory of ecological stoichiometry homeostasis, this study investigated the homeostasis of L. chinensis at different degradation stages in the research area using a homeostasis model. Results showed that the degraded grassland generally had lower soil carbon (C), nitrogen (N) and phosphorus (P) compared with normal L. chinensis grassland. In particular, the degraded grassland exhibited severe shortage of P, but L. chinensis showed strong homeostasis. Except for C in the roots and leaves and P in stems, the N, P and corresponding ratios had higher homeostasis than 1, between 1.53 and 15.92. The homeostasis of N in L. chinensis was higher than that of P, and the homeostasis of C/P was higher than that of C/N and N/P. L. chinensis absorbs and uses nutritive elements in a conservative manner, which enables it to remain productive during changes in the external environment. Therefore, grassland degradation control should prioritize the protection of dominant species. Appropriate use of N and P fertilizers is suggested for the recovery of the seriously degraded L. chinensis grassland ecosystem. [ABSTRACT FROM AUTHOR]

This paper is concerned with the estimation of correlated noise and packet dropout for information fusion in distributed sensing networks. By studying the problem of the correlation of correlated noise in sensor network information fusion, a matrix weight fusion method with a feedback structure is proposed to deal with the interrelationship between multi-sensor measurement noise and estimation noise, and the method can achieve optimal estimation in the sense of linear minimum variance. Based on this, a method is proposed using a predictor with a feedback structure to compensate for the current state quantity to deal with packet dropout that occurs during multi-sensor information fusion, which can reduce the covariance of the fusion results. Simulation results show that the algorithm can solve the problem of information fusion noise correlation and packet dropout in sensor networks, and effectively reduce the fusion covariance with feedback. [ABSTRACT FROM AUTHOR]

• The Single arm unbalanced bridge method is applied for insulation detection. • A digital filter and Kalman filter were used to filter out noise in the voltage signal. • The matching design of each parameter of the unbalanced bridge circuit and the use of a filtering algorithm were applied to improve the accuracy of insulation resistance measurements. In the DC system of electric ships, insulation drops and grounding will pose a threat to stable ship operation and personal safety. Therefore, it is necessary to monitor the insulation status of the battery pack between high voltage and ground in real time. However, traditional measurement methods have problems such as low accuracy, long measurement time, and poor reliability. In this paper, an insulation detection method based on an unbalanced bridge was proposed and the principle of insulation resistance detection was analyzed. The influence of different resistance values of insulation detection circuits on the measurement error of insulation resistance was studied by simulation analysis and experimental tests to obtain the optimal set of bridge resistance matching designs. Digital filter and Kalman filter were used to filter out noise in the voltage signal. The results show that measurement error of insulation resistance after optimization was less than 3% and drops to approximately 0.46% after processing by the Kalman filter algorithm, which proves that the insulation detection method designed in this paper has high measurement accuracy. [ABSTRACT FROM AUTHOR]

• Hollow carbon cavities decorated with highly dispersed Mn-N moieties were developed. • The hollow carbon cavities endowed the developed Mn-NC with considerable ORR catalytic activity in both alkaline and neutral electrolyte. • The Mn-NC-driven ZAB and MAB exhibited impressive discharge performance than those driven by commercial Pt/C catalyst. The designed synthesis of hollow carbon chamber catalysts is central for accelerating the oxygen reduction reaction (ORR) electrocatalysis, which is the core process of renewable metal-air batteries. Nevertheless the positive effect of hollow carbon cavities on the actual ORR electrocatalysis in alkaline and neutral medium is still underexplored. Herein, manganese-decorated zeolite imidazolate frameworks coated with polydopamine (PDA) was pyrolyzed to form the hollow and macroporous carbon cavities decorated with highly dispersed manganese-nitrogen moieties (Mn-NC). The hollow carbon cavities with spacious microchemical environment can maximize the amount of atomically active sites and provide convenient mass transfer channels, cooperatively boosting the alkaline and neutral ORR via an efficient close to four-electron pathway. As result, the hollow Mn-NC exhibited much enhanced catalytic capability than Mn-C synthesized without polydopamine coating in both alkaline and neutral electrolyte. When utilized as a cathode catalyst, the homemade zinc-air battery (ZAB) and magnesium-air battery (MAB) driven by Mn-NC displayed higher peak power density and longer stable discharge time than those driven by commercial Pt/C catalyst, along with robust rate performance, showing appreciable application potential. This work may inspire more study on rational design and synthesis of hollow catalysts with boosted ORR electrocatalysis for efficient energy conversion devices including fuel cells and other metal-air batteries and beyond. [Display omitted] [ABSTRACT FROM AUTHOR]

The two major problems with Hall thrusters are the sputtering erosion of the discharge channel wall and the low-frequency oscillation. A new design for a Hall thruster with an innovative buffer chamber, in which part of the propellant is ionized, shows effective ability to restrain the low-frequency oscillation. However, how the preionization affects the erosion of the channel wall has not been well studied. In this paper, a 2-D axisymmetric fully kinetic particle-in-cell and Monte Carlo collision model is developed to investigate the effect of preionization on erosion of the channel wall of a Hall thruster. The geometry of this simulation model corresponds to the typical SPT-70 thruster, and the computational domain includes the whole discharge chamber of the thruster and the near-field plume region. Some scaling laws are introduced to accelerate this simulation. A preionization model and an erosion model are imported into the simulation to investigate the effect of different preionization ratios on the erosion of the channel wall. The results indicate that the effect of preionization on the change in the electric field is not obvious, in that it does not change the energy of the sputter ions significantly. When the preionization ratio increases, the ion incidence angle decreases slightly, but the number of sputter ions increases markedly. Overall, the erosion of the channel wall increases with the increasing preionization ratio. It needs further consideration for the application of the buffer chamber that preionizes the discharge plasma. [ABSTRACT FROM PUBLISHER]

Fracture-caved carbonate reservoirs (FCCRs) have been developed worldwide and contribute significantly to world's hydrocarbon reserves. Numerous models for FCCRs were proposed in the previous works. However, with more and more exploitations, some kinds of FCCRs are observed from the field geological information but not reported in the existing literature. In this paper, a novel model for FCCRs is proposed and its corresponding pressure transient analysis (PTA) and rate transient analysis (RTA) solutions are presented. This model has a wider applicability than the previous models proposed by our research team. First, the geological model is established based on the geological information. Sequentially, the simplified physical model and the mathematical model are developed. Through Laplace transformation, Duhamel's principle, and Stehfest numerical inversion, the solutions of dimensionless bottom-hole pressure and dimensionless flow rate integral are derived. Then, the RTA type curves of two-cave model are plotted to recognize the flow characteristics, which can be divided into five regimes comprehensively. In addition, two concaves are observed on the derivative curve. The RTA type curves of three-cave model are also presented. A comparison between the RTA type curves of two-cave model and three-cave model shows that when one more cave exists in the formation, one more concave will be added to the derivative curve. Furthermore, the differences between the proposed model and previous models are presented through comparing the PTA type curves. Next, the effects of key parameters on the RTA curve behavior of two-cave model are demonstrated. Results indicate that the RTA curves are controlled by the friction and fluctuation coefficients, mobility, storage ratio, region radius, and cave storage constant. The friction and fluctuation coefficients influence the depth of first concave, while the storage ratio, region radius, and cave storage constant dominate the middle flow period, and the mobility has an impact on the boundary dominated flow regime. Finally, the application of proposed model on a field well from Shunbei Oilfield, western China is presented to calibrate its accuracy and reliability. ∙ A novel model for fracture-caved carbonate reservoirs is established. ∙The rate transient characteristics of this model is conducted. ∙Sensitivity studies of some key parameters on the pressure response are conducted. ∙An application of proposed model on a field well is presented. [ABSTRACT FROM AUTHOR]

Abstract: Many diatoms form resting stages under adverse growth conditions. These resting stages are known to rejuvenate once favorable conditions return, and resume vegetative growth after a certain lag period in which no divisions occurred, but what happens during this period remains unclear. Nitrogen uptake and the accumulation of free amino acids in Skeletonema marinoi resting cells during rejuvenation, but before cell division, were studied in laboratory cultures at different light intensities using the 15N-tracer technique. N uptake rate was higher for the rejuvenating cells at the higher light intensity. We hypothesized that the rapid and increasing N uptake at higher irradiance could enable S. marinoi to rebuild and reorganize its cell contents quickly and so dominate subsequent vegetative growth on the surficial sediment. Compared to the logarithmic growth phase and stationary phase, much higher concentrations of glycine (Gly) and histidine (His) were detected in resting cells, and His appeared to be a storage compound in S. marinoi resting cells. Compared to glutamine, glutamate had the higher 15N label enrichment under the light condition, showing a diel variation of N status during the lag period. The 15N labeled urea was detected at 36h, compared to the urea cycle intermediates ornithine and citrulline at 30h, indicating that urea was produced as an N reservoir due to the higher nitrogen uptake in the dark, and that the urea cycle was involved in S. marinoi resting cell rejuvenation. [Copyright &y& Elsevier]

Shale gas reservoirs contribute significantly to hydrocarbon production because of their abundant reserves. Shale formation is characterized by low permeability and extremely low porosity. Horizontal well drilling and hydraulic fracturing treatments are typical methods for stimulating the shale gas reservoirs. The discrete fracture model has been widely used to describe flow problems in fractured media. Rock deformation is an important process that occurs simultaneously with the gas flow during the production period and cannot be neglected when modeling the gas flow in shale formations. The matrix permeability, matrix porosity, fracture permeability, and fracture aperture are all considered pressure-dependent parameters when accounting for rock deformation. Two inadequacies exist in previous studies on modeling shale gas flow in deformable rock. One is determining the values of pressure-dependent parameters using an explicit method, which means that the pressure-dependent parameters in the next time step are calculated according to the pore pressure of the last time step and remain constant in the iterative solving process of the next time step. During the production, the pore pressure always decreasing, which leads to compression in fractures and a reduction in the fracture permeability and aperture. The explicit method inevitably causes an overestimation of the reservoir productivity. Another inadequacy is neglecting the effect of the change in fracture geometry. In this paper, a fully implicit and fully coupled numerical scheme for discrete fracture modeling of shale gas flow in deformable rock is proposed to reduce the computational error. A comparison between the results of no rock deformation, an explicit method, and implicit method and a field example are presented to calibrate the accuracy of proposed scheme. Another comparison between the explicit and implicit methods shows that the implicit method can noticeably reduce the overestimation caused by the explicit method. The effects of the controlling parameters on the relative difference between the explicit and implicit methods are demonstrated. The results show that the initial permeability of the hydraulic fracture has negligible influence on the relative difference. The initial permeability and compression coefficient of the natural fracture are the main influencing parameters, the initial matrix permeability has a limited impact on the relative difference. The relative difference is caused by the comprehensive effect of k ij and (A / d) ij terms. • A fully implicit and fully coupled numerical scheme for DFM is proposed. • The numerical scheme is derived in detail. • The comparison between the explicit and implicit methods are presented. • Sensitivity study of key parameters on the relative difference are conducted. [ABSTRACT FROM AUTHOR]

The radial migration of neuronal progenitor cells is critical for the development of cerebral cortex layers. They go through a critical step transforming from multipolar to bipolar before outward migration. A Disintegrin and Metalloprotease 17 (ADAM17) is a transmembrane protease which can process many substrates involved in cell-cell interaction, including Notch, ligands of EGFR, and some cell adhesion molecules. In this study, we used in utero electroporation to knock down or overexpress ADAM17 at embryonic day 14.5 (E14.5) in neuronal progenitor cells to examine the role of ADAM17 in cortical embryonic neurogenesis. Our results showed that the radial migration of ADAM17-knocked down cells were normal till E16.5 and reached the intermediate zone (IZ). Then most transfected cells stopped migration and stayed at the IZ to inner cortical plate (CP) layer at E18.5, and there was higher percentage of multipolar cells at IZ layer in the ADAM17-knocked down group compared to the cells in control group. Marker staining revealed that those ADAM17-knocked down cells differentiated normally from neural stem cells (NSCs) to neuronal intermediate progenitor cells (nIPCs) but did not differentiate into mature neurons. The migration and multipolar exit defects caused by ADAM17 knockdown could be partially rescued by over-expressing an shRNA resistant ADAM17, while overexpressing ADAM17 alone did not affect the radial migration. Taken together, our results showed for the first time that, ADAM17 is critical in regulating the multipolar-stage exit and radial migration of the nIPCs during telencephalon cortex development in mice. [ABSTRACT FROM AUTHOR]

Abstract: Three-dimensional porous Sn thin film electrodes were prepared by electroless deposition on copper foam, then its morphology and electrochemical property were studied by means of scanning electron microscope (SEM), X-ray diffraction (XRD), electrochemical cycling test and cyclic voltammetry (CV). The porous framework and micro-holes have shown a great structure advantage in restricting severe volume changes when the Sn thin film was employed as anode for lithium-ion battery. The film electrode of sample C with an initial capacity of 676mAhg−1 showed good cycle performance displayed by retaining a capacity of 313mAhg−1 after 100 cycles. [Copyright &y& Elsevier]

In this paper, we consider blind source separation/channel equalization problems for an unknown nonlinear channel. By using the property of the binary alphabets, we show that blind nonlinear source separation/channel equalization problems can be easily solved by existing linear methods. [ABSTRACT FROM AUTHOR]

Presents information on a study which proposed a blind channel equalization at symbol baud rates assuming that the constellation alphabet is known. Problem formulation; Algorithm for solving the blind channel equalization problem; Conclusions.

Soil/sediment samples of four different land types were collected from aquaculture land, farmland, industrial land and river bottom sediment in the estuary area of Dagu River. The contents of Cr, Cu, Zn, As, Cd and Pb in 0–30 cm inner surface samples were detected, and the distribution characteristics of heavy metal content in surface soil/sediment of different land use types in the estuary area were analyzed. Local accumulation index method, potential risk index evaluation method and principal component analysis method were used to analyze the pollution status and sources of heavy metals. The results showed that the heavy metal accumulation levels in soil and sediment samples in the study area were As > Cd > Cu > Pb > Zn > Cr, and the heavy metal content exceeded the soil background value in Shandong Province, but the potential risks were all in a low risk state. The main sources of Cr, Zn and As are transportation sources and natural sources, while the main sources of Cd and Pb are agricultural. • TOC is not strongly correlated with the distribution and origin of heavy metals • The risk of heavy metal pollution in the estuary of Dagu River is low • The factor load of Cu is the highest, and Cu pollution may be caused by transportation, industrial activities and agricultural activities [ABSTRACT FROM AUTHOR]

[Display omitted] Metal sulfides (MSs) have attracted much attention as anode materials for sodium-ion batteries (SIBs) due to their high sodium storage capacity. However, the unsatisfactory electrochemical performance induced by the huge volume change and sluggish kinetics hampered the practical application of SIBs. Herein, guided by the heterostructure interface engineering, novel multicomponent metal sulfide-based anodes, including SnS, FeS, and Fe 3 N embedded in N -doped carbon nanosheets (SnS/FeS/Fe 3 N/NC NSs), have been synthesized for high-performance SIBs. The as-prepared SnS/FeS/Fe 3 N/NC NSs with abundant heterointerfaces and high conductivity of N -doped carbon nanosheet matrix can shorten the Na+ diffusion path and promote reaction kinetics during the sodiation/desodiation process. Moreover, the presence of Fe 3 N can promote the reversible conversion of SnS and FeS during the cycling process. As a consequence, when evaluated as anode materials for SIBs, the SnS/FeS/Fe 3 N/NC NSs can maintain a high sodium storage capacity of 473.6 mAh g-1 after 600 cycles at 2.0 A g-1 and can still provide a high reversible capacity of 537.4 mAh g-1 even at 5.0 A g-1 This discovery offers a novel strategy for constructing metal sulfide-based anode materials for high-performance SIBs. [ABSTRACT FROM AUTHOR]