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As a promising material for marine engineering, the insufficient corrosion resistance of manganese aluminium bronze (MAB) alloy when exposed to the marine environment may limit its application. In the present work, micro-arc oxidation (MAO) of MAB alloy was conducted in an aluminate-based electrolyte with the influence of ultrasonic vibration (UV) examined. A porous ceramic film has been successfully produced on MAB via MAO, which exhibits dramatic increases in both film thickness and compactness after the introduction of UV. As a result, the ceramic film produced by ultrasound-assisted MAO (UMAO) exhibits an enhanced corrosion resistance relative to that via MAO, which also possesses a desired antifouling capability. Hence, the present work illustrates the influence of UV on the MAO behaviour of non-valve alloys and, more importantly, provides theoretical guidance for related surface modification strategies in marine engineering.

Abstract A broad consensus of neutralizing the carbon dioxide emissions facilitates the transition to the renewable energy power system. Meanwhile, the concerns about the volatility of renewable energies are growing as the rotational inertia of power system becomes inadequate. To maintain the frequency stability of power system, some studies for configuring inertia energy storage systems (ESSs) are carried out, mainly focusing on the allocation of virtual inertia from grid‐forming ESS. In contrast, the allocation of virtual inertia from grid‐following ESS has not been well elaborated and the differences in virtual inertia provided by these two modes are yet to be revealed. Based on H2‐norm and Kron reduction, firstly, the state‐space model of post‐disturbance system is established, together with the transient performance evaluation. Then the inertia characteristics of both grid‐forming and grid‐following devices are formulated, followed by the unified gradient descent optimization method for allocating virtual inertia. A modified IEEE 39‐bus system and its time‐domain simulations help in the verification of the contribution of this paper. Through the comparative analysis of corresponding optimal results, the conclusions from two aspects are drawn: in terms of transient frequency support, the grid‐forming devices can provide no less than 26% better inertia support; with the higher power capacity and similar energy capacity, the grid‐forming devices can relieve the response pressure of other generators by approximately 77.1%.

Abstract Neural crest cells (NCCs) are central to vertebrate embryonic development, giving rise to diverse cell types with unique migratory and differentiation capacities. This study examines the molecular characteristics of cranial neural crest cell (CNCC)-derived mesenchymal cells, specifically those from teeth which in deer show continuous but limited growth, and antlers, which exhibit remarkable regenerative capabilities. Here, through single-cell RNA sequencing analysis, we uncover shared gene expression profiles between adult antlerogenic and dental mesenchymal cells, indicating common developmental pathways. We identify a striking resemblance in transcriptomic features between antlerogenic progenitor cells and dental pulp mesenchymal cells. Comparative analysis of CNCC-derived and non-CNCC-derived mesenchymal cell pools across species reveals core signature genes associated with CNCCs and their derivatives, delineating essential connections between CNCCs and CNCC-derived adult mesenchymal pools. Furthermore, whole-genome DNA methylation analysis unveils hypomethylation of CNCC derivate signature genes in regenerative antlerogenic periosteum, implying a role in maintaining multipotency. These findings offer crucial insights into the developmental biology and regenerative potential of CNCC-derived mesenchymal cells, laying a foundation for innovative therapeutic strategies in tissue regeneration.

Phasor Measurement Units (PMUs) are widely used in power system state estimation due to its high sampling rate and real-time estimation of power state in power systems. However, it is also vulnerable to cyberattacks (GPS spoofing attacks) since it uses unencrypted GPS civil signals for synchronization. The GPS spoofing attacks (GSAs) will intentionally manipulate the time reference of PMUs, which is equivalent to falsifying the phase angle of the PMU measurements. In this paper, we consider the secure power state estimation and attacks detection with the unknown GSAs in the power systems. Particularly, we derived the PMU-based GSAs model in the power state estimation problem, which is formulated as a mixed maximum likelihood problem. In the formulated problem, the involved unknown parameters are coupled and the objective function is non-convex, which are of significant challenges in finding optimal solutions. To tackle these challenges, a joint maximum a posteriori and maximum likelihood (JMAP-ML) algorithm is proposed to securely estimate the power state and detect the GSAs in the mixed measurements of PMUs. Different testing scenarios in IEEE 14 bus system are simulated to show the proposed algorithm’ performance on GSAs detection and state estimation. Numerical examples demonstrate the improved accuracy of our algorithm compared with classical algorithms when GSAs are present. And we conclude that when a sufficient number of PMUs are deployed in the system, the impact of GSAs will be largely compensated in the estimation stage.

Nitrite-oxidizing bacteria (NOB) are undesirable in the anaerobic ammonium oxidation (anammox)-driven nitrogen removal technologies in the modern wastewater treatment plants (WWTPs). Diverse strategies have been developed to suppress NOB based on their physiological properties that we have understood. But our knowledge of the diversity and mechanisms employed by NOB for survival in the modern WWTPs remains limited. Here, Three NOB species (NOB01–03) were recovered from the metagenomic datasets of a full-scale WWTP treating duck breeding wastewater. Among them, NOB01 and NOB02 were classified as newly identified lineage VII, tentatively named Candidatus (Ca.) Nitrospira NOB01 and Ca. Nitrospira NOB02. Analyses of genomes and in situ transcriptomes revealed that these two novel NOB were active and showed a high metabolic versatility. The transcriptional activity of Ca. Nitrospira could be detected in all tanks with quite different dissolved oxygen (DO) (0.01–5.01 mg/L), illustrating Ca. Nitrospira can survive in fluctuating DO conditions. The much lower Ca. Nitrospira abundance on the anammox bacteria-enriched sponge carrier likely originated from the intensification substrate (NO2−) competition from anammox and denitrifying bacteria. In particular, a highlight is that Ca. Nitrospira encoded and treanscribed cyanate hydratase (CynS), amine oxidase, urease (UreC), and copper-containing nitrite reductase (NirK) related to ammonium and NO production, driving NOB to interact with the co-existed AOB and anammox bacteria. Ca. Nitrospira strains NOB01 and NOB02 showed quite different niche preference in the same aerobic tank, which dominanted the NOB communities in activated sludge and biofilm, respectively. In addition to the common rTCA cycle for CO2 fixation, a reductive glycine pathway (RGP) was encoded and transcribed by NOB02 likely for CO2 fixation purpose. Additionally, a 3b group hydrogenase and respiratory nitrate reductase were uniquely encoded and transcribed by NOB02, which likely confer a survival advantage to this strain in the fluctuant activated sludge niche. The discovery of this new genus significantly broadens our understanding of the ecophysiology of NOB. Furthermore, the impressive metabolic versatility of the novel NOB revealed in this study advances our understanding of the survival strategy of NOB and provides valuable insight for suppressing NOB in the anammox-based WWTP.

Abstract Improving the absorption of electromagnetic waves at low-frequency bands (2-8 GHz) is crucial for the increasing electromagnetic (EM) pollution brought about by the innovation of the fifth generation (5G) communication technology. However, the poor impedance matching and intrinsic attenuation of material in low-frequency bands hinders the development of low-frequency electromagnetic wave absorbing (EMWA) materials. Here we propose an interface-induced dual-pinning mechanism and establish a magnetoelectric bias interface by constructing bilayer core-shell structures of NiFe2O4 (NFO)@BiFeO3 (BFO)@polypyrrole (PPy). Such heterogeneous interface could induce distinct magnetic pinning of the magnetic moment in the ferromagnetic NFO and dielectric pinning of the dipole rotation in PPy. The establishment of the dual-pinning effect resulted in optimized impedance and enhanced attenuation at low-frequency bands, leading to better EMWA performance. The minimum reflection loss (RLmin) at thickness of 4.43 mm reaches -65.30 dB (the optimal absorption efficiency of 99.99997%), and the effective absorption bandwidth (EAB) can almost cover C-band (4.72 ~ 7.04 GHz) with low filling of 15.0 wt.%. This work proposes a mechanism to optimize low-frequency impedance matching with electromagnetic wave (EMW) loss and pave an avenue for the research of high-performance low-frequency absorbers.

Abstract During growth phase, antlers exhibit a very rapid rate of chondrogenesis. The antler is formed from its growth center reserve mesenchyme (RM) cells, which have been found to be the derivatives of paired related homeobox 1 (Prrx1)-positive periosteal cells. However, the underlying mechanism that drives rapid chondrogenesis is not known. Herein, the miRNA expression profiles and chromatin states of three tissue layers (RM, precartilage, and cartilage) at different stages of differentiation within the antler growth center were analyzed by RNA-sequencing and ATAC-sequencing. We found that miR-140-3p was the miRNA that exhibited the greatest degree of upregulation in the rapidly growing antler, increasing from the RM to the cartilage layer. We also showed that Prrx1 was a key upstream regulator of miR-140-3p, which firmly confirmed by Prrx1 CUT&Tag sequencing of RM cells. Through multiple approaches (three-dimensional chondrogenic culture and xenogeneic antler model), we demonstrated that Prrx1 and miR-140-3p functioned as reciprocal negative feedback in the antler growth center, and downregulating PRRX1/upregulating miR-140-3p promoted rapid chondrogenesis of RM cells and xenogeneic antler. Thus, we conclude that the reciprocal negative feedback between Prrx1 and miR-140-3p is essential for balancing mesenchymal proliferation and chondrogenic differentiation in the regenerating antler. We further propose that the mechanism underlying chondrogenesis in the regenerating antler would provide a reference for helping understand the regulation of human cartilage regeneration and repair.

CM247LC, a Ni-based superalloy widely used in the aerospace industry due to its exceptional high-temperature performance, faces severe cracking issues in laser powder bed fusion (L-PBF) processing. This study investigates the effects of removing Hf and reducing Al content on the cracking and mechanical behaviors of LPBF-processed CM247LC. Microstructure characterization and thermodynamic calculation reveal that removing Hf narrows the solidification interval, reduces the fraction and size of inter-dendritic MC carbides, and thereby lowers its susceptibility to hot cracking. Decreasing Al content reduces the fraction and size of the γ'/γ eutectic phase and γ′ phase, alleviates local stress concentration, and enhances resistance to solid-state cracking. After chemical modification, the alloy exhibits a remarkable 96% reduction in crack density, a 75% reduction in crack length, and an 86% reduction in porosity, but displays comparable or even higher mechanical properties compared to LPBF-processed CM247LC. The effects of composition modification on the distribution of other elements, the precipitation of MC carbides and γ′ phase, the formation of annealed twins, the room and high temperature strength and ductility, are analyzed in detail. This study demonstrates that conventionally designed alloys can be adapted to the L-PBF process through compositional modification, achieving reduced defects and retained mechanical properties. The findings in this work are also instructive for alloy design tailored for the L-PBF process.

In today’s information age, eavesdropping has been one of the most serious privacy threats in information security, such as exodus spyware (Rudie et al., 2021) and pegasus spyware (Anatolyevich, 2020). And the main one of them is acoustic eavesdropping. Acoustic eavesdropping (George and Sagayarajan, 2023) is a technology that uses microphones, sensors, or other devices to collect and process sound signals and convert them into readable information. Although much research has been done in this area, there is still a lack of comprehensive investigation into the timeliness of this technology, given the continuous advancement of technology and the rapid development of eavesdropping methods. In this article, we have given a selective overview of acoustic eavesdropping, focusing on the methods of acoustic eavesdropping. More specifically, we divide acoustic eavesdropping into three categories: motion sensor-based acoustic eavesdropping, optical sensor-based acoustic eavesdropping, and RF-based acoustic eavesdropping. Within these three representative frameworks, we review the results of acoustic eavesdropping according to the type of equipment they use and the physical principles of each. Secondly, we also introduce several important but challenging applications of these acoustic eavesdropping methods. In addition, we compared the systems that meet the requirements of acoustic eavesdropping in real-world scenarios from multiple perspectives, including whether they are non-intrusive, whether they can achieve unconstrained word eavesdropping, and whether they use machine learning, etc. The general template of our article is as follows: firstly, we systematically review and classify the existing eavesdropping technologies, elaborate on their working mechanisms, and give corresponding formulas. Then, these eavesdropping methods were compared and analyzed, and each method’s effectiveness and technical difficulty were evaluated from multiple dimensions. In addition to an assessment of the current state of the field, we discuss the current shortcomings and challenges and give a fruitful direction for the future of acoustic eavesdropping research. We hope to continue to inspire researchers in this direction.

Fugu (Takifugu rubripes) is a commercially important fish in aquaculture in China, Japan, and Korea. Male fugu are highly prized compared to females because the mature testes are regarded as a delicacy, thus all-male populations are preferred in aquaculture. However, the molecular mechanisms underlying sex differentiation in fugu remain largely unclear. Progestins, which are mediated by the progesterone receptor, can initiate spermatogenesis or ovarian differentiation in teleosts. To explore the effect of progestin blockage on fugu sex differentiation, the antiprogestin mifepristone (RU486) (500 μg/g of feed) was administrated to fugu larvae from 30 to 90 days after hatching (dah). Histological analysis revealed that RU486 treatment resulted in complete masculinization (100 %) of the XX fugu population at both 120 (RU486 withdrawal 30 days) and 150 (RU486 withdrawal 60 days) dah, and RU486-treated XX gonads developed testes-like structure. Gonadal transcriptomic analysis at 90 dah identified 3595 genes that were differentially expressed (DEGs) between the control and treated groups. Among them, the expression of steroid hormone biosynthesis-related genes (e.g., cyp11c1, cyp19a1a, and hsd17b1) and other key genes (e.g., gsdf, dmrt1, and foxl2) were altered in the gonads of RU486-treated groups. Most of the DEGs were enriched in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to sex differentiation, such as neuroactive ligand-receptor interaction, ovarian steroidogenesis, and steroid hormone biosynthesis pathways. The expression of cyp19a1a, foxl2, cyp11c1, gsdf, dmrt3, and dmrt1 at 50, 70, and 90 dah was further assessed. The expression levels of gsdf, dmrt1, and cyp11c1 were increased, and the expression levels of cyp19a1a and foxl2 were decreased in the gonads of XX larvae in RU486 treated groups. These results demonstrated for the first time that RU486 induced masculinization in XX fugu and provided a theoretical basis for further studies of the regulatory role of progestins in sex differentiation in teleosts.

Representative large models and their related applications, such as Bidirectional encoder representations from transformers (BERT), Generative pretrained transformer (GPT), Segment anything model (SAM), ChatGPT, DALL-E, Wenxin, and Pangu, have made astounding strides and exerted considerable influence across various fields domestically and abroad. They constantly attract the attention and follow-up of diverse societal sectors, including enterprises, universities, and research institutions. Large model applications have been successfully applied in scenarios such as biology, medicine, law, and social governance. Designing, modifying, and constructing domain-specific large models are crucial for truly harnessing their application value. Therefore, this paper provides inspiration for the application of large models in materials science. First, it provides an overview of large models, introducing their basic concepts, developmental process, technical classification, and features. Second, from the perspectives of the general domain and specific large models, this paper summarizes the applications of large models and analyzes the application scenarios and functions of various types of large models. Subsequently, considering the specific needs and current state of research in the field of materials science, this paper reviews the application of large language models, large visual models, and large multimodal models. It integrates engineering strategies and zero-shot knowledge transfer learning from specific tasks in natural language processing and computer vision and referencing typical application cases, clarifying current research paradigms and limiting factors for applying large models to materials science. To verify the effectiveness and potential of the visual large model, basal experiments of image segmentation and key structure extraction are performed on the microscopic image data of four types of materials using improved SAM, including Ni-superalloy, superalloy, polycrystalline pure iron grain, and Inconel 939. The experimental results reveal that the zero-shot segmentation capability of SAM has enormous potential for accurate and efficient representation of material microstructures. With the help of tailored prompt engineering, precise masks of the precipitated phase, grain boundaries, and cracks can be outputted without any label. Finally, this paper proposes future research opportunities for technologies and methods related to large models in materials science. This paper assesses the feasibility and technical challenges for the development and tuning of unimodal to comprehensive multimodal large models. With continuous innovations and collaborations, the horizon for large models in materials science seems boundlessly promising. The integration of these models can produce a new era of advanced research, leading to advancements that were previously considered unattainable. The symbiosis between materials science and large models can pave the way for unforeseen discoveries, enriching our scientific prowess.

Highlights Feedback-regulation system is established between single Pt sites and MoS2 supports The Pt1-MoS2-def can expand the electron transfer path from single Pt sites to whole Pt-MoS2 supports in SO2 gas atmosphere. The Pt1-MoS2-def sensors exhibit high SO2 responses and extremely low limit of detection (3.14% to 500 ppb SO2) at room temperature. The Pt1-MoS2-def sensors array can realize real-time monitoring of SO2 for plant growth.

The microstructural changes in secondary carbides during spheroidized annealing (SA) and quenching and tempering (QT) processes in 60Cr16MoMA martensitic stainless steel has been comprehensively studied. Using scanning electron microscope, X-ray diffraction, inductively coupled plasma-atomic emission spectrometry, and transmission electron microscopy, a substantial dissolution of submicron-sized M23C6 carbides after QT treatment was observed, leading to an increase in the mean carbides diameter. The highest solubility occurs at a 0.5 μm diameter, and carbide roundness improves during QT. Notably, the transformation of M7C3 carbides into M23C6 carbides was observed in QT samples through a multi-site in-situ nucleation mechanism. Additionally, it has been observed that Nb-rich MC carbides effectively restrict the growth of alloy carbides during heat treatment.

Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of cardiovascular mortality and is increasingly prevalent in our population. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) can safely and effectively lower glucose levels while concurrently managing the full spectrum of ASCVD risk factors and improving patients’ long-term prognosis. Several cardiovascular outcome trials (CVOTs) have been carried out to further investigate the cardiovascular benefits of GLP-1RAs. Analyzing data from CVOTs can provide insights into the pathophysiologic mechanisms by which GLP-1RAs are linked to ASCVD and define the use of GLP-1RAs in clinical practice. Here, we discussed various mechanisms hypothesized in previous animal and preclinical human studies, including blockade of the production of adhesion molecules and inflammatory factors, induction of endothelial cells’ synthesis of nitric oxide, protection of mitochondrial function and restriction of oxidative stress, suppression of NOD-like receptor thermal protein domain associated protein three inflammasome, reduction of foam cell formation and macrophage inflammation, and amelioration of vascular smooth muscle cell dysfunction, to help explain the cardiovascular benefits of GLP-1RAs in CVOTs. This paper provides an overview of the clinical research, molecular processes, and possible therapeutic applications of GLP-1RAs in ASCVD, while also addressing current limitations in the literature and suggesting future research directions.

With the prevalence of various sensors and smart devices in people’s daily lives, numerous types of information are being sensed. While using such information provides critical and convenient services, we are gradually exposing every piece of our behavior and activities. Researchers are aware of the privacy risks and have been working on preserving privacy while sensing human activities. This survey reviews existing studies on privacy-preserving human activity sensing. We first introduce the sensors and captured private information related to human activities. We then propose a taxonomy to structure the methods for preserving private information from two aspects: individual and collaborative activity sensing. For each of the two aspects, the methods are classified into three levels: signal, algorithm, and system. Finally, we discuss the open challenges and provide future directions.

Abstract Reserve mesenchyme cells (RMCs) of deer antlers have been considered as the promising cell source for repairing injury‐induced articular cartilage or cartilage degeneration. However, systematic investigation of RMC differentiation to repair injured cartilage and its combination with biomaterials has not been reported. The aim of this study was to evaluate the role of RMCs in combination with hyaluronic acid (HA) in promoting chondrogenic differentiation through simulating native environments and their efficacy in articular cartilage repair. The RMCs were cultured in vitro for the characterization of these cells, including morphology, surface marker expression, and multipotent differentiation potential (adipogenesis, chondrogenesis, and osteogenesis). When combined with HA in vitro, RMCs increased expression levels of the chondrogenic marker gene (COL II and COMP) but decreased levels of the hypertrophic marker gene (COL X). Using a rat articular cartilage defect model, we evaluated the effects of RMCs in combination with HA on cartilage defect repair at 4 and 8 weeks through macroscopical, histological, and immunohistochemical examinations. Compared with other groups, treatment with RMCs + HA reduced cartilage loss and degree of cartilage surface worn, whereas cartilage content was significantly increased. These results suggest that the combination of RMCs with HA can effectively repair cartilage defects. We believe that effective cartilage defect repair will benefit from the use of RMCs together with favorable biomaterials, such as HA.

Abstract Pulmonary fibrosis (PF), a chronic interstitial lung disease, is characterized by over-abundant deposition of extracellular matrix consisting mainly of collagen I. In previous studies, we demonstrated that deer antler stem cells (AnSCs), a novel type of adult stem cell, are capable of significantly down-regulating collagen formation in different organs and tissues and speculated that they could effectively treat PF via reducing collagen deposition in the lung tissue. In the present study, we found that administration of AnSCs improved the survival rate of PF mice and reduced lung fibrosis, collagen deposition and myofibroblast differentiation. The effects of AnSC treatment were significantly better than the positive control (adipose-derived stem cells). Interestingly, AnSC-Exos were almost equally effective as AnSCs in treating PF, suggesting that the effects of AnSCs on reduction of PF may be mainly through a paracrine mechanism. Further, AnSC-Exos reduced the number of M2 macrophages, a type of macrophage that secrets pro-fibrotic factors to accelerate fibrotic progression, in the lung tissues. In vitro experiments showed that the effects of AnSC-Exos on macrophage modulation were likely achieved via inhibition of the recruitment of circulating monocyte-derived macrophages (reducing the number of macrophages), rather than via inhibition of M2 polarization of macrophages. Inhibition of macrophage recruitment by AnSCs may be achieved indirectly via inhibiting CCL7 expression in fibroblasts; both let-7b and let-7a were highly enriched in AnSC-Exos and may play a critical role in the inhibition of CCL7 expression of fibroblasts. Collectively, the use of antler stem cells or their exosomes opens up a novel strategy for PF treatment in the clinical setting.

The effect of crevice size on the crevice corrosion of N80 carbon steel was investigated by electrochemical measurements and surface analysis in a CO2-saturated NaCl-HAc solution. The N80 carbon steel exhibits a high susceptibility to crevice corrosion in this environment, which can be initiated immediately without an induction period for specimens with crevice sizes of 100 μm, 300 μm, and 500 μm. Typically, crevice solutions become more acidic during crevice corrosion; however, in this study, the crevice solution became alkaline, resulting in galvanic corrosion between the inner and outer steel surfaces and leading to severe crevice corrosion. The pH levels of the crevice solution for specimens with 100 μm and 300 μm crevice sizes are similar, but both are notably higher than that of the specimen with a 500 μm crevice size. As a result, there is no significant difference in the crevice corrosion phenomenon between specimens with 100 μm and 300 μm crevice sizes, but it is more severe than in the specimen with a 500 μm crevice size.

The unusual daytime F-region Field-Aligned Irregularities (FAIs) were observed by the HCOPAR and the satellites at low latitudes on 13 June 2022. These irregularities survived from night-time to the following afternoon at 15:00 LT. During daytime, they appeared as fossil structures with low Doppler velocities and narrow spectral widths. These characteristics indicated that they drifted along the magnetic field lines without apparent zonal velocity to low latitudes. Combining the observations of the ICON satellite and the Hainan Digisonde, we derived the movement trails of these daytime irregularities. We attributed their generation to the rapid ascent of the F-layer due to the fluctuation of IMF Bz during the quiet geomagnetic conditions. Subsequently, the influence of the substorm on the low-latitude ionosphere was investigated and simulated. The substorm caused the intense Joule heating that enhanced the southward neutral winds, carrying the neutral compositional disturbances to low latitudes and resulting in a negative storm effect in Southeast Asia. The negative storm formed a low-density circumstance and slowed the dissipation of the daytime FAIs. These results may provide new insights into the generation of post-midnight irregularities and their relationship with daytime fossil structures.

Abstract The Industrial Internet of Things (IIoT) enables the improvement of the productivity and intelligent level of factory. The procedure of product quality inspection has generally adopted machine intelligence algorithms instead of manual operation to improve efficiency. In this paper, we propose a product quality inspection system scheme based on software-defined edge intelligent controller (SD-EIC). By adopting the software definition and resource virtualization technologies, the hardware platform of SD-EIC is designed to support the real-time control tasks and non-real-time edge computing tasks at the same time. To this end, we propose the scheme and architecture of product quality inspection system based on SD-EIC. Multiple virtual controllers and virtual edge computing nodes are constructed on a set of SD-EIC hardware platform to realize the integrated deployment of the real-time control for terminal devices and the AI model reasoning of product defect recognition algorithm based on machine vision respectively. In addition, the management and control scheme of product quality inspection system based on industrial information model is proposed. By constructing the semantic-based digital twin information model of terminal device, the flexible adjustment and parameter configuration of terminal device are realized to meet the demands of flexible production and manufacturing. The proposed product quality inspection system solution can effectively improve the utilization of hardware resources and the efficiency of product quality inspection, and reduce the overall deployment cost of the system. It can flexibly adapt to product diversity and different industrial scenarios.

Nicotine and nornicotine-typed compounds are well-known for its potential as insecticide. Some researches have shown that nicotine was highly toxic to Diaphorina citri Kuwayama, an invasive and fast spreading pest. Here we report the effects of nornicotine-typed insecticide against D. citri. Novel compounds A1-A8, B1–B28, C1–C18 and D1-D12 were synthesized by reported procedure. And bioassays indicated that some of these compounds exhibited good effects against D. citri. Compounds B2, B3, B8, B12, B13, B22, C5, C7, D5, and D9 exhibited the mortality up to 100% within 120 h in 50 mg/L. And further data shows that A2-5, A7, B1, B8, B20 and B22 showed rapid insecticidal activities against D. citri in 24 h with the low LC50 (LC50

This study employed network pharmacology, molecular docking technology, and modern pharmacological research methods to explore the pre-protective effect and underlying mechanism, Sanwei sandalwood decoction, against Adriamycin-induced Chronic Heart Failure, with a particular focus on the involvement of aquaporins. Additionally, the study highlighted aquaporins as a significant factor, affecting processes such as cell proliferation and response to reactive oxygen species. The results of in vivo experiments demonstrated that the administration of Sanwei sandalwood decoction in rats with chronic heart failure led to an enhancement in the ejection fraction and improved heart ejection function. Additionally, the decoction significantly reduced the serum levels of Creatine Kinase, Creatine Kinase-MB, and N-terminal pro-B-type natriuretic peptide. Furthermore, the relative expression of Aquarporin-1, 4, and 7mRNAs and proteins in the hearts of rats with chronic heart failure was down-regulated upon treatment. Overall, Sanwei sandalwood decoction can have an effective cardioprotective effect in preventing Adriamycin-induced Chronic Heart Failure in rats.

Extracellular vesicles (EVs) from antler reserve mesenchymal (RM) cells play an important role in the paracrine regulation during rapid growth of antler without forming a tumor; therefore, RM-EVs become novel materials for anti-tumor studies, such as osteosarcoma treatment. However, the problem of low production of RM-EVs in traditional 2D culture limits its mechanism research and application. In this study, we established an optimal 3D culture system for antler RM cells to produce EVs (3D-RM-EVs). Morphology and property of harvested 3D-RM-EVs were normal compared with EVs from conventional 2D culture, and the miRNA profile in them was basically the same through transcriptome sequencing analysis. Based on the same number of RM cells, the volume of the culture medium collected by 3D cultural system concentrated nearly 30 times, making it more convenient for subsequent purification. In addition, EVs were harvested 30 times in 3D cultural system, greatly increasing the total amount of EVs (harvested a total of 2–3 times in 2D culture). Although 3D-RM-EVs had a limited inhibitory effect on the proliferation of K7M2 cells, the inhibition effect of 3D-RM-EVs loaded drugs (Ifosfamide + Etoposide) were more significant than that of positive drug group alone ( P < 0.05). Furthermore, in vivo studies showed that 3D-RM-EVs loaded drugs (Ifosfamide + Etoposide) had the most significant tumor inhibition effect, with decreased tumor size, and could slow down body weight loss compared with Ifosfamide + Etoposide (IFO + ET) group. These results demonstrated that 3D-RM-EVs were efficiently prepared from antler RM cells and were effective as drug vehicles for the treatment of osteosarcoma.

Soil salinity is a major factor threatening the production of crops around the world. Smooth bromegrass (Bromus inermis L.) is a high-quality grass in northern and northwestern China. Currently, selecting and utilizing salt-tolerant genotypes is an important way to mitigate the detrimental effects of salinity on crop productivity. In our research, salt-tolerant and salt-sensitive varieties were selected from 57 accessions based on a comprehensive evaluation of 22 relevant indexes, and their salt-tolerance physiological and molecular mechanisms were further analyzed. Results showed significant differences in salt tolerance between 57 genotypes, with Q25 and Q46 considered to be the most salt-tolerant and salt-sensitive accessions, respectively, compared to other varieties. Under saline conditions, the salt-tolerant genotype Q25 not only maintained significantly higher photosynthetic performance, leaf relative water content (RWC), and proline content but also exhibited obviously lower relative conductivity and malondialdehyde (MDA) content than the salt-sensitive Q46 (p < 0.05). The transcriptome sequencing indicated 15,128 differentially expressed genes (DEGs) in Q46, of which 7,885 were upregulated and 7,243 downregulated, and 12,658 DEGs in Q25, of which 6,059 were upregulated and 6,599 downregulated. The Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that the salt response differences between Q25 and Q46 were attributed to the variable expression of genes associated with plant hormone signal transduction and MAPK signaling pathways. Furthermore, a large number of candidate genes, related to salt tolerance, were detected, which involved transcription factors (zinc finger proteins) and accumulation of compatible osmolytes (glutathione S-transferases and pyrroline-5-carboxylate reductases), etc. This study offers an important view of the physiological and molecular regulatory mechanisms of salt tolerance in two smooth bromegrass genotypes and lays the foundation for further identification of key genes linked to salt tolerance.

With the development of energy storage system, the voltage-controlled converters (VCCs) that can achieve voltage and frequency support have become hot spots in both theory and practice. Therefore, apart from the traditional multiple parallel current-controlled converters (CCCs), multiple parallel VCCs and multiple parallel hybrid-controlled converters (HCCs) consisting of both the CCCs and VCCs have emerged, which makes stability issues of multi-converter grid-connected systems more complex. To cope with stability concerns related to different kinds of multiple parallel converter systems, this paper analyzes the interactive process of circuit-coupling and frequency-coupling among grid-connected converters and develops equivalent sequence-admittance-based stability analysis models. Based on the proposed models, stability recognition of grid-connected CCCs, VCCs and HCCs are derived. Finally, the effectiveness of the built models and the correctness of the stability analysis results are verified by experiments.

To improve the breaking performances of current injection vacuum DC circuit breaker (DCCB), a double-break current injection DCCB proposed. The opening moments of the two breaks are not simultaneously, one of the breaks is arc breaking, which is used for cut off the fault current, and the other is non-arc breaking, which is used to enhance the transient recovery voltage (TRV) withstand capability. During the interruption process, let the arc-breaking contact first open, the contact starts to separate and produce arcs, then the pre-charged capacitor injects a reverse current to extinguish the arc, meanwhile, the current commutation of non-arc-breaking contact is realized by a coupling inductor. In addition, freewheeling diodes connected in parallel at the contacts to delay the occurrence of transient recovery voltage, thereby further increasing the voltage withstand capability of the CB. The principle and analysis of proposed DCCB scheme are discussed. Finally, the effectiveness of the proposed DCCB scheme is verified by simulation

ObjectiveTo investigate the effects of Sanwei sandalwood decoction on improving function of the intestinal flora in doxorubicin-induced heart failure in rats.Materials and methodsThirty Sprague–Dawley rats were screened and randomly assigned into a blank group, a model group, and a Sanwei sandalwood decoction group (treatment group). The rat model of heart failure was prepared and established in the latter two groups. After successful model establishment, the treatment group received Sanwei sandalwood decoction by continuous gavage at 2 g/kg, once daily for 4 weeks. The other groups were given an equivalent volume of saline. After the final dose, fecal samples were collected from each group and analyzed by macrogenomics and nontargeted metabolomics to characterize the intestinal flora and associated metabolites.ResultsThe composition of gut microbiota was significantly different between the three groups. There were 778,808 common genes between the blank and model groups, while 49,315 genes were lost and 521,008 were gained in the model group relative to the blank group. At the phylum level, all groups of rat fecal samples were dominated by Firmicutes, Bacteroidota, Actinobacteria, and Proteobacteria. At the genus level, the microbial community composition in all experimental groups of rat fecal samples was dominated by Lactobacillus, Bifidobacterium, Limosilactobacillus, Allobaculum, Prevotella, and Ligilactobacillus spp. Interestingly, cluster analysis was performed on the top 30 KEGG ontology (KO) terms displaying significant differences in relative abundance in the rat fecal microbiome among experimental groups. The relative frequency of posttranslational modification, coenzyme transport and metabolism, cell wall, membrane, and envelope biogenesis in the eggNOG and CAZy databases. In the nontargeted metabolomics, the group principal component analysis revealed that the groups were well distinguished from one another. The different metabolites were screened with VIP >1, and the KEGG different metabolite classification and enrichment analysis revealed that there includes 15 metabolites pathway, including loxoprofen, conifery-l-acetate, trichilin A, and others. The arachidonic acid pathway also accounted for a significant portion of the KEGG pathway classification analysis.ConclusionSanwei sandalwood decoction positively affects the intestinal microbial environment of rats with heart failure, improving the gut dysbiosis that is caused by the condition. This treatment intervention inhibits the growth of pathogenic bacteria and promotes the growth of beneficial species.

Sika deer are known to prefer oak leaves, which are rich in tannins and toxic to most mammals; however, the genetic mechanisms underlying their unique ability to adapt to living in the jungle are still unclear. In identifying the mechanism responsible for the tolerance of a highly toxic diet, we have made a major advancement by explaining the genome of sika deer. We generated the first high-quality, chromosome-level genome assembly of sika deer and measured the correlation between tannin intake and RNA expression in 15 tissues through 180 experiments. Comparative genome analyses showed that the UGT and CYP gene families are functionally involved in the adaptation of sika deer to high-tannin food, especially the expansion of the UGT family 2 subfamily B of UGT genes. The first chromosome-level assembly and genetic characterization of the tolerance to a highly toxic diet suggest that the sika deer genome may serve as an essential resource for understanding evolutionary events and tannin adaptation. Our study provides a paradigm of comparative expressive genomics that can be applied to the study of unique biological features in non-model animals.

State estimation plays a central role in ensuring the secure operation of the smart grid. However, deliberately designed false data injection attacks (FDIAs) can pass by conventional detections to manipulate the process of state estimation by injecting malicious data into measurements. Ultimately, FDIAs make the result of state estimation deviate from secure value and affect the security and stable operation of the power system. In this paper, we consider the different distribution characteristics between normal measurements and false measurements and build a Gaussian mixture model (GMM). Particularly, we focus on achieving joint detection and localization of FDIAs. To tackle these challenges, a model-based algorithm named Joint Maximum a Posteriori - Maximum Likelihood (JMAP-ML) is proposed to estimate the individual parameters of GMM and achieve joint detection and localization of FDIAs with high accuracy. Different testing scenarios in the IEEE-14-bus and IEEE-30-bus power systems are simulated to show the performance of the proposed algorithm on parameters estimation, FDIAs detection and localization. Numerical examples demonstrate the proposed algorithm achieves satisfactory results in detecting and localizing FDIAs compared to the other algorithms.

Power system state estimation is an essential component of the modern power system energy management system (EMS), and accurate state estimation is an indispensable basis for subsequent work. However, the attacker can inject biases into measurements to launch false data injection attacks (FDIAs) in smart grids, which ultimately cause state estimates to deviate from security values. This paper proposed the joint use of static state estimation and dynamic state estimation to detect the FDIA, i.e. the joint use of weighted least squares (WLS) and extended Kalman filter (EKF) with exponential weighting function (WEKF), which improves the robustness of state estimation. Since the WLS estimation considers only the measurements at the current moment, the recursive feature of the WEKF enables the estimation process to involve both historical state and current measurements. Therefore, consistency tests and residual tests were performed using the estimations of WLS and WEKF to effectively detect FDIA. In addition, a cluster partitioning approach with approximate equal redundancy of subsystems is proposed to locate the FDIA. The detection of FDIA triggers the partitioning of the network system, and then the chi-square test is used separately in each sub-network to determine the location of FDIA. Finally, the experimental results in the IEEE-14 bus system and the IEEE-30 bus system demonstrate that the approach can effectively detect and locate FDIAs.

Abstract Deer antlers constitute a unique mammalian model for the study of both organ formation in postnatal life and annual full regeneration. Previous studies revealed that these events are achieved through the proliferation and differentiation of antlerogenic periosteum (AP) cells and pedicle periosteum (PP) cells, respectively. As the cells resident in the AP and the PP possess stem cell attributes, both antler generation and regeneration are stem cell-based processes. However, the cell composition of each tissue type and molecular events underlying antler development remain poorly characterized. Here, we took the approach of single-cell RNA sequencing (scRNA-Seq) and identified eight cell types (mainly THY1 + cells, progenitor cells, and osteochondroblasts) and three core subclusters of the THY1 + cells (SC2, SC3, and SC4). Endothelial and mural cells each are heterogeneous at transcriptional level. It was the proliferation of progenitor, mural, and endothelial cells in the activated antler-lineage-specific tissues that drove the rapid formation of the antler. We detected the differences in the initial differentiation process between antler generation and regeneration using pseudotime trajectory analysis. These may be due to the difference in the degree of stemness of the AP-THY1+ and PP-THY1+ cells. We further found that androgen-RXFP2 axis may be involved in triggering initial antler full regeneration. Fully deciphering the cell composition for these antler tissue types will open up new avenues for elucidating the mechanism underlying antler full renewal in specific and regenerative medicine in general.

Abstract Microgrid clusters (MGC) can improve the consumption of renewable energy and the system reliability. The control of microgrid cluster with large‐scale microgrids is the focus of microgrid cluster research. In order to better realize the coordination control and energy scheduling among microgrids, this paper proposes a distributed optimal strategy for complex MGC based on model predictive control (MPC) and block‐wised alternating direction multiplier method (BADMM). Firstly, an optimization model is established based on a honeycomb active distribution network (HADN); then the network is decomposed into several regions according to BADMM. The global optimization goal of the cluster is achieved by iterating the optimization results of each region in a time domain. Finally, the case study results verify the effectiveness and convergence of the proposed distributed optimization strategy, and provide a reference for energy management of MGC.

The inverter becomes an essential part in the distributed energy units, where an inductor–capacitor–inductor (LCL) filter is an up-to-date adoption for grid interfacing. However, the challenging issue of resonance related to the LCL-filter worsens the dynamic control characteristics and produces stability threat for the voltage source inverter system. The proper design of inverter control plays a substantial part in ensuring a steady state operation and a high quality of grid injected current according to grid connection codes. This paper offers a different design method of inverter control which alters the inner damping loop structure to enhance the damping and stability features of the inverter system. In the proposed solution, a modified compensator is employed through the LCL filter network and filter capacitor current feedback loop, the resultant augmented plant’s output is then sent back at the reference point of a grid-connected inverter system to damp the unwanted resonance spike. This particular arrangement to form a damping loop is termed as parallel feedforward compensation. The damping loop is implemented by calculating the filter capacitor current, and a first order high-pass filter is employed as a damper in the suggested arrangement. Moreover, for comparative studies and analysis, the conventional filter capacitor current feedback active damping method is selected. In addition, the stability margins and control performance of the open current loop are examined under different filter parameters values. The substantial results of the suggested structure are quicker dynamic response, comparatively improved resonance damping, better tracking performance and higher delay compensation capability. A laboratory prototype is established to confirm the effectiveness of the suggested scheme on the bases of control performance and stability margins.

With the constant development of power, information and other technologies, the advantages of unmanned ships are emerging in anti-mine, anti-submarine, electronic warfare, maritime security, maritime interception, and other military fields. This paper describes the development of unmanned ships and power technology and clarifies that the integrated power system has become a major trend of medium and large-sized unmanned ships. It also introduces the application of integrated power system in manned and unmanned platforms, and proposes that issues like size, weight, and control of vibration and noise are of essential for the integrated power system for unmanned platforms. In the end, this paper summarizes the trend of integrated power technology for unmanned platforms and identifies the key scientific problems of integrated power technology on unmanned platform, namely the intelligent operation of integrated power system, high-performance motor materials, information perception of complex motor system, power electronic device and system, high-performance power conversion and efficient energy storage.

As a promising material for petroleum industrial applications, titanium (Ti) and its alloys receive wide attention due to their outstanding physicochemical properties. However, the harsh industrial environment requires an antifouling surface with a desired corrosion resistance for Ti and its alloys. In order to achieve the desired antifouling properties, micro-arc oxidation (MAO) was used to prepare a Cu-doped TiO2 coating. The microstructure of the Cu-doped TiO2 coating was investigated by TF-XRD, SEM, and other characterization techniques, and its antifouling and anticorrosion properties were also tested. The results show the effects of the incorporation of Cu (~1.73 wt.%) into TiO2 to form a Cu-doped TiO2, namely, a Ti–Cu coating. The porosity (~4.8%) and average pore size (~0.42 μm) of the Ti–Cu coating are smaller than the porosity (~5.6%) and average pore size (~0.66 μm) of Ti–blank coating. In addition, there is a significant reduction in the amount of SRB adhesion on the Ti–Cu coating compared to the Ti–blank coating under the same conditions, while there is little difference in corrosion resistance between the two coatings. There, the addition of copper helps to improve the fouling resistance of TiO2 coatings without compromising their corrosion resistance. Our work provides a practical method to improve the antifouling function of metallic Ti substrates, which could promote the application of Ti in the petroleum industry.

Catalysts play a pivotal role in modern industries, such as energy, pharmaceuticals, and petrochemicals, serving as cornerstone of high-tech production. Noble metals, such as gold, silver, and platinum group elements, possess the superb catalytic characteristics of high-temperature oxidation resistance, corrosion resistance, stable electrochemical performance, high catalytic activity, and so on. These characteristics offer excellent prospects for applications in catalysis. In this review, we summarize innovative approaches to regulating the size and morphology of nano-noble metal catalysts with different dimensions. We also showcase typical prominent examples of their applications in exhaust gas purification, battery manufacturing, water splitting, and selective hydrogenation. Finally, perspectives are discussed in terms of future research opportunities in the realm of noble metal nanocatalysts.

Resonance related to the LCL-filter grid-connected inverter (GCI) is one of the most challenging issues in power electronics. Active damping is a widely used methodology to damp the resonance problem due to its effective control structure. In capacitor current feedback active damping methodologies, a compensator is primarily required in the feedback loop where the damping efficiency depends on the imitated features of the compensator. Such capacitor current feedback damping techniques encounter restrictions in their layout at the critical resonance frequency and may need extra amendment in the delay to assure stability. This paper proposes a different design method called parallel feedforward compensation method, which designs an almost strictly real positive plant and achieved damping with enhanced stability features. In the proposed alternative, a first-order high pass filter is used as a compensator across the LCL filter plant and filter capacitor current feedback loop. The resultant output of this augmented plant is then transmitted back at the reference point of a GCI system to attenuate the undesirable resonance peak. The key benefits of the proposed method are efficient damping without any limitation of critical resonance frequency region, better control characteristics, improved damping area, and better robustness under variations in filter parameters. The simulation and experimental outcomes based on transient response and steady-state analysis are demonstrated to validate the efficacy of the suggested method.

Lanthanide-doped heterostructured nanocomposites were developed by using cation exchange method and successfully applied toward advanced optical anti-counterfeiting and information storage

An accurate power state is the basis of the normal functioning of the smart grid. However, false data injection attacks (FDIAs) take advantage of the vulnerability in the bad data detection mechanism of the power system to manipulate the process of state estimation. By attacking the measurements, then affecting the estimated state, FDIAs have become a serious hidden danger that affects the security and stable operation of the power system. To address the bad data detection vulnerability, in this paper, a false data attack detection method based on weighted least squares (WLS) and an adaptive interpolation extended Kalman filter (AIEKF) is proposed. On the basis of applying WLS and AIEKF, the Euclidean distance is used to calculate the deviation values of the two-state estimations to determine whether the current moment is subjected to a false data injection attack in the power system. Extensive experiments were conducted to simulate an IEEE-14-bus power system, showing that the adaptive interpolation extended Kalman filter can compensate for the deficiency in the bad data detection mechanism and successfully detect FDIAs.

Outliers can be generated in the power system due to aging system equipment, faulty sensors, incorrect line connections, etc. The existence of these outliers will pose a threat to the safe operation of the power system, reduce the quality of the data, affect the completeness and accuracy of the data, and thus affect the monitoring analysis and control of the power system. Therefore, timely identification and treatment of outliers are essential to ensure stable and reliable operation of the power system. In this paper, we consider the problem of detecting and localizing outliers in power systems. The paper proposes a Minorization–Maximization (MM) algorithm for outlier detection and localization and an estimation of unknown parameters of the Gaussian mixture model (GMM). To verify the performance of the method, we conduct simulation experiments by simulating different test scenarios in the IEEE 14-bus system. Numerical examples show that in the presence of outliers, the MM algorithm can detect outliers better than the traditional algorithm and can accurately locate outliers with a probability of more than 95%. Therefore, the algorithm provides an effective method for the handling of outliers in the power system, which helps to improve the monitoring analyzing and controlling ability of the power system and to ensure the stable and reliable operation of the power system.

Abstract With the increasing penetration of large‐scale distributed renewable energies, the electricity distribution network is growing more complex with challenges brought by the intermittency and uncertainty of renewable energies. Microgrid (MG), one of feasible solutions to integrating renewable energies, has shortages because of limited capacity. Therefore, MG cluster (MGC) was proposed as an improved solution. To efficiently and friendly integrate renewable energies, a novel honeycomb‐like MG cluster (H‐MGC) is proposed in this paper. Considering the uncertainty of renewable energies, a robust optimisation method of the siting and sizing of energy storage system (ESS) constrained by emergency reserve is proposed. Combining the column‐and‐constraint generation algorithm and big‐M method, the proposed optimisation model is decomposed into mixed integer second‐order cone programming master problem and sub‐problems, which are alternately solved. Based on the optimal results of study case, the siting and sizing results of ESS are analysed, as well as the operating characteristics of H‐MGC. Compared to existing MGC system, the proposed H‐MGC has a more flexible operation mode. The related costs of ESS are reduced, and the operational life is relatively extended, under the condition that the emergency reserve of system is satisfied.

Sanwei sandalwood decoction (SWTX) is a classical Chinese medicine formula and clinically effective treatment for coronary heart disease, including myocardial ischemia/reperfusion (I/R) injury. Because the treatment mechanism of SWTX in I/R injury remains obscure, we intended to analyze the potential cardioprotective effects of SWTX in rats with myocardial I/R injury. Our research revealed that SWTX prolonged ventricular conduction time in a dose-dependent manner. While SWTX significantly delayed left ventricular signal conduction velocity, it had no effect on left atrial conduction velocity. Under sinus conditions, low SWTX concentrations reduced left ventricular conduction dispersion, while high concentrations increased conduction dispersion. SWTX also prolonged the QRS interval, APD30/50/90, and ERP. In whole-cell patch clamp experiments on myocytes, Ito and Ikr were inhibited by SWTX. While SWTX had no effect on INa, the activation curve for Nav1.5 was left-shifted. Finally, SWTX reduced the probability of ventricular fibrillation and suppressed early and late depolarization in an acute I/R injury rat model. These findings shed light on the mechanism by which SWTX alleviates myocardial I/R injury.

Objective. To explore the clinicopathological features and risk factors of patients with multiple primary breast cancers and thyroid disease. Method. An analytic approach of the reviewing method was adopted to analyze the clinical data of 80 breast cancer patients who were admitted to our hospital from January 2020 to January 2022. They were divided into an observation group (breast cancer with thyroid lesions) and a control group (simple breast cancer) according to whether the clinical data were accompanied with thyroid lesions to compare the clinical characteristics, pathological types, staging characteristics, and molecular biological characteristics of the two groups and to research the risk factors of the two groups. Result. (1) In the comparison of clinical data, the number of people aged ≥60 in the observation group was higher than that in the control group, and there was significant difference between the groups in the menopausal status data (P0.05). (2) In the comparison of pathological type and staging data, there was no statistical difference in the comparison of data on the pathological type, histological grade, T staging, N staging, and TNM staging between the observation group and the control group (P>0.05). (3) In the comparison of data on molecular biology characteristics, there was a statistical difference in the nuclear proliferation antigen data between the observation group and the control group (P0.05). (4) Logistic regression analysis showed that age, menopausal status, and nuclear proliferation antigen index were the high-risk inflammatory factors for combined thyroid lesions (P

Abstract Aiming at the fast protection requirements of electrical ships LVDC distribution system, this paper studies a topology of unidirectional vacuum hybrid circuit breaker. The hybrid circuit breaker is an improved current injection LVDC breaker based on precharged capacitor, which improves the dielectric recovery capability of vacuum interrupter after artificial current zero by using a freewheel diode. A synthetic test platform is built to study the dielectric strength recovery characteristics of a 45 mm diameter CuCr50 butt contact vacuum interrupter (driven by Thomson coil actuator, average opening speed of about 3 m/s)under high current(about 20 kA) and small gap(about 1 mm). The experimental results indicate that the dielectric strength of the contact can recover at a very fast speed within the arc time of 100 µs; when the arc time is increased to 320 µs, the dielectric strength of the contact cannot recover for a long time. Therefore, the design principle of the circuit breaker is obtained: within the arc time of 100 µs, by increasing the arc time can increase the contact distance, so the transient interruption voltage tolerance margin of the circuit breaker can be improved. Based on the results of the test, this paper also proposes a calculation method of forced commutation circuit parameters, which is verified by the simulation. The research results show that the DC circuit breaker can realise the rapid breaking of 20 kA fault current within 2 ms, and has a good application prospect in the LVDC distribution system.

Astragalus membranaceus, as an important medicinal plant, are an excellent source of flavonoids. Flavonoid compounds in A. membranaceus have been widely used in medicine and supplement, but known of the molecular mechanism of flavonoid biosynthesis is still very few. Here, we analyzed the association between flavonoid content and gene expression pattern during six different fruit developmental stages. Sixteen gene expression trends were significantly identified, involving 8,218 genes. The gene expression trend in profile 0 was positively correlated with flavonoid content, while the gene expression trend in profile 79 was negatively correlated with flavonoid content at six developmental stages. The expression level of genes involved in the general phenylpropane pathway was higher than that of genes involved in the flavonoid biosynthesis pathway. A total of 37 genes involved in flavonoid synthesis were identified in A. membranaceus. The expression pattern of flavonoid-related genes was highly correlated with flavonoid content. Our study deepened the understanding of the flavonoid synthesis mechanism and provided useful resources for future studies on the high flavonoid molecular breeding of A. membranaceus.

The Phasor Measurement Unit (PMU) with a GPS signal receiver is a synchronized sensor widely used for power system state estimation. While the GPS receiver ensures time accuracy, it is vulnerable to network attacks. GPS spoofing attacks can alter the phase angle of PMU measurement signals and manipulate system states. This paper derives a power system state model based on PMUs under GPS spoofing attacks, according to the characteristics of changes in bus voltages and branch currents after GSA. Based on the characteristics of this model, a detection and correction algorithm for attacked data is proposed to detect GSA and correct attacked measurements. The corrected measurements can be used for power system state estimation. Simulation results on the IEEE 14-bus system show that the proposed algorithm improves the accuracy of state estimation under one or multiple GSAs, especially when multiple GSAs are present, compared to classical Weighted Least Squares Estimation (WLSE) and Alternating Minimization (AM) algorithms. Further research indicates that this algorithm is also applicable to large-scale networks.

Numerous contemporary studies have examined safe sexual behavior among college students. In China, families are reluctant to discuss sexual behavior, thus understanding and exploring the sexual knowledge of college students and the promotion of safe sexual behavior is essential. On the basis of the theory of planned behavior (TPB), a cognitive behavioral theory that is widely used to predict human social behavior, we conducted an in-depth investigation of the factors influencing the sexual behavioral intentions of Chinese college students. We referenced the relevant literature to develop a TPB-based model for analyzing differences in sexual knowledge. Our statistical analysis revealed the following: (1) subjective norms and behavior control are key variables that influence the safe sexual behavior of college students; (2) attitudes and safe-sex behavioral intentions are influential in groups with extensive sexual knowledge; (3) behavioral control and subjective norms influence the differences in the comparative sexual knowledge of students. On the basis of the present results, we propose research recommendations and directions for the development of sex education in China.

The present work aimed to study the effect of slurry conditioning on flocculant-aided filtration of coal tailings by the analysis of filtration kinetics and filter cake structure. Laboratory filtration tests of the coal tailings showed that both the shear rate and agitation time have significant effects on filtration rate and cake moisture. Moderate agitation at the shear rate of 92 s−1 was favorable for fast filtration, but high cake moisture was encountered. The low-field 1H nuclear magnetic resonance (NMR) measurements of the filter cake showed that the slurry conditioning has a significant effect on the residual water in large pores and a negligible effect on the residual water in small pores. The X-ray micro-tomography (XRM) measurements indicated that the filter cake formed at the shear rate of 92 s−1 has more macro-pores and higher porosity than that formed at the shear rate of 53 s−1, hence more residual water was entrapped in filter cake. The slurry conditioning in the presence of flocculant will change the structure of filter cake and affect the filtration performance. There was a paradox between fast filtration rate and low filter cake moisture. The findings enable better understanding of the effect of slurry conditioning on flocculant-aided filtration of coal tailings.

The behavior of potassium chloride (KCl) as a main mud shale inhibitor remains poorly defined in the interlayer of montmorillonite (Mt). In this paper, a new analysis method of transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDS) was established. The distribution of K+ in the interlayer of Mt and the processes surrounding d-spacing shifts in Mt were investigated through X-ray diffraction and TEM-EDS. The experimental results revealed shoulder peaks in the diffraction patterns at KCl concentrations between 11% and 19%. The distribution of K+ varied in the inner and outer layers of Mt with different KCl concentrations. It could be concluded that the distribution of K+ and the changes in d-spacing of Na are determined by two factors: negative charge sites and concentration difference. When the KCl concentration was below 8%, both factors cause the outer layer of Mt to adsorb more K+ than the inner layer, with all layers exhibiting d-spacings within the 1.50 nm state. At an 8% KCl concentration, all negative charge sites were occupied by K+. As the KCl concentration rose above 8%, the outer layer of Mt adsorbed more K+ than the inner layer due to the concentration difference. With a further increase in the KCl concentration, the d-spacing shifted linearly to 1.30 nm from the outer to the inner layer of Mt. All layers of Mt exhibited a d-spacing of 1.30 nm at KCl concentrations of up to 23%. These results demonstrate the benefits and capabilities of the proposed method in investigating the intercalating mechanisms of Mt.

In this paper, a modular multiple DC (MMDC) transformer based DC transmission system, which is used for permanent magnetic synchronous generator (PMSG) based offshore wind farm grid connection, is proposed. The MMDC transformer is composed of input-parallel output-series (IPOS) DC/DC submodule groups, each of which consists of several input-series output-series (ISOS) LLC resonant converters (i.e., submodules). In the offshore wind farm, the electrical power generated by PMSG is converted to DC power by diode rectifier. Compared with the existing offshore wind farm grid-connection schemes, the proposed system has advantages of fewer conversion stages, higher efficiency and lower cost. The mathematical relationship of the system is studied, and then one kind of control strategy is proposed. Furthermore, a detailed DC transmission system simulation model containing a 160 submodules (LLC resonant converters) based MMDC transformer is built in PSCAD/EMTDC. Finally, a down-scaled experimental prototype of the DC system, which includes 9 submodules, is presented. Both simulation and experimental results validate the feasibility of the proposed DC system and effectiveness of the control strategy.