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The binding of peroxisome proliferator‐activated receptor γ (PPARγ) to the orphan nuclear receptor Nur77 facilitates the ubiquitination and degradation of Nur77, and leads to aberrant fatty acid uptake for breast cancer progression. Because of its crucial role in clinical prognosis, the interaction between Nur77 and PPARγ is an attractive target for anti‐breast‐cancer therapy. However, developing an inhibitor of the Nur77‐PPARγ interaction poses a technical challenge due to the absence of the crystal structure of PPARγ and its corresponding interactive model with Nur77. Here, ST‐CY14, a stapled peptide, is identified as a potent modulator of Nur77 with a KD value of 3.247 × 10−8 M by in silico analysis, rational design, and structural modification. ST‐CY14 effectively increases Nur77 protein levels by blocking the Nur77‐PPARγ interaction, thereby inhibiting lipid metabolism in breast tumor cells. Notably, ST‐CY14 significantly suppresses breast cancer growth and bone metastasis in mice. The findings demonstrate the feasibility of exploiting directly Nur77‐PPARγ interaction in breast cancer, and generate what to the best knowledge is the first direct inhibitor of the Nur77‐PPARγ interaction available for impeding fatty acid uptake and therapeutic development. [ABSTRACT FROM AUTHOR]

Targeting the programmed cell death 1/programmed cell death ligand 1 (PD‐1/PD‐L1) pathway has been identified as a successful approach for tumor immunotherapy. Here, we identified that the small molecule 5,7,4′‐trimethoxyflavone (TF) from Kaempferia parviflora Wall reduces PD‐L1 expression in colorectal cancer cells and enhances the killing of tumor cells by T cells. Mechanistically, TF targets and stabilizes the ubiquitin ligase HMG‐CoA reductase degradation protein 1 (HRD1), thereby increasing the ubiquitination of PD‐L1 and promoting its degradation through the proteasome pathway. In mouse MC38 xenograft tumors, TF can activate tumor‐infiltrating T‐cell immunity and reduce the immunosuppressive infiltration of myeloid‐derived suppressor cells and regulatory T cells, thus exerting antitumor effects. Moreover, TF synergistically exerts antitumor immunity with CTLA‐4 antibody. This study provides new insights into the antitumor mechanism of TF and suggests that it may be a promising small molecule immune checkpoint modulator for cancer therapy. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) presents a formidable global health challenge, and conventional therapies face efficacy limitations. Ubiquitin‐specific protease 7 (USP7) plays pivotal roles in GC development, immune response, and chemo‐resistance, making it a promising target. Various USP7 inhibitors have shown selectivity and efficacy in preclinical studies. However, the mechanistic role of USP7 has not been fully elucidated, and currently, no USP7 inhibitors have been approved for clinical use. In this study, DHPO is identified as a potent USP7 inhibitor for GC treatment through in silico screening. DHPO demonstrates significant anti‐tumor activity in vitro, inhibiting cell viability and clonogenic ability, and preventing tumor migration and invasion. In vivo studies using orthotopic gastric tumor mouse models validate DHPO's efficacy in suppressing tumor growth and metastasis without significant toxicity. Mechanistically, DHPO inhibition triggers ferroptosis, evidenced by mitochondrial alterations, lipid Reactive Oxygen Species (ROS), Malondialdehyde (MDA) accumulation, and iron overload. Further investigations unveil USP7's regulation of Stearoyl‐CoA Desaturase (SCD) through deubiquitination, linking USP7 inhibition to SCD degradation and ferroptosis induction. Overall, this study identifies USP7 as a key player in ferroptosis of GC, elucidates DHPO's inhibitory mechanisms, and highlights its potential for GC treatment by inducing ferroptosis through SCD regulation. [ABSTRACT FROM AUTHOR]

Background: Mucinous colorectal adenocarcinoma (MCA) is a distinct subtype of colorectal cancer (CRC) with the most aggressive pattern, but effective treatment of MCA remains a challenge due to its vague pathological characteristics. An in‐depth understanding of transcriptional dynamics at the cellular level is critical for developing specialised MCA treatment strategies. Methods: We integrated single‐cell RNA sequencing and spatial transcriptomics data to systematically profile the MCA tumor microenvironment (TME), particularly the interactome of stromal and immune cells. In addition, a three‐dimensional bioprinting technique, canonical ex vivo co‐culture system, and immunofluorescence staining were further applied to validate the cellular communication networks within the TME. Results: This study identified the crucial intercellular interactions that engaged in MCA pathogenesis. We found the increased infiltration of FGF7+/THBS1+ myofibroblasts in MCA tissues with decreased expression of genes associated with leukocyte‐mediated immunity and T cell activation, suggesting a crucial role of these cells in regulating the immunosuppressive TME. In addition, MS4A4A+ macrophages that exhibit M2‐phenotype were enriched in the tumoral niche and high expression of MS4A4A+ was associated with poor prognosis in the cohort data. The ligand‐receptor‐based intercellular communication analysis revealed the tight interaction of MUC1+ malignant cells and ZEB1+ endothelial cells, providing mechanistic information for MCA angiogenesis and molecular targets for subsequent translational applications. Conclusions: Our study provides novel insights into communications among tumour cells with stromal and immune cells that are significantly enriched in the TME during MCA progression, presenting potential prognostic biomarkers and therapeutic strategies for MCA. Key points: Tumour microenvironment profiling of MCA is developed.MUC1+ tumour cells interplay with FGF7+/THBS1+ myofibroblasts to promote MCA development.MS4A4A+ macrophages exhibit M2 phenotype in MCA.ZEB1+ endotheliocytes engage in EndMT process in MCA. [ABSTRACT FROM AUTHOR]

Highly diverse exoenzymes mediate the energy flow from substrates to the multitrophic microbiota within the soil decomposer micro‐food web. Here, we used a "soil enzyme profile analysis" approach to establish a series of enzyme profile indices; those indices were hypothesized to reflect micro‐food web features. We systematically evaluated the shifts in enzyme profile indices in relation to the micro‐food web features in the restoration of an abandoned cropland to a natural area. We found that enzymatic C:N stoichiometry and decomposability index were significantly associated with substrate availability. Furthermore, the higher Shannon diversity index in the exoenzyme profile, especially for the C‐degrading hydrolase, corresponded to a greater microbiota community diversity. The increased complexity and stability of the exoenzyme network reflected similar changes with the micro‐food web networks. In addition, the gross activity of the enzyme profile as a parameter for soil multifunctionality, effectively predicted the substrate content, microbiota community size, diversity, and network complexity. Ultimately, the proposed enzymic channel index was closely associated with the traditional decomposition channel indices derived from microorganisms and nematodes. Our results showed that soil enzyme profile analysis reflected very well the decomposer food web features. Our study has important implications for projecting future climate change or anthropogenic disturbance impacts on soil decomposer micro‐food web features by using soil enzyme profile analysis. Highlights: Soil enzyme profile analysis for indicating decomposer micro‐food web features was first proposed.Diversity indication utilities for contrasting enzyme profiles were different.Protozoa channel index and enzymatic channel index were proposed. [ABSTRACT FROM AUTHOR]

Ionizing radiation (IR)‐induced intestinal injury is usually accompanied by high lethality. Intestinal stem cells (ISCs) are critical and responsible for the regeneration of the damaged intestine. Astragalus polysaccharide (APS), one of the main active ingredients of Astragalus membranaceus (AM), has a variety of biological functions. This study was aimed to investigate the potential effects of APS on IR‐induced intestine injury via promoting the regeneration of ISCs. We have established models of IR‐induced intestinal injury and our results showed that APS played great radioprotective effects on the intestine. APS improved the survival rate of irradiated mice, reversed the radiation damage of intestinal tissue, increased the survival rate of intestinal crypts, the number of ISCs and the expression of intestinal tight junction‐related proteins after IR. Moreover, APS promoted the cell viability while inhibited the apoptosis of MODE‐K. Through organoid experiments, we found that APS promoted the regeneration of ISCs. Remarkably, the results of network pharmacology, RNA sequencing and RT‐PCR assays showed that APS significantly upregulated the HIF‐1 signalling pathway, and HIF‐1 inhibitor destroyed the radioprotection of APS. Our findings suggested that APS promotes the regeneration of ISCs through HIF‐1 signalling pathway, and it may be an effective radioprotective agent for IR‐induced intestinal injury. [ABSTRACT FROM AUTHOR]

Sepsis is defined as "a life‐threatening organ dysfunction caused by dysregulated host systemic inflammatory and immune response to infection." At present, sepsis continues to pose a grave healthcare concern worldwide. Despite the use of supportive measures in treating traditional sepsis, such as intravenous fluids, vasoactive substances, and oxygen plus antibiotics to eradicate harmful pathogens, there is an ongoing increase in both the morbidity and mortality associated with sepsis during clinical interventions. Therefore, it is urgent to design specific pharmacologic agents for the treatment of sepsis and convert them into a novel targeted treatment strategy. Herein, we provide an overview of the molecular mechanisms that may be involved in sepsis, such as the inflammatory response, immune dysfunction, complement deactivation, mitochondrial damage, and endoplasmic reticulum stress. Additionally, we highlight important targets involved in sepsis‐related regulatory mechanisms, including GSDMD, HMGB1, STING, and SQSTM1, among others. We summarize the latest advancements in potential therapeutic drugs that specifically target these signaling pathways and paramount targets, covering both preclinical studies and clinical trials. In addition, this review provides a detailed description of the crosstalk and function between signaling pathways and vital targets, which provides more opportunities for the clinical development of new treatments for sepsis. [ABSTRACT FROM AUTHOR]

Purpose: To construct and evaluate the performance of a machine learning‐based low dose computed tomography (LDCT)‐derived parametric response mapping (PRM) model for predicting pulmonary function test (PFT) results. Materials and methods: A total of 615 subjects from a community‐based screening population (40–74 years old) with PFT parameters, including the ratio of the first second forced expiratory volume to forced vital capacity (FEV1/FVC), the percentage of forced expiratory volume in the one second predicted (FEV1%), and registered inspiration‐to‐expiration chest CT scanning were enrolled retrospectively. Subjects were classified into a normal, high risk, and COPD group based on PFT. Data of 72 PRM‐derived quantitative parameters were collected, including volume and volume percentage of emphysema, functional‐small airways disease, and normal lung tissue. A machine‐learning with random forest regression model and a multilayer perceptron (MLP) model were constructed and tested on PFT prediction, which was followed by evaluation of classification performance based on the PFT predictions. Results: The machine‐learning model based on PRM parameters showed better performance for predicting PFT than MLP, with a coefficient of determination (R2) of 0.749 and 0.792 for FEV1/FVC and FEV1%, respectively. The Mean Squared Errors (MSE) for FEV1/FVC and FEV1% are 0.0030 and 0.0097 for the random forest model, respectively. The Root Mean Squared Errors (RMSE) for FEV1/FVC and FEV1% are 0.055 and 0.098, respectively. The sensitivity, specificity, and accuracy for differentiating between the normal group and high‐risk group were 34/40 (85%), 65/72 (90%), and 99/112 (88%), respectively. For differentiating between the non‐COPD group and COPD group, the sensitivity, specificity, and accuracy were 8/9 (89%), 112/112 (100%), 120/121 (99%), respectively. Conclusions: The machine learning‐based random forest model predicts PFT results in a community screening population based on PRM, and it identifies high risk COPD from normal populations with high sensitivity and reliably predicts of high‐risk COPD. [ABSTRACT FROM AUTHOR]

As the Internet of things (IOT) industry continues to grow with an ever‐increasing number of connected devices, the need for processing large amounts of data in a fast and energy‐efficient way becomes an even more pressing issue. Alternative computation devices such as resistive random access memories (RRAM), or memristors, started taking centre stage as prime candidates to tackle this issue due to their in‐memory computation capabilities. Amorphous oxide semiconductors (AOSs), more specifically eco‐friendly zinc‐tin oxide (ZTO), show great promise as a memristive active material for flexible and sustainable applications due to its low required fabrication temperature, amorphous structure, low‐cost, and critical‐raw‐material‐free composition. In this perspective article, the research progress on ZTO‐based memristors is reviewed in terms of device structure and material compositions. The effects on the electrical performance of the devices are studied. Additionally, neuromorphic and optoelectronic capabilities are analyzed with the objective of finding the best approaches toward implementing these devices in novel computing paradigms. [ABSTRACT FROM AUTHOR]

Background: Despite all modern advances in medicine, an effective drug for treating sepsis has yet to be found. The discovery of CMPK2 spurred hopes for the treatment of sepsis. However, CMPK2‐untapped target inhibitors are still an enormous obstacle that has hindered the CMPK2‐centric treatment of sepsis. Methods: Here, we found that the CMPK2 gene is highly expressed in the whole blood of sepsis patients by RNA‐Seq. First, recombinant CMPK2 was purified by a eukaryotic expression purification system, and the activity of recombinant CMPK2 was detected by the ADP‐GLO assay. Second, we developed an affinity MS strategy combined with quantitative lysine reactivity profiling to discover CMPK2 ligands from the active ingredients of Chinese herbs. In addition, the dissociation constant Kd of the ligand and the target protein CMPK2 was further detected by microscale thermophoresis technology. Third, we used this strategy to identify a naturally sourced small molecule, dracorhodin (DP). Using mass spectrometry‐based quantitative lysine reactivity profiling combined with a series of mutant tests, the results show that K265 acts as a bright hotspot of DP inhibition of CMPK2. Fourth, immune‐histochemical staining, ELISAs, RT‐qPCR, flow cytometry and immunoblotting were used to illustrate the potential function and related mechanism of DP in regulating sepsis injury. Results: Our results suggest that DP exerts powerful anti‐inflammatory effects by regulating the NLRP3 inflammasome via the lipopolysaccharide (LPS)‐induced CMPK2 pathway. Strikingly, DP significantly attenuated LPS‐induced sepsis in a mouse model, but its effect was weakened in mice with myeloid‐specific Cmpk2 ablation. Conclusion: We provide a new framework that provides more valuable information for new therapeutic approaches to sepsis, including the establishment of screening strategies and the development of target drugs to provide a theoretical basis for ultimately improving clinical outcomes for sepsis patients. Collectively, these findings reveal that DP is a promising CMPK2 inhibitor for the treatment of sepsis. [ABSTRACT FROM AUTHOR]

Background: Adjuvant therapy for stage IB non‐small cell lung cancer remains debatable. In this real‐world study, we evaluate the efficacy and safety of adjuvant epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‐TKIs) for resected stage IB lung adenocarcinoma. Methods: This real‐world study recruited 249 patients diagnosed with stage IB disease after surgical resection between January 2013 and September 2021. Sixty‐six (26.5%) patients received adjuvant targeted therapy (TKIs group), and 183 (73.5%) were enrolled in the clinical observation (CO) group. Propensity scores were matched to minimize the observed confounder effects between the two groups, and 59 patient pairs were matched. The primary endpoint was disease‐free survival (DFS). Results: In the TKI group, 38 (64.4%) patients chose to receive icotinib, 27.1% (16/59) received gefitinib, and 5 patients (8.5%) chose osimertinib. The median follow‐up time was 30.8 months (range: 7–107 months). Two (3.4%) patients in the TKI group and 10 (16.9%) in the CO group experienced disease relapse. The 3‐year DFS rates were 98.3% in the TKI group and 83.0% in the CO group (HR: 0.10; 95% CI: 0.01–0.78; p = 0.008). DFS differences were found in the entire cohort (p = 0.005) and the matched cohort (p = 0.024) between the two groups. Multivariate analysis showed that adjuvant EGFR‐TKIs was an independent factor for DFS (HR: 0.211; 95% CI: 0.045–0.979; p = 0.047), along with poor cell differentiation (HR: 5.256; 95% CI: 1.648–16.769; p = 0.005), and spread through air spaces (HR: 5.612; 95% CI: 1.137–27.700; p = 0.034). None of the patients discontinued EGFR‐TKIs owing to the low occurrence rate of treatment‐related serious adverse events. Conclusion: Adjuvant EGFR‐TKIs could significantly improve DFS among patients with stage IB lung adenocarcinoma compared with CO, with a safe and tolerable profile. [ABSTRACT FROM AUTHOR]

Previously, we have found that (NbTaZrW)C exhibits a good combination of nanohardness and toughness. In this report, we explore the possibility to further increase the overall properties of this high‐entropy carbide ceramic (HECC) through introducing SiC particle (SiCP). To this end, a series of (NbTaZrW)C–xSiC ceramic composites (x = 0/5/15/30/50 vol.%) were fabricated using spark plasma sintering (SPS), their microstructure and mechanical properties were characterized. Our results reveal a grain refinement effects of SiCP, an agglomeration of SiCP with (1 0 0) plane preferentially perpendicular to the SPS‐pressing direction and the formation of a transition region with various stoichiometric ratio of (NbTaZrW)xC1−x in the (NbTaZrW)C–SiCP vicinity. The elastic modulus, microhardness, and flexural strength of the HECCs show tight positive relations with the SiCP content and the beneficial effect of SiCP to the fracture toughness of (NbTaZrW)C becomes evident once the content of SiCP reaches 30 vol.%. Altogether, (NbTaZrW)C–50%SiC, which has a microhardness of 22 GPa, a flexural strength of 455 MPa, and an indentation fracture toughness of 6.54 MPa m1/2, presents the optimal combination of mechanical properties among the investigated composites. Mechanistically, the strengthening effect of SiCP introduction arises from the intrinsic high hardness of SiCP and the SiCP‐induced grain refinement and the toughening effect is mainly associated with crack bridging mechanism. [ABSTRACT FROM AUTHOR]

Objectives: To estimate the coverage and willingness of pneumococcal vaccination and further explore the influencing factors of vaccination willingness among people in mainland China.Methods: Literature searches were conducted independently by two researchers in English- and Chinese-language databases from database inception to 6 October 2021. A random-effects meta-analysis model was used to derive summary vaccination coverage and willingness. Predefined subgroup analysis and meta-regression were performed to explore the sources of heterogeneity.Results: A total of 97 studies were included in this meta-analysis. The summary vaccination coverage in 76 included studies was 21.7% (95% confidence interval [CI]: 17.2%-26.5%). Subgroup analysis shows that the summary coverage was 29.0% (95% CI, 20.4%-39.1%) among the permanent residents and 20.7% (95% CI, 12.4%-35.9%) among the floating residents. The eastern and central regions presented higher coverage than the western region. Notable differences were observed between the various study populations. A total of 27 studies provided an estimation of vaccination willingness, with a summary willingness of 51.2% (95% CI, 40.4%-61.9%). In subgroup analysis, the summary willingness was 57.9% (95% CI, 48.3%-67.2%) in urban areas and 52.3% (95% CI, 40.8%-63.8%) in rural areas. Parents with children and people with a history of pneumonia were more willing to be vaccinated than the elderly. Recommendations by family members and physicians, previous pneumococcal and influenza vaccination, perceived vaccination effectiveness and severity of disease and a history of pneumonia contributed to vaccination willingness.Conclusions: Compared to global estimates and other countries, pneumococcal vaccination coverage and willingness are at a lower level in mainland China. Recommendations for vaccination by family members and doctors, a history of vaccination and the perception of pneumonia and vaccination are associated with greater willingness to be vaccinated. [ABSTRACT FROM AUTHOR]

This paper examines the issue of earning management in companies with equity incentives from two dimensions: management manipulation of the intensity of R&D and accounting treatment by using a sample of Shanghai and Shenzhen listed companies in China from 2014 to 2019. We find that in order to depress the benchmarks and exercise prices for the performance appraisal of the equity incentive covenants, managers not only conduct accrual earnings management by expensing R&D expenditure but also increase the intensity of R&D investment for real earnings management. We also find that companies with equity incentives where managers have more power are more inclined to opt for the more concealed means of real earnings management and try to avoid accrual earnings management, which may entail higher regulatory costs and greater litigation risk with tightening accounting regulations. Our findings contribute to expanding the literature on earnings management of companies with equity incentives and provide empirical evidence for regulators to implement 'precision regulation' on equity incentives and earnings management. [ABSTRACT FROM AUTHOR]

In recent years, the rapid development of the Internet of Things (IoT) technology has provided a strong technical support for the technological transformation of the logistics industry. The informatization development of logistics industry increasingly relies on the Internet of Things technology represented by Radio Frequency Identification (RFID) technology. These technologies lead the whole business process to optimize the business process in the direction of accurate, efficient and real‐time. In order to solve the problem that the reader cannot identify the label information correctly due to the phenomenon of data collision in the application of RFID technology, this paper proposes an anti‐collision algorithm based on Slotted Random Regressive‐style Binary Search Tree (SR‐RBST). Based on Slotted ALOHA (SA) the method proposed in this paper uses the Regressive‐style Binary Search Tree (RBST) to process the RFID labels in the collision time slot. With the same size of tags, the SR‐RBST algorithm needs less total time slot and has higher efficiency and shorter identification time, while with the increase of the number of tags, the SR‐RBST anti‐collision algorithm has more obvious advantages. The SR‐RBST algorithm effectively improves the time slot utilization efficiency of the system. [ABSTRACT FROM AUTHOR]

This study examines the joint supervision of auditors and sponsors in a sample of private placements on the Shanghai and Shenzhen stock markets from 2006 to 2019. We observe variation in the inhibitory effect of earnings management and inefficient investment based on the combination of intermediaries with different reputations. We find that auditors exert a strong inhibitory effect on earnings management while sponsors are best positioned to suppress inefficient investment. Furthermore, this study enriches the existing supervisory literature and provides insights to further improve the relationship between auditors and sponsors in the context of China's unique registration system. [ABSTRACT FROM AUTHOR]

The energy density of batteries with lithium cobalt oxide (LCO) can be maximized by increasing the cut‐off voltage to approach the theoretical capacity limit. However, it is not realized in the practical applications due to the restricted cycle life caused by vulnerable cathode surface in deep delithiation state, where severe side reactions, oxygen/cobalt loss and structure degradation often happen. Here, an outside‐in oriented nanostructure on LiCoO2 crystals is fabricated. The outer electrochemically stable LiF and Li2CoTi3O8 particles perform as physical barrier to prevent damage of both cathodes and electrolytes, while the inner F doping promote Li ions diffusivity and stabilize the lattice oxygen. With the spinel‐like transition layer between them, a solid and complete lithium‐ion transport channel generation along the lithium concentration gradient. Under the protection from this structure, the LiCoO2 withstand the high voltage of 4.6 V and the LCO/graphite pouch full cell with high loading density exhibits 81.52% energy density retention after 135 cycles at 4.5 V. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV)‐durable organic solar cells (OSCs) are realized by incorporating a CdSe@ZnS quantum dots (QDs)‐modified PEDOT:PSS hole extraction layer (HEL). The use of the CdSe@ZnS QDs‐modified PEDOT:PSS HEL has an obvious improvement in UV‐durability of OSCs. A more than 50% reduction in the power conversion efficiency (PCE) is observed for a (PM6:Y6)‐based control OSC with a PEDOT:PSS HEL, under the 1000 min accelerated UV (365 nm, 16 W) aging test. Whereas a much reduced reduction of 35% in PCE is observed for the OSCs with a CdSe@ZnS QDs‐modified PEDOT:PSS HEL, under the same accelerated UV aging test condition. Results reveal that the Coulombic attraction between the PEDOT units and PSS chains in the PEDOT:PSS layer is disturbed due to the interaction between hydroxyl ligands of the CdSe@ZnS QDs and PSS through hydrogen bond, leading to an increase in the electric conductivity in PEDOT:PSS layer through transforming PEDOT quinoid structure to expanded‐coil structure. The use of the CdSe@ZnS QDs‐modified PEDOT:PSS HEL also favors the efficient operation of the nonfullerene acceptor (NFA)‐based OSCs through maintaining a high built‐in potential across the bulk heterojunction. The results demonstrate the importance of the interface engineering to alleviate UV light‐induced degradation processes of NFA‐based OSCs. [ABSTRACT FROM AUTHOR]

This article was to explore the adoption value of deep learning combined with computed tomography (CT) imaging omics in the prediction of metastatic lymph nodes of nasopharyngeal carcinoma (NPC). An end‐to‐end neural network architecture was designed based on the fully convolutional neural network (FCNN), which was applied to the CT image analysis of 52 patients with lymphatic metastasis and 36 patients without lymphatic metastasis. Patient's lymph node volume (V), the largest cross‐sectional shortest diameter (d‐value), and other macro characteristics were recorded. The microscopic features of its CT imaging omics were extracted. Moreover, receiver operating characteristic (ROC) curve was utilized to analyse the prediction performance (accuracy, area under the curve [AUC], and Youden index) of each feature for lymphatic metastasis. The results showed that the lymph node volume (4.37 ± 0.67) and the shortest diameter of the largest cross section (12.35 ± 2.31) of patients with lymph node metastasis were greatly larger than those without lymph node metastasis (1.84 ± 0.65, 7.98 ± 2.04) (P < 0.05). There were five features that met the conditions of AUC > 0.7 and Yoden index>0.5, including lymph node volume (AUC area 0.945, Youden index 0.597), the shortest diameter of the largest cross section (AUC area 0.746, Youden index 0.539), Surface Area Density (AUC area 0.809, Youden index 0.552), Compactness1 (AUC area 0.751, Youden index 0.537), and Convex Hull Volume (AUC area 0.751, Youden index 0.537). The AUC of V+ Surface Area Density + Compactness1 + Convex Hull Volume was 0.876, and the prediction accuracy was 92.11%. In short, the prediction model composed of the macroscopic features of CT images and some imaging omics features based on deep learning showed high accuracy and AUC for the prediction of NPC metastatic lymph nodes. Moreover, V + Surface Area Density + Compactness1 + Convex Hull Volume can be used as the optimal feature combination model for predicting NPC lymphatic metastasis. [ABSTRACT FROM AUTHOR]

Following the reform of shareholder structures in China, the country's listed companies have seen a boom in asset injection using private equity placements. However, because of continuing weaknesses in corporate governance structures and accounting regulations on related‐party transactions, it is possible for controlling shareholders to 'tunnel' listed companies through unsound private placements. We find that manipulation of the discount rate offered in private placements, accompanied by earnings management behaviour, is used by controlling shareholders to 'tunnel' listed companies during the private placement and asset‐injecting process. [ABSTRACT FROM AUTHOR]

In order to tackle the marine practical constraints, for example the actuator faults, the dead‐zone input, an improved composite adaptive neural control algorithm is proposed for dynamic positioning vehicles in presence of the unknown external disturbances. In the algorithm, the robust neural damping technique is employed to remodel the system model uncertainty and suppress the external interference. As for the dead‐zone input, the dead‐zone inverse model is constructed to derive the corresponding compensating terms. That could effectively release the constraints from the actuator faults and the dead‐zone non‐linearity. Furthermore, for merits of the composite intelligent learning method, one designs the serial‐parallel estimation model to estimate the related velocity variables. The corresponding prediction error could be applied in the design of adaptive law. That could effectively improve the accuracy of parameter estimation and facilitate the robustness of the closed‐loop system. The semi‐global uniformly ultimately bounded stability is guaranteed for all error signals in the closed‐loop system by utilizing the Lyapunov theory. Finally, the validity of the proposed algorithm is demonstrated through the simulation experiments. [ABSTRACT FROM AUTHOR]

The industrial application of lithium metal anode requires less side reaction between active lithium and electrolyte, which demands the sustainability of the electrolyte‐induced solid‐electrolyte interface. Here, through a new diluted lithium difluoro(oxalato)borate‐based (LiDFOB) high concentration electrolyte system, it is found that the oxidation behavior of aggregated LiDFOB salt has a great impact on solid‐electrolyte interphase (SEI) formation and Li reversibility. Under the operation window of Cu/LiNi0.8Co0.1Mn0.1O2 full cells (rather than Li/Cu configuration), a polyether/coordinated borate containing solid‐electrolyte interphase with inner Li2O crystalline can be observed with the increasing concentration of salt, which can be ascribed to the reaction between aggregated electron‐deficient borate species and electron‐rich alkoxide SEI components. The high Li reversibility (99.34%) and near‐theoretical lithium deposition enable the stable cycling of LiNi0.8Co0.1Mn0.1O2/Li cells (N/P < 2, 350 Wh kg−1) under high cutoff voltage condition of 4.6 V and lean electrolyte condition (E/C ≈ 3.2 g Ah−1). [ABSTRACT FROM AUTHOR]

Authenticated key exchange protocol is widely applied in the Internet services. Lattice‐based key exchange protocols turn out to be quantum‐resistant and hence have attracted tremendous attention. A lattice‐based explicit authenticated key exchange protocol is constructed by combining an IND‐CPA key encapsulation mechanism with a strong EUF‐CMA digital signature under the message‐recovery mode. Concrete parameter specifications are suggested under the 102 and 218 bits post‐quantum security, respectively. Compared with the implicit authenticated key exchange derived directly from the key encapsulation mechanism, our proposals reduce the communication costs by 21.7% and 25.7%, respectively, under the same post‐quantum security level. Rough analysis shows that the proposals also obtain some advantages over previous constructions in term of computational efficiency. Moreover, our scheme achieves perfect forward secrecy while the original scheme only satisfies weak forward secrecy. [ABSTRACT FROM AUTHOR]

Several heuristic procedures to estimate the rotor position of interior permanent magnet synchronous motors (IPMSM) via signal injection have been reported in the application literature, and are widely used in practice. These methods, based on the use of linear time-invariant (LTI) high-pass/low-pass filtering, are instrumental for the development of sensorless controllers. To the best of authors' knowledge, no theoretical analysis of these methods has been carried out. The objectives of this note are (i) to invoke some recent work on the application of averaging techniques for injection-based observer design to develop a theoretical framework to analyse the LTI filtering used in sensorless methods and (ii) to propose a new method that on the one hand ensures improved accuracy and on the other hand can be related to the current filtering technique. An additional advantage of the new method is that it relies on the use of linear operators, implementable with simple computations. The effectiveness of the proposed scheme is assessed by experiments on an IPMSM platform driven by a 521 V DC bus with a 5-kHz pulse-width modulation. [ABSTRACT FROM AUTHOR]

As a nonthermal sterilization technology, electron‐beam irradiation (EBI) has attracted great interests for microbial inactivation in food preservation. In this study, the inactivation of inoculated Listeria innocua, natural microbiota, and quality of fresh noodles treated by EBI during refrigerated storage were evaluated. Results showed that the initial L. innocua population (6.38 log CFU/g) was significantly reduced to an undetectable level by treatment with 3.0 kGy EBI. Moreover, treatment with 3 kGy EBI significantly reduced the initial total bacteria counts and fungal counts (mold and yeast) from 5.66 and 3.15 log CFU/g to 2.90 and 2.11 log CFU/g, respectively. However, along with the storage process, the inoculated L. innocua and natural microbiota were recovered resulting in the increased populations of the spoilage microorganisms. Increasing the dose of EBI to 4.0 kGy or 5.0 kGy, the L. innocua population was inhibited to the undetectable level and the microbiological quality of the fresh noodles was kept in the acceptable level during the 28 day storage. In addition, changes of the physicochemical indicators including pH value, color, cooking characteristics, texture, and sensory of fresh noodles treated with EBI were delayed during storage. These results reveal that EBI treatment can improve the microbiological safety and shelf life of fresh noodles without impairing quality. [ABSTRACT FROM AUTHOR]

Oral folate is currently the most common treatment for hyperhomocysteinemia (HHcy), which seriously threatens human health, but its efficacy is unsatisfactory. Betaine‐homocysteine methyltransferase (BHMT) is a key enzyme that regulates Hcy metabolism. We investigated the association between the BHMT rs3733890 and the efficacy of oral folate therapy for HHcy in the Chinese Han population and analysed the effects of gene–environmental interactions on the efficacy. Blood samples were collected from 1071 eligible patients at baseline, and these individuals received subsequent folate treatment for 90 days. A total of 638 patients included in the final analysis were grouped into the treatment success group or the treatment failure group based on posttreatment Hcy levels. Hcy concentrations were measured by fluorescence polarization immunoassay. Time‐of‐flight mass spectrometry (MassArray system) was used to assess the genotype of BHMT rs3733890. Stratified analyses based on additive models and generalized multifactor dimensionality reduction were used to explore gene–environmental interactions. The genotype distribution presented distinct differences in the two groups. The mutant genotype and allele had significantly increased risk of treatment failure (p < 0.05). Furthermore, synergistic effects of the BHMT rs3733890 polymorphism with environmental risk factors (smoking, drinking, past history) on the efficacy of therapy were also found. However, future, large well‐designed studies, as well as mechanistic studies, are still needed to validate our findings. [ABSTRACT FROM AUTHOR]

Based on the improved radial basis function (RBF) neural networks, the distributed three‐dimension formation control scheme in the presence of dynamic uncertainties is studied for non‐linear multi‐agent systems with time delay. A virtual leader which tracks the desired signal is followed by all agents adaptively. Linear reduced‐order observers are designed on the basis of absolute and local state errors of each agent. The local state error and absolute state error are generated between neighbouring agents and each individual agent in formation, respectively. The time delay for each agent in the formation can be offset by designing a Lyapunov function, which can simplify the controller design. To deal with non‐linear dynamic uncertainties and unavoidable disturbance, improved RBF neural networks are employed. In comparison with traditional RBF neural networks, improved RBF neural networks can provide better convergence performance. Subsequently, the formation controller is designed and the stability of the systems is validated by using a new Lyapunov function. Numerical simulation is conducted to demonstrate the effectiveness of the proposed method for non‐linear multi‐agent time‐delay systems. [ABSTRACT FROM AUTHOR]

In this study, a new adaptive controller is introduced for the induction motors (IMs) based on immersion and invariance (I&I) technique. The dynamics of the IM system are perturbed by some disturbances such as time‐varying rotor resistance and load torque. Accordingly, an adaptive controller is designed and the uncertain parameters are online estimated. The adaptation laws are obtained from the stability analysis based on I&I method. The simulation results verified the effectiveness of the proposed control method. It is revealed that the outputs of the IM could track the desired signals in the presence of the mentioned disturbances. Also, the results are compared with the conventional control methods and it is concluded that the proposed control approach resulted in better performance. [ABSTRACT FROM AUTHOR]

Plant litter inputs can promote the decomposition of soil organic matter (OM) through the priming effect (PE). However, whereas leaf litter chemistry has long been identified as the primary driver of litter decomposition within biomes world‐wide, little is known about how litter chemical traits influence the occurrence and strength of the PE.Here, we studied the effects of 15 co‐occurring C3 leaf litters of contrasting chemistry on C4 soil respiration by analysing changes in 13C natural abundance during early and later stages of litter decomposition (up to 125 days).Besides an apparent PE of 16% in the first 3 days, soil C respiration was increased by 24% on average with leaf litter addition in the initial stage of decomposition (4–26 days) and by 8% at later stages (27–125 days). Most interestingly, soil PE related well to initial litter chemistry and the dominant factors influencing the magnitude of the PE changed with decomposition stage. In the early stage of decomposition, litter leachate C content and litter hemicellulose concentration were positively correlated with the strength of the PE, whereas tannin concentration was negatively associated with soil PE. Together, tannin and hemicellulose explained half of the observed variation in the PE (R2 = 0.58). In the later phase of decomposition, lignin and lignin:N ratios were negatively related to the PE, whereas Ca, K and Mg concentrations were positively related to the PE; lignin alone gave the best prediction of the PE (R2 = 0.58) at later decomposition stages.Our findings provide evidence that the magnitude and direction of the PE is influenced by the chemistry of OM inputs and suggest that, as decomposition proceeds differently among litter of contrasting chemistry, litters can also have variable effect on soil PE through time. The predictive power of litter chemical traits on soil PE opens new perspectives for improving our mechanistic understanding of soil PE and improving our abilities to model soil C dynamics at variable scales. A plain language summary is available for this article. [ABSTRACT FROM AUTHOR]

The response of soil organic carbon (SOC) decomposition to global warming is a potentially major source of uncertainty in climate prediction. However, the magnitude and direction of SOC cycle feedbacks under climate warming remain uncertain because of the knowledge gap about the global‐scale spatial pattern and temperature sensitivity (Q10) mechanism of SOC decomposition.Here, we collected data of Q10 and corresponding soil variables from 81 peer‐reviewed papers using laboratory incubation to explore how Q10 varied among different ecosystems at the global scale and whether labile and recalcitrant SOC pools had equal Q10 values.Q10 with a global average of 2.41 substantially varied among different ecosystems, ranging from the highest in cropland soils (2.76) and the lowest in wetland soils (1.84). Hump‐shaped correlations of Q10 values with the maximum at SOC = 190 g/kg and the minimum at clay = 37% were observed. However, the main influencing factors of Q10 differed among various ecosystems. Q10 values showed a clear decrease with increasing incubation temperature but no significant decrease above 25°C. In general, labile SOC was less sensitive than recalcitrant SOC to warming. Structural equation model analyses showed that total N and SOC accounted for 53% and 46%, respectively, of the variation in Q10 of labile SOC and recalcitrant SOC. This finding suggested that Q10 values of labile and recalcitrant SOC pools had different controlling factors.Our findings highlighted the importance of Q10's variations in ecosystem types and the response of recalcitrant SOC to warming in predicting the soil C cycling and its feedback to climate change. Therefore, ecosystem type and difference in Q10 of labile and recalcitrant SOC should be considered to precisely predict the soil C dynamics under global warming. A plain language summary is available for this article. Plain Language Summary [ABSTRACT FROM AUTHOR]

This study deals with the protocol design for achieving robust global consensus tracking of multi‐agent systems. Agent dynamics are described as general linear systems with actuator saturation and input additive uncertainties and disturbances. Via developing a scheduled low‐and‐high gain design technique, the state feedback protocol is proposed, under which global consensus tracking and disturbance rejection for such systems can be achieved under the mild assumptions on agent dynamics and network topology. This result is further extended to the case of the reduced‐order observer‐based protocol design, with the help of the special coordinate basis approach. Finally, the advantages of the proposed protocols are illustrated by a numerical simulation. [ABSTRACT FROM AUTHOR]

In this note, a novel adaptive constrained control algorithm is proposed for dynamic positioning vessels in the presence of input amplitude and rate saturations. In the scheme, both kinematics and kinetics loops are augmented by the auxiliary system to deal with the saturation impact. Meanwhile, for merits of the command filters and minimal leering parameter technique, the cumbersome analytic derivatives of the virtual control law need not be required in the control design, and only two adaptive parameters are updated online to stabilise the effect of the model uncertainty and the external disturbance for each subsystem. Using the Lyapunov theory, the semi‐global uniformly ultimately bounded is proved for the closed‐loop system. The effectiveness and robustness of the proposed algorithm are demonstrated by the numerical example in the presence of the simulated marine disturbance. [ABSTRACT FROM AUTHOR]

Prostate cancer (PCa) often recurs as incurable castration-resistant prostate cancer (CRPC) after the failure of androgen deprivation therapy. CRPC development relies on androgen receptor (AR) signaling. The IL6/STAT3 pathway is also a key driver of CRPC. The crosstalk between IL6/STAT3 and the AR pathways provides opportunities to explore next-generation agents to treat PCa. Through screening of around 600 natural compounds in our newly established prostate tumorigenesis model, potential STAT3 signaling inhibitors were found and additionally examined for effects on AR signaling. The small molecular compound 154 exhibited dual effects on IL6/STAT3 and AR pathways. We show here that compound 154 inhibits AR and STAT3 transcriptional activity, reduces the expression of phosphorylation of STAT3 (Y705) and downregulates the mRNA levels of AR target genes. Compound 154 also inhibits protein expression of AR and AR splice variants (ARv567es and AR-V7) without altering AR mRNA levels. Compound 154 binds to AR directly, but not to STAT3 and is identified as an antagonist of the AR amino-terminal domain (NTD) by disrupting protein-protein interactions between STAT3 and the AR NTD. Moreover, compound 154 does not reduce AR nuclear translocation. Compound 154 possesses the potential to become a leading compound in novel therapies against CRPC. [ABSTRACT FROM AUTHOR]

A two‐degree‐of‐freedom consensus scheme is investigated for fractional‐order multi‐agent systems with time delay. The two‐degree‐of‐freedom protocol including the individual controllers and the coupling controllers can realise the global tasks and improve consensus performance. Based on such a protocol, a closed‐loop multi‐input multi‐output framework in frequency domain is established. Then the multi‐agent system is decoupled into several subsystems with respect to the eigenvalues of the Laplacian matrix. For each subsystem, the robust stabilising region of the individual controller satisfying H∞ index is obtained on the basis of the improved D‐partition method. The controller parameters chosen in the region can provide robustness for the individual agent. The parameters of the coupling controller that ensure fast consensus are determined by first deriving the stabilising region and then searching for the fastest consensus speed in the obtained region. The two‐degree‐of‐freedom structure can trade off the consensus performance and disturbance rejection and is applicable to arbitrary‐order multi‐agent systems with time delay including the fractional‐order system and the integer‐order system. The two‐degree‐of‐freedom consensus controller satisfying other performance criteria can also be designed based on the resultant stabilising region. The simulation results verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The study addresses the consensus problem of linear time invariant (LTI) multi‐agent systems with constant input delay and matched external disturbances by using relative output information. First, distributed disturbance observers are constructed to estimate the disturbances generated by linear exosystems with unknown initial conditions. Next, a disturbance observer‐based predictor feedback control law is developed for each agent to realise consensus disturbance rejection in the presence of input delay. Then, a linear matrix inequality‐based control design algorithm is given to determine the satisfactory control parameters. It is proved that state consensus can be achieved for both leaderless and leader–follower networks in the presence of large input delay and matched disturbances under the control scheme. Finally, a simulation example is provided to validate the theoretical results. [ABSTRACT FROM AUTHOR]

This study addresses the distributed H∞ and H2 consensus control problems for multi‐agent systems with general integrator dynamics and undirected topology. First, based on the frequency domain description of linear multi‐agent systems, a sufficient and necessary condition is imposed on each controller to achieve consensus. Second, both H∞ and H2 optimal controllers are computed analytically according to the corresponding performance indices. The novel controllers not only can optimise the reference tracking performance but also has a simple tuning way to trade off the nominal performance and robustness. Finally, by application to the formation control of autonomous surface vessels shows the effectiveness of the proposed two control strategies. [ABSTRACT FROM AUTHOR]

This study addresses the networked control problem for event‐triggered systems with quantisation effect and actuator fault. A new type of finite‐level dynamic logarithmic quantiser is proposed here. Firstly, when the actuator is subjected to deterministic fault and time delay occurs in the network between the sensor and the controller, stability analysis and stabilisation of the system are accomplished. Secondly, suppose the actuator is subjected to stochastic fault and there is packet dropout in the network between the sensor and the controller, the asymptotic stability of the system is analysed, and a mean‐square feedback controller is designed. Finally, simulation studies are made to verify the effectiveness of the presented method. [ABSTRACT FROM AUTHOR]

This study proposes an adaptive non‐singular integral terminal sliding mode control (ANITSMC) scheme for trajectory tracking of autonomous underwater vehicles (AUVs) with dynamic uncertainties and time‐varying external disturbances. The ANITSMC is first proposed for a first‐order uncertain non‐linear dynamic system to eliminate the singularity problem in conventional terminal sliding mode control (TSMC) and avoid the requirement of the bound information of the lumped system uncertainty. The time taken to reach the equilibrium point from any initial error is guaranteed to be finite. The proposed ANITSMC is then applied to trajectory tracking control of AUVs. It guarantees that the velocity tracking errors locally converge to zero in finite time and after that the position tracking errors locally converge to zero exponentially. The designed ANITSMC of AUVs avoids the requirement of the prior knowledge of the lumped system uncertainty bounds as opposite to the existing globally finite‐time stable tracking control (GFTSTC), provides higher tracking accuracy than the existing GFTSTC and adaptive non‐singular TSMC (ANTSMC) and offers faster convergence rate and better robustness against dynamic uncertainties and time‐varying external disturbances than the adaptive proportional‐integral sliding mode control (APISMC). Comparative simulation results are presented to validate the superiority of the ANITSMC over the APISMC. [ABSTRACT FROM AUTHOR]

An optimal disturbance rejection controller design method is put forward analytically for the synchronised output regulation of time‐delayed multi‐agent systems (MAS). All kinds of linear MAS can be described by a novel block diagram based on transfer functions in a unified framework. For each subsystem without intercommunication, the optimal output, input and balancing output–input load disturbance rejection controllers are designed independently. A filter is used to be in series with each controller to not only stabilise the whole systems but also achieve a tradeoff between nominal performance and robustness by adjusting a single tuning parameter. The proposed distributed H2 controllers calculated by algebraic solution perform better capacity of disturbance attenuation than the conventional given‐structured protocols. Two simulation examples demonstrate the validity of the new algorithm. [ABSTRACT FROM AUTHOR]

Cooperative output regulation is a general framework, which considers output synchronisation, homogenisation and disturbance rejection simultaneously. To be an extension, this study divides the lumped disturbance into two parts, namely, local disturbance which is slow‐varying, mismatched and non‐linear, and global disturbance generated by an autonomous linear system. Generalised extended state observers (GESOs) are constructed to estimate the local states, the local disturbances and the global disturbance simultaneously. Observer‐based controllers are designed to realise cooperative output regulation in the presence of mismatched uncertainties. In control design, a linear matrix inequality‐based design methodology is proposed to get the exponentially convergent GESO with guaranteed decay rate. A simulation example is then shown to validate the theoretical results. [ABSTRACT FROM AUTHOR]

This study presents a new observer‐based electronic line‐shafting (ELS) control scheme as motion synchronisation solution for motor drives in the industrial manufacturing process. To achieve better speed control performance for each ac motor drive, a sliding mode controller is proposed. This controller is designed based on a non‐linear reaching law, which helps to settle the reaching time/chattering dilemma in the conventional sliding mode control (SMC) approach. In addition, a sliding mode observer is proposed to estimate lumped disturbances for the motor drives. Disturbance estimation results are fed forward as compensation parts for the SMC controller; in the meantime, they are transmitted to the virtual line‐shafting drive to accurately reflect total system disturbances, thus to achieve high motor speed synchronisation precision. Effectiveness of the proposed ELS control scheme is verified by simulation results. [ABSTRACT FROM AUTHOR]

The surfactant structure-performance relationship and application properties in enhanced oil recovery (EOR) for binary mixtures of anionic and cationic surfactants are presented and discussed. A polyoxyethylene ether carboxylate anionic surfactant was blended with a quaternary ammonium chloride cationic surfactant and tested for a high-temperature, low-salinity, and high-hardness condition as found in an oil reservoir. These mixtures were tailored by phase behavior tests to form optimal microemulsions with normal octane (n-C8) and crude oil having an API gravity of 48.05°. The ethoxy number of the polyoxyethylene carboxylate anionic surfactant and the chain length of the cationic surfactant were tuned to find an optimal surfactant blend. Interfacial tensions with n-C8 and with crude oil were measured. Synergism between anionic and cationic surfactants was indicated by surface tension measurement, CMC determination, calculation of surface excess concentrations and area per molecule of individual surfactants and their mixtures. Molecular interactions of anionic and cationic surfactants in mixed monolayers and aggregates were calculated by using regular solution theory to find molecular interaction parameters β and β . Morphologies of surfactant solutions were studied by cryogenic TEM. The use of binary mixtures of anionic/cationic surfactants significantly broadens the scope of application for conventional chemical EOR methods. [ABSTRACT FROM AUTHOR]

Nitrogen addition has been shown to affect plant litter decomposition in terrestrial ecosystems. The way that nitrogen deposition impacts the relationship between plant litter decomposition and altered soil nitrogen availability is unclear, however. This study examined 18 co-occurring litter types in a subtropical forest in China in terms of their decomposition (1 yr of exposure in the field) with nitrogen addition treatment (0, 0.4, 1.6, and 4.0 mol·N·m−2·yr−1) and soil fauna exclusion (litter bags with 0.1 and 2 cm mesh size). Results showed that the plant litter decomposition rate is significantly reduced because of nitrogen addition; the strength of the nitrogen addition effect is closely related to the nitrogen addition levels. Plant litters with diverse quality responded to nitrogen addition differently. When soil fauna was present, the nitrogen addition effect on medium-quality or high-quality plant litter decomposition rate was −26% ± 5% and −29% ± 4%, respectively; these values are significantly higher than that of low-quality plant litter decomposition. The pattern is similar when soil fauna is absent. In general, the plant litter decomposition rate is decreased by soil fauna exclusion; an average inhibition of −17% ± 1.5% was exhibited across nitrogen addition treatment and litter quality groups. However, this effect is weakly related to nitrogen addition treatment and plant litter quality. We conclude that the variations in plant litter quality, nitrogen deposition, and soil fauna are important factors of decomposition and nutrient cycling in a subtropical forest ecosystem. [ABSTRACT FROM AUTHOR]

In this study, the authors mainly focus on the event‐triggered control design problem of networked control systems (NCSs) with dynamic quantisation and fault. The research contents are divided into two parts. The first part assumes that quantised measurements of the state are available, asymptotic stability analysis and feedback controller design of the event‐triggered NCSs with constant sensor fault and actuator fault are accomplished. The second part assumes that quantised measurements of the input are available, stochastic actuator fault, which is modelled by the Bernoulli distributed white sequence is considered in this situation, and a robust feedback controller is designed. At the end, numerical examples are given to illustrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

In this study, the authors investigate distributed model predictive control for polytopic uncertain systems subject to actuator saturations and packet dropouts with time‐varying probabilities in controller‐to‐actuator channels. For the sake of less computational efforts and a flexible system structure, the global system is decomposed into several lower‐dimensional subsystems and the subsystems optimise a global performance function in parallel. A novel augmented distributed controller model is proposed to describe both the actuator saturations and packet dropouts in one unified expression by adopting a stochastic variable taking the value 1 or 0 with time‐varying probabilities and accordingly a new result is obtained. By placing the saturated linear feedback law into the convex hull of a group of linear feedback laws, the distributed controller for each subsystem is obtained from the solution of the convex optimisation problem involving linear matrix inequalities. A numerical example is supplied to demonstrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]

Output regulation is a general framework, for it not only can achieve closed‐loop stability, but also can realise asymptotic tracking and disturbance rejection. Within this framework, the authors consider the containment problem of heterogeneous linear multi‐agent systems with directed graphs. Via dynamic compensator techniques, the containment problem can be converted into cooperative output regulation problem. Moreover, they artfully construct regulation equations, whose solutions are also given. Adaptive protocols are proposed here by assigning a time‐varying coupling weight to each node. Unlike most existing protocols that depend on certain global information, protocols presented in this paper are independent of any global information, and hence are fully distributed. By combining the compensator technique with adaptive control, they propose the distributed dynamic adaptive state feedback and adaptive output feedback protocols for driving followers into the moving convex hull spanned by leaders. The obtained results are applied to the containment control of a network of heterogeneous agents, where the followers are described by mass‐damper spring systems, and the leaders are specified by harmonic oscillators. [ABSTRACT FROM AUTHOR]

This study considers the observer‐based consensus tracking problem of linear multi‐agent systems with input saturation. Existing observer‐based consensus protocols are designed based on an undirected graph, and need global information, such as the network size or eigenvalue information of the Laplacian matrix. In this study, based on only the agent dynamics and the relative outputs of neighbouring agents, an adaptive consensus protocol is proposed by assigning a time‐varying coupling weight to each node, and this protocol is independent of any global information and hence is fully distributed. Under the assumptions that each agent is asymptotically null controllable with bounded controls and detectable, and the topological graph has a directed spanning tree with the leader as the root node, semi‐global observer‐based consensus tracking of multi‐agent systems can be reached despite actuator saturation occurring. The results are applied to consensus tracking control of two‐mass‐spring systems, which are well‐known models for vibration in many mechanical systems. [ABSTRACT FROM AUTHOR]

This study addresses the finite‐frequency robust feedback controller design problem against actuator faults for linear parameter‐varying systems. First, a general model of actuator faults is presented. Then, sufficient conditions for the existence of the state‐feedback controller are obtained by using generalised Kalman–Yakubovich–Popov lemma and projection lemma, which guarantee that the closed‐loop system satisfies robustness performance in a finite‐frequency domain and is stable for both faults free and actuator faults. In addition, by introducing a state feedback gain, the non‐convexity conditions of the output‐feedback gain are derived. An iterative linear matrix inequality algorithm is proposed in this study to get the solution. The performances of the proposed reliable controller schemes are illustrated by two examples. [ABSTRACT FROM AUTHOR]