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This work addresses the verification of current-state opacity with respect to a real-time observation generated from time-dependent systems. The secret behavior of a time-dependent system is defined as a set of states in a time labeled Petri net. The current-state opacity of a real-time observation means that a given secret remains opaque to the intruder who can partially observe the system behavior in the framework of a time labeled Petri net at a given time instant. We introduce a novel directed graph, called a parallel state class graph, to represent the parallel evolution of time-dependent systems exhaustively. Based on the parallel state class graph, we design an algorithm for the construction of a critical observer and show that the current-state opacity of a real-time observation in time labeled Petri nets can be efficiently solved by the critical observer. This approach is computationally competitive since the critical observer can be constructed by solving a number of linear programming problems. Note to Practitioners—In computer-integrated real-time systems, their correctness-related properties usually depend on time constraints. System opacity guarantees that particular system information cannot be disclosed or inferred by external observers, which is a generalization of many information flow properties associated with system safety, particularly in aerospace, automotive, and healthcare domains. This research addresses the verification problem of this property for a discrete event system modeled with time labeled Petri nets. By developing a graph-theoretical structure that can be readily managed by security engineers, a type of diagram called a critical observer is derived which is able to detect the privacy of the system at a given time instant. This research provides a systematic and efficient approach for practitioners to check a desired privacy strategy of time-constrained safety systems.

Cavitation erosion is a pervasive issue in hydraulic machinery and ocean engineering, characterized by the collapse of bubbles, micro-jetting, and impact erosion, all exhibiting strong transient, microscale, and fluid–solid coupling features. Understanding these phenomena is essential for elucidating the mechanisms behind erosion and for developing strategies to prevent wear damage. Recognizing the limitations of conventional numerical methods, this study employs the smoothed particle hydrodynamics (SPH) method to develop a fluid–solid coupling model that simulates cavitation erosion at the bubble scale. The Lagrangian and mesh-free nature of SPH make it well-suited for tracking the transient processes of asymmetric bubble collapse, jet formation, and the subsequent impact on elastic–plastic materials. A comprehensive fluid–solid coupling SPH model is constructed, encompassing bubbles, surrounding liquids, and elastic–plastic materials. This model includes a compressible multiphase SPH approach for simulating the interaction between highly compressible bubbles and liquids. To address gas phase over-compression during bubble collapse, a modified particle regeneration technique (PRT) is introduced, allowing for automatic adjustment of particle resolution in the gas domain as it expands or compresses. For the solid simulation, an elasto-plastic constitutive model and a failure model are integrated into the SPH framework to describe material deformation and failure due to microjet impacts. These enhancements enable the simulation of the entire cavitation erosion process within a unified, mesh-free context. The SPH model is validated through simulating bubble collapse and jetting induced by shock waves. It is then applied to investigate the dynamics of cavitation erosion near both rigid and elastic–plastic materials, providing quantitative analysis of the erosion process. The outcomes of this research contribute significantly to our understanding of cavitation erosion mechanisms and offer a robust computational tool for predicting and mitigating erosion damage in related engineering applications.

Open vascular reconstructions (OVR), including bypass grafts and dialysis access, are standard treatments for cardiovascular and renal diseases. Unfortunately, OVR often fail largely due to intimal hyperplasia (IH), and there are no clinical methods to prevent this complication. Perivascular drug administration during OVR presents a promising strategy for IH suppression. However, durations of drug release from carriers are generally short whereas sustained efficacy is essential for clinical success. This raises a critical question in clinical translation: can IH suppression be realistically maintained long-term (e.g., over 6 months) with short-term perivascular interventions? To address this question, we modified a rat vein-graft model to prolong IH progression. We then applied Pericelle, a nanoparticle/hydrogel hybrid system that we developed for perivascular delivery of rapamycin, an established IH-inhibitory drug. Surprisingly, despite short (∼3-month) drug release, Pericelle demonstrated IH suppression throughout 3, 6, and 9 months with IH reduced from 115.58 ± 27.89 to 40.34 ± 5.18 at 9 months (P < 0.05, n = 6 rats), as indicated by morphometric analysis. Live animal ultrasonography showed the same trend. Consistently, histone-3 lysine-27 trimethylation, an epigenetic mark associated with IH progression, was decreased at 6 months after Pericelle treatment. Moreover, Pericelle exhibited promising efficacy in mitigating IH in a porcine model of arteriovenous fistula that mimics dialysis access. These results suggest that Pericelle-mediated suppression of IH in rat vein-grafts extends much beyond drug release, offering potential solutions to longstanding translational challenges in reducing OVR failure.

Layered materials exhibit potential for thermoelectric applications, which are reliant on microstructural texture for high performance. In this work, we present layered crystal stacking hot deformation (LCSHD), which leverages anisotropic crystal structures to induce rapid texture formation, leading to high thermoelectric performance. Taking n-type bismuth telluride (Bi2Te3) as a representative, the LCSHD method contributed to a record-high power factor (PF) of 45 μW cm−1K−2in polycrystals. Additionally, the dislocation tangle and low-angle grain boundary can be found in the LCSHD sample, producing low lattice thermal conductivity and a remarkable ZTvalue of 1.2. Benefiting from a reliable high ZT, we prepared a seven-pair Bi2Te3-based module, which displayed an extraordinary conversion efficiency of 6.4% and competitive refrigeration performance. In addition, a significant improvement of ZTvalue in other layered materials, including SnSe2and SnSe, was also demonstrated. Our finding offers novel avenues for texture engineering, facilitating the design of high-performance layered thermoelectric materials.

This study investigates how extracellular polymeric substances (EPS) synthesized by dark septate endophytic (DSE) improve alfalfa’s drought resistance. Drought stress was simulated in hydroponic culture, and roots were treated with different EPS concentrations to determine their effects on drought tolerance and applicable concentrations. Hydroponic solutions with 0.25 and 0.50% EPS concentrations alleviated leaf wilting and increased total plant fresh weight by 35.8 and 57.7%, respectively. SEM shows that EPS attached to the roots and may have served to protect the root system. EPS treatment significantly depressed the MDA contents of the roots, stems, and leaves. Roots responded to drought stress by increasing soluble sugar contents and antioxidant enzyme activities, while mitigating stem and leaf stress by synthesizing lipid compounds, amino acids, and organic acid metabolites. Five metabolites in the stem have been reported to be associated with plant stress tolerance and growth, namely 3-O-methyl 5-O-(2-methyl propyl) (4S)-2,6-dimethyl-4-(2-nitrophenyl)-3,4-dihydropyridine-3,5-dicarboxylate, malic acid, PA (20:1(11Z)/15:0), N-methyl-4,6,7-trihydroxy-1,2,3,4-tetrahydroisoquinoline, and 2-(S-glutathionyl) acetyl glutathione. In summary, EPS treatment induced oxidative stress and altered plant metabolism, and this in turn increased plant antioxidant capacity. The results provide a theoretical basis for the application of EPS in commercial products that increase plant resistance and ecological restoration.

The effects of Ag content on the microstructure and shear strength of Sn−xAg−0.5Cu solder joints under rapid thermal shock were investigated using high-frequency induction heating equipment. The results show that the increased Ag content can make the surface of the solder joint denser and smoother and reduce the generation of long strips of Cu6Sn5intermetallic compound (IMC) inside the solder joint, thus enhancing the oxidation resistance of the solder joint. Ag accelerates the growth rate of the IMC layer at the solder joint interface, the growth rate of the Cu6Sn5layer is determined by both bulk diffusion and grain boundary diffusion, and the growth rate of the Cu3Sn layer is determined by both bulk diffusion and interfacial reaction. In the rapid thermal shock environment, the fracture mode of the solder joint converts from ductile fracture to brittle fracture. At the same time, the high Ag content shortens the fracture mode transition time of the solder joint and reduces the thermal fatigue resistance of the solder joint.

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High-temperature treatment is key to the preparation of zeolite catalysts. Herein, the effects of high-temperature treatment on the property and performance of HZSM-5 zeolites were studied in this work. X-Ray diffraction, N2physisorption, 27Al magic angle spinning nuclear magnetic resonance (MAS NMR), and temperature-programmed desorption of ammonia results indicated that the high-temperature treatment at 650 °C hardly affected the inherent crystal and texture of HZSM-5 zeolites but facilitated the conversion of framework Al to extra-framework Al, reducing the acid site and enhancing the acid strength. Moreover, the high-temperature treatment improved the performance of HZSM-5 zeolites in n-heptane catalytic cracking, promoting the conversion and light olefins yield while inhibiting coke formation. Based on the kinetic and mechanism analysis, the improvement of HZSM-5 performance caused by high-temperature treatment has been attributed to the formation of extra-framework Al, which enhanced the acid strength, facilitated the bimolecular reaction, and promoted the entropy change to overcome a higher energy barrier in n-heptane catalytic cracking.

Background and objective: The effectiveness and long-term efficacy of edaravone, a recommended treatment for amyotrophic lateral sclerosis (ALS), has not been examined in real-world settings. This study aims to evaluate the effectiveness and long-term efficacy of edaravone. Methods: The OVID Medline, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched for articles published between January 1, 2000, and May 1, 2023. Two investigators independently screened the retrieved articles for randomized controlled trials (RCTs), cohort studies, or single-arm trials that evaluated the effect of edaravone on amyotrophic lateral sclerosis (ALS). The risk of bias was evaluated using the revised Cochrane Risk-of-Bias (RoB 2.0) tool for randomized controlled trials (RCTs) and the Risk-of-Bias In Non-randomized Studies of Interventions (ROBINS-I) tool for observational studies. The primary outcome was the ALSFRS-R score assessed at month 6, with secondary outcomes including the ALSFRS-R scores evaluated at months 9, 12, and 18, forced vital capacity (FVC), and adverse events. The certainty of evidence was assessed using the GRADE approach. Results: The analysis included 16 studies with a total of 4828 participants. Among these, four were randomized controlled trials (RCTs) and 12 were observational studies. Of the RCTs, four were rated as having a low risk of bias, while six of the observational studies were rated as having a low risk of bias. Edaravone was associated with slightly slower progression in the reduction of ALSFRS-R score at month 6 compared to placebo (mean difference 1.01, 95%CI −0.87 to 3.09, p= 0.293), as shown by evidence from RCTs. However, observational studies did not show any benefit of adding edaravone to routine practice (mean difference 1.85, 95%CI −2.05 to 5.75, p= 0.352). The change from baseline in ALSFRS-R score was −2.1, −4.04, −7.5, −6.82, and −7.9 at months 3, 6, 9, 12, and 18, respectively. The GRADE assessment indicated moderate certainty for evidence from RCTs, while evidence from observational studies had very low certainty. Conclusion: Due to the limited number of studies and confounding issues in observational studies, further examination of the added benefits of edaravone to routine practice is necessary through RCTs, particularly regarding its long-term efficacy.

Rule-based fuzzy models have modular architectures and come with well-developed design methodologies such that they can build accurate models with good interpretabilities in system modeling. However, a large amount of private data needs to be used for statistical analysis and forecasting in rule-based fuzzy models. The purpose of this study is to build an intelligent model with high accuracy and versatility under the premise of data privacy and model security. To mitigate the risk of malicious attacks on privacy data during the analysis process, we have employed highly regarded differential privacy techniques to devise a novel rule-based fuzzy modeling approach. We propose a function approximation mechanism to reconstruct the objective function and add a perturbation mechanism to the objective function in the Takagi–Sugeno rules model. Taking into account the delicate balance between data privacy and utility, we have innovatively introduced a Takagi–Sugeno rule-based model based on differential privacy. This model is applicable to both linear and nonlinear systems, offering protection to sensitive data privacy and model security within the system. We investigate the relationship between the interpretability of the model and the degree of privacy protection. By constructing a reasonable rule base, we achieve higher accuracy than other system modeling methods based on differential privacy. This article compares the influence of the number of rules on differential privacy and considers the algorithm performance under various noise distributions. It is shown that the Takagi–Sugeno rules model based on differential privacy has a strong ability to predict and analyze data.

Effective prevention of traps in financial networks has become a focus of attention. Faced with the diversity of financial data and the complexity of financial traps, how to measure the risk value of investment behavior is very important. After analyzing the nature of risk, this paper puts forward an analysis of the characteristics of Pompeii trap in American finance based on human autonomous equipment. The feature analysis method based on human autonomous equipment is one of many risk measurement methods. On this basis, the information entropy risk function is established, and the validity of the model can be proved by experiments. The experimental results show that the model can help users avoid the so-called risk-free, high-yield, virtual investment projects, and avoid falling into the financial Ponzi scheme of borrowing new and repaying old.

In this paper, a novel multiscale morphological filter, called multiscale enhanced cascaded difference filter (MECDF), is proposed for the fault detection of road heading bearings. Firstly, the cascaded morphological operators are established based on the cascade of the basic morphological operators with similar properties, and then the morphological difference operation is introduced to propose the cascaded difference operators. Subsequently, the enhanced cascaded difference operator (ECDO) is constructed through the convolution of cascaded difference operators. Moreover, since the scale range of structure element (SE) also determines the filtering performance of multiscale morphological filter, an improved multiscale analysis method is presented to select the optimal scale range. Finally, the bearing experimental signals are implemented to validate the effectiveness of MECDF. Experimental results testify that the scale range determined by the MECDF is better than other multiscale morphological filters. Meanwhile, the feature extraction capability of ECDO is also better than other existing morphological difference operators.

Temperature gradient generated by a huge current load is an adverse situation that insulation components of high-voltage (HV) apparatuses have to withstand. It could induce thermal stress, mechanical crack or even dielectric breakdown in epoxy-based insulation. In this article, micrometer-sized hexagonal boron nitride ( ${h}$ -BN) particles with high thermal conductivity were doped into the epoxy/Al2O3 composite to regulate its thermodynamics and further improve the insulation performance under a temperature gradient. The dielectric properties, ac breakdown strength, and electrical treeing degradation were studied with varying volume ratios of Al2O3 and BN. Results show that when the volume ratio of Al2O3 and BN reaches 6:4, the thermal conductivity increases to 1.68 W/( $\text {m}\cdot \text { K}$ ). The introduction of BN particles improves the ac breakdown strength and electrical tree breakdown time of epoxy/Al2O3 composite. The effects of BN doping were analyzed by phase field simulation, and results show that the epoxy/Al2O3/BN compounds are able to increase the number of discharge channels, improve the thermal diffusion efficiency, and reduce the internal stresses, thus enhancing the insulation performance of the epoxy composites.

ABSTRACTMany low-income and minority-concentrated neighborhoods have been struggling for decades with the acute problem of endemic abandonment in shrinking cities. Using high-resolution spatial–temporal data, this study attempts to extend our understanding of the influence of abandonment on future abandonment and the impact of interventions such as demolition by identifying spatial patterns of housing abandonment and demolition in Buffalo, New York when the city invested heavily in an aggressive 5-in-5 demolition plan targeting predominantly African American neighborhoods with high rates of abandonment. Our results confirmed that the clustering of abandoned properties has been consistently confined to the city's majority African American east side neighborhood. We found a higher level of duress housing sales on the east side after the 5-in-5 plan's implementation. In essence, 5-in-5 was a demolition and slum clearance policy akin to mid-twentieth-century urban renewal programs focusing on removing blighted properties without a concomitant revitalization component.

To enhance the stability of the polymeric micelles and optimize their drug-controlled release ability, three disulfide-linked polyethylene glycol methyl ether methacrylate–disulfide–poly(ε-caprolactone-co-γ-amine−ε-caprolactone) (PPEGMA-SS-P(CL-co-ACL)) polymers were synthesized and characterized by 1H NMR, GPC, and FT-IR successfully, and their dual pH/reduction-responsive cross-linked polymeric micelles were prepared for paclitaxel (PTX) delivery by using 2,3-dimethylmaleic anhydride (DMMA) as the cross-linking agent. The PTX loading capacity (LC) and encapsulation efficiency (EE) values of the cross-linked micelles formed by PPEGMA8-SS-P(CL47-co-ACL15) achieved were 23.96% and 71.58%, slightly higher than those of un-cross-linked micelles. Both particle sizes of blank micelles and in vitrodrug release of PTX-loaded micelles confirmed that compared with those un-cross-linked micelles, the cross-linked micelles were more stable at pH 7.4 + 0 mM DTT, with a PTX cumulative release of 13% at 120 h, while the PTX cumulative release of the cross-linked micelles at pH 5.0 + 10 mM DTT were close to that of un-cross-linked micelles after 60 h, indicating the successful reversible cross-linking and smooth drug release of the cross-linked micelles. The cytotoxicity assay showed that PPEGMA8-SS-P(CL47-co-ACL15) and its cross-linked micelles had low cell cytotoxicity, and both PTX-loaded micelles revealed a certain inhibitory effect on HepG2 cells. These results revealed that the dual pH/reduction-responsive cross-linked polymeric micelles prepared from PPEGMA8-SS-P(CL47-co-DCL15) were a promising candidate for PTX delivery.

Oxidation behavior of SAC305/Cu solder joints and kinetics of intermetallic compound (IMC) growth were investigated using an electromagnetic induction heating device. The results show that the solder joint undergoes oxidation when subjected to rapid thermal shock. The oxidation behavior of the solder joint itself is the main factor, which is exacerbated by the presence of the internal Cu6Sn5IMC. The growth of the Cu6Sn5layer is controlled by grain boundary diffusion, while that of the Cu3Sn layer is controlled by bulk diffusion. The dissolved Cu of the substrate diffuses mainly into the interfacial IMC and the interior of the solder. Under rapid thermal shock, the shear strength of the solder joint decreases substantially, by 49.2% after 72 h. The fracture mechanism changes from ductile fracture to mixed tough−brittle fracture and finally, to brittle fracture.

Various aggregation-induced emission luminogens (AIEgens) have been developed and applied in different areas in recent years. However, AIEgens generally can aggregate and emit strong fluorescence in aqueous solution even containing DNA and other biomacromolecules because of poor water solubility, restricting their application in biosensing and bioimaging in aqueous solution. Moreover, the great majority of AIEgens commonly suffer from complex organic synthesis, environmental damage, and biological toxicity. In this work, jatrorrhizine (Jat), an isoquinoline alkaloid from Chinese herbs, was found to be a natural water-soluble AIEgen that has not been previously reported. Jat’s photometric characteristics and single-crystal structure demonstrated that the restriction of intramolecular motion and twisted intramolecular charge transfer were responsible for its AIE phenomenon. Due to the good water solubility and AIE character of Jat, it did not emit fluorescence in the aqueous solution containing DNA and polymers until the formation of the DNA hydrogel. Therefore, a DNA hydrogel fluorescence biosensor was designed by using the target (miRNA) as a catalyst to trigger the entropy-driven circuit of DNA, realizing the ultrasensitive and label-free detection of miRNA with an ultralow limit of detection (0.049 fM, S/N = 3). This biosensing strategy also has excellent stability and acceptable reliability for real sample assay. The results not only indicated the excellent sensing performance of Jat as AIE probes in aqueous solution but also demonstrated the promising application potential of water-soluble natural AIEgens.

Colorectal cancer (CRC) is one of the most common cancers and supplementation of probiotics may be a promising intervention method. The present study aimed to investigate the anti-CRC effects of Lactiplantibacillus plantarumKX041 on a CRC mouse model. The CRC mice were induced by 10 mg/kg azoxymethane and 2 % dextran sulfate sodium. L. plantarumKX041 was orally administrated once daily (1 × 109CFU/mouse). Results showed that L. plantarumKX041 could significantly inhibit inflammation, tumor formation, and induce tumor cells apoptosis. Moreover, this probiotic could ameliorate the damage of intestinal barrier by recovering tight junction protein expression (like Occludin, Claudin-1, and ZO-1) and preventing goblet cell loss. Furthermore, the oxidative stress was alleviated by increasing the level of antioxidant mediators (like GSH and SOD) and reducing the level of oxidative mediators (like MDA and MPO). In addition, treatment with L. plantarumKX041 could directly regulate gut microbiota, thereby increasing the abundance of beneficial bacteria (like SCFAs-producing bacteria, Akkermansia) and decreasing the abundance of harmful bacteria (like pro-inflammatory bacteria, Parasutterella), which in turn raised SCFAs levels and lowered LPS levels. In conclusion, L. plantarumKX041 could effectively ameliorate CRC via reshaping intestinal microenvironment, alleviating inflammation, maintaining intestinal permeability, and attenuating oxidative stress.

Manipulating active sites of catalysts is crucial but challenging in catalysis science and engineering. Beyond the design of the composition and structure of catalysts, the confined electromagnetic field in optical cavities has recently become a promising method for catalyzing chemical reactions via strong light–matter interactions. Another form of confined electromagnetic field, the charge density wave in plasmonic cavities, however, still needs to be explored for catalysis. Here, we present an unprecedented catalytic mode based on plasmonic cavities, called plasmonic cavity-catalysis. We achieve direct control of catalytic sites in plasmonic cavities through standing hot carrier waves. Periodic catalytic hotspots are formed because of localized energy and carrier distribution and can be well tuned by cavity geometry, charge density, and excitation angle. We also found that the catalytic activity of the cavity mode increases several orders of magnitude compared with conventional plasmonic catalysis. We ultimately demonstrate that the locally concentrated long-lived hot carriers in the standing wave mode underlie the formation of the catalytic hotspots. Plasmonic cavity-catalysis provides a new approach to manipulate the catalytic sites and rates and may expand the frontier of heterogeneous catalysis.

Single-atom nanozymes (SAzymes) are novel mimic-enzyme materials with atomically doped active sites. They play a pivotal role in the field of nanozymes because of their excellent catalytic activities, high utilization efficiency of the metal atoms, and simple model of active sites. Herein, the peroxidase (POD)-like SAzymes with high-loading iridium (Ir) (5.31%) on graphene oxide (GO) nanosheets [Ir(III)/GO] were prepared through a coordination reaction between the Ir(III) complex and the oxygen-containing groups in GO. The preparation strategy avoids nitrogen doping and pyrolysis procedures which are the usually used strategies to improve the GO-based enzyme mimic activity. Ascribed to the highly active Ir atoms, Ir(III)/GO SAzymes demonstrate outstanding POD-like activity without the oxidase-like activity. In advantage of the excellent POD-like activity, a simple and sensitive colorimetric pesticide detection platform is established. The developed sensing platform offers an excellent “switch-on” pirimicarb (PIB) detection in the linear range of 10–300 nM with a limit of detection (LOD) of 2.81 nM. Moreover, the detection platform was fabricated into a portable test kit, which is composed of a test swab and sample processing tube. In the aid of a color-reading APP, the test kit can detect PIB with the LOD of 3.31 nM. It is astonishing to get this excellent detection sensitivity just using the simple colorimetric strategy. This work not only provides a novel strategy to synthesize Ir-based SAzymes but also exhibits the super capability of Ir(III)/GO in the biosensing field.

Selective inhibitors targeting the first bromodomain (BD1) or the second bromodomain (BD2) of the bromodomain and extra terminal domain (BET) proteins have triggered extensive research to produce more specific agents. Herein, we described our efforts to design and synthesize a series of selective BET BD2 inhibitors with novel structures. Among them, compound 45showed single-digit nanomolar potency against BRD4 BD2 (IC50: 1.6 nM) and a 328-fold selectivity for BRD4 BD2 over BRD4 BD1 (IC50: 524 nM). Besides, 45possessed potent effects on regulating the differentiation of Th17 cells and reducing the levels of Th17-related cytokines by affecting the activation of STAT3 and NF-κB. Further studies demonstrated that 45had significant therapeutic efficacy in mouse models of imiquimod (IMQ)-induced psoriasis and dextran sulfate sodium (DSS)-induced inflammatory bowel disease (IBD). This work provides a strong foundation for the development of selective BET BD2 inhibitors and the therapeutic strategy for psoriasis and IBD.

Abdominal aortic aneurysm (AAA) is a progressive aortic dilatation, causing ∼80% mortality upon rupture. Currently, there is no approved drug therapy for AAA. Surgical repairs are invasive and risky and thus not recommended to patients with small AAAs which, however, account for ∼90% of the newly diagnosed cases. It is therefore a compelling unmet clinical need to discover effective non-invasive strategies to prevent or slow down AAA progression. We contend that the first AAA drug therapy will only arise through discoveries of both effective drug targets and innovative delivery methods. There is substantial evidence that degenerative smooth muscle cells (SMCs) orchestrate AAA pathogenesis and progression. In this study, we made an exciting finding that PERK, the endoplasmic reticulum (ER) stress Protein Kinase R-like ER Kinase, is a potent driver of SMC degeneration and hence a potential therapeutic target. Indeed, local knockdown of PERK in elastase-challenged aorta significantly attenuated AAA lesions in vivo. In parallel, we also conceived a biomimetic nanocluster (NC) design uniquely tailored to AAA-targeting drug delivery. This NC demonstrated excellent AAA homing via a platelet-derived biomembrane coating; and when loaded with a selective PERK inhibitor (PERKi, GSK2656157), the NC therapy conferred remarkable benefits in both preventing aneurysm development and halting the progression of pre-existing aneurysmal lesions in two distinct rodent models of AAA. In summary, our current study not only establishes a new intervention target for mitigating SMC degeneration and aneurysmal pathogenesis, but also provides a powerful tool to facilitate the development of effective drug therapy of AAA.

Point defects play a critical role in the transport properties of Mg3Sb2-based thermoelectric materials. However, the determination of point defects is rather challenging. Herein, Mg3Sb2single crystals were prepared by the self-flux method with the Sb flux (p-type sample) and Mg flux (n-type sample). The crystal structure as well as the atomic occupancy parameters of these samples were determined by single-crystal and synchrotron powder X-ray diffractions. Comparison between the experimental and calculated Fourier electron density maps generated by single-crystal data indicates the existence of Mg interstitials [1/3, 2/3, 0.38(3)] and vacancies at the Mg2 sites [2/3, 1/3, 0.8653(3)] in the n-type sample and Mg vacancies at both the Mg1 and Mg2 sites in the p-type sample. In addition, differences in the peak positions and intensities of the two types of Mg–Sb vibration modes in Raman spectra were observed between different Mg3Sb2crystals, which suggests that point defects can impact the vibration modes.

• The mechanical properties of different kinds of thermoelectric generators (TEGs) and their optimization are reviewed. • The mechanical properties of thermoelectric materials affect the mechanical properties of TEGs. • The strength of joints between thermoelectric material and electrode affects the mechanical properties of TEGs. • Flexible substrates with excellent mechanical performance help to share the stress generated by the bending of flexible thermoelectric materials. To satisfy the requirements of practical applications, thermoelectric generators should be highly efficient and mechanically robust. Recently, progress in designing high-performance thermoelectric generators has been made. However, the mechanical properties of thermoelectric generators are still unsatisfactory. In this review, studies on the mechanical properties of thermoelectric generators are summarized. The mechanical properties of bulk thermoelectric generators will be first discussed. In this section, the mechanical properties of thermoelectric materials and the strategies for improving their mechanical properties are emphasized. Since the device's failure usually occurs at the interface between the thermoelectric materials and electrode, the joint strength of electrodes and thermoelectric materials will be overviewed. After that, the mechanical properties of the inorganic thin-film thermoelectric devices will be discussed. Since the figure of merit for the flexibility of thermoelectric materials depends on the film thickness, elastic modulus, and yield strength, the synthesis methods of thin-film thermoelectric materials will be reviewed. Finally, this review will be concluded with a discussion on flexible organic thermoelectric devices and flexible devices using bulk legs. [ABSTRACT FROM AUTHOR]

ABSTRACTOnshore shale oil is difficult to develop due to its special pore structure and low permeability characteristics. Artificial fracturing causes a large amount of fracturing fluid to intrude into the reservoir, resulting in a complex reservoir seepage pattern. Therefore, this paper aims to explore the changes in the reservoir at the macro and micro levels due to the interaction between fracturing fluids and shale oil reservoirs. For this, four rock samples from shale oil reservoirs and two fracturing fluids commonly used in the mine were used. Then, core repulsion, scanning electron microscopy, X-ray diffraction and CT scanning experiments were carried out successively. The following results were derived from our analyses. (1) Permeability of the rock samples was reduced by an average of 24.47% after replacement by fracturing fluid, while the experimental groups with larger fluid-grain sizes and well-developed fracture networks suffered more significant solid-phase damage and fluid-phase trapping. (2) Fracturing fluids have different effects on fractures at different scales; large fractures (>7.71 μm) were widened, while small fractures (<3.47 μm) were shrunk or even plugged. (3) Based on the water-sensitive effect, fracturing fluids can disperse and transport clay minerals, resulting in fluid-phase damage and an average decrease of 14.33% in clay content in the reservoir. (4) Analysis of the digital core model shows that fracturing fluid intrusion and retention can cause solid-phase damage to the reservoir matrix, with 38.14% and 60% damage to the pore and throat channels, respectively. This paper uses a combination of physical experiments and numerical analysis to investigate the interaction mechanism between fracturing fluids and shale oil reservoirs from both microscopic and macroscopic perspectives. Overall, the results of this study provide experimental support for future studies on the seepage characteristics of this type of reservoir and the design of fracturing construction schemes.

• n-Type CdSb is realized through indium doping. • The valley degeneracy is as large as ten for the conduction band in CdSb. • Band modeling suggests that the thermoelectric figure of merit could reach ∼1.2 at 450 K under the optimal electron concentration. Realizing high performance in both n-type and p-type materials is essential for designing efficient thermoelectric devices. However, the doping bottleneck is often encountered, i.e., only one type of conduction can be realized. As one example, p-type CdSb with high thermoelectric performance has been discovered for several decades, while its n-type counterpart has rarely been reported. In this work, the calculated band structure of CdSb demonstrates that the valley degeneracy is as large as ten for the conduction band, and it is only two for the valence band. Therefore, the n-type CdSb can potentially realize an exceptional thermoelectric performance. Experimentally, the n-type conduction has been successfully realized by tuning the stoichiometry of CdSb. By further doping indium at the Cd site, an improved room-temperature electron concentration has been achieved. Band modeling predicts an optimal electron concentration of ∼2.0 × 1019 cm−3, which is higher than the current experimental values. Therefore, future optimization of the n-type CdSb should mainly focus on identifying practical approaches to optimize the electron concentration. [Display omitted] [ABSTRACT FROM AUTHOR]

• n-Type SnSe is realized through rare earth element Ce doping. • PbTe alloying further increases the power factor and decreases the thermal conductivity. • A high average zT value of ∼0.52 between 300 and 823 K is achieved in Sn 0.9 Pb 0.07 Ce 0.03 Se 0.93 Te 0.07. SnSe exhibits excellent thermoelectric performance in both n- and p-type single crystals, but its n-type polycrystals are restricted because of the lower electrical conductivity. Here, we dually introduced rare earth element Ce and PbTe to optimize the thermoelectric properties of n-type SnSe polycrystals. It is demonstrated that Ce is an effective cationic dopant to convert SnSe from p- to n-type conductor, and an enhanced peak zT value of ∼0.9 at 823 K was obtained in Sn 0.97 Ce 0.03 Se due to the improved power factor. Furthermore, PbTe alloying not only reduced the band gap to increase the carrier concentration, but also enhanced the density-of-states effective mass, and hence further increased the power factor in the whole measured temperature range. Meanwhile, the lattice thermal conductivity was significantly reduced owing to the enhanced phonon scattering by the mass and strain fluctuations. As a result, the peak zT value was increased to ∼1.3 for Sn 0.9 Pb 0.07 Ce 0.03 Se 0.93 Te 0.07 together with a high average zT value of ∼0.52 in the temperature range of 300 to 823 K. [ABSTRACT FROM AUTHOR]

Understanding and managing hot electrons in metals are of fundamental and practical interest in plasmonic studies and applications. A major challenge for the development of hot electron devices requires the efficient and controllable generation of long-lived hot electrons so that they can be harnessed effectively before relaxation. Here, we report the ultrafast spatiotemporal evolution of hot electrons in plasmonic resonators. Using femtosecond-resolution interferometric imaging, we show the unique periodic distributions of hot electrons due to standing plasmonic waves. In particular, this distribution can be flexibly tuned by the size, shape, and dimension of the resonator. We also demonstrate that the hot electron lifetimes are substantially prolonged at hot spots. This appealing effect is interpreted as a result of the locally concentrated energy density at the antinodes in standing hot electron waves. These results could be useful to control the distributions and lifetimes of hot electrons in plasmonic devices for targeted optoelectronic applications.

Yield loss due to low precipitation use efficiency (PUE) occurs frequently in dryland crop production. PUE is determined by a complicated process of precipitation use in farmland, which includes several sequential steps: precipitation infiltrates into the soil, the infiltrated precipitation is stored in soil, the soil-stored precipitation is consumed through transpiration or evaporation, transpired precipitation is used to produce dry-matter, and finally dry-matter is re-allocated to grains. These steps can be quantified by six ratios: precipitation infiltration ratio (SW/SWe; SW, total available water; SWe, available soil water storage at the end of a specific period), precipitation storage ratio (SWe/P; P, effective precipitation), precipitation consumption ratio (ET/SW; ET, evapotranspiration), ratio of crop transpiration to evapotranspiration (T/ET; T, crop transpiration), transpiration efficiency (B/T; B, the increment of shoot biomass) and harvest index (Y/B; Y, grain yield). The final efficiency is then calculated as: PUE=SWeP×SWSWe×ETSW×TET×BT×YB. Quantifying each of those ratios is crucial for the planning and execution of PUE improvements and for optimizing the corresponding agronomic practices in a specific agricultural system. In this study, those ratios were quantified and evaluated under four integrated agronomic management systems. Our study revealed that PUE and wheat yield were significantly increased by 8–31% under manure (MIS) or biochar (BIS) integrated systems compared to either conventional farmers’ (CF) or high N (HN) integrated systems. In the infiltration and storage steps, MIS and BIS resulted in lower SWe/P but higher SW/SWe compared with CF and HN. Regarding the consumption step, the annual ET/SW under MIS and BIS did not increase due to the higher ET after regreening and the lower ET before regreening compared with CF or HN. The T/ET was significantly higher under MIS and BIS than under CF or HN. In the last two steps, transpiration efficiency and harvest index were less strongly affected by the agronomic management system, although both values varied considerably across the different experimental years. Therefore, attempts to achieve higher PUE and yields in rainfed wheat through agronomic management should focus on increasing the T/ET and SW/SWe, while maintaining ET/SW throughout the year and keeping SWe/P relatively low at harvest time.

Graphical Abstract:

This paper addresses the fault diagnosis problem of PLC-based systems that can be modeled as Petri nets under a certain level of abstraction. The existing Petri-net-based fault diagnosis approaches often associate transitions and/or places with sensors and require that any change in sensor readings needs to be treated by a PLC, leading to a situation that the PLC would be too busy processing the changes in sensor readings to perform other tasks. This paper assumes that a PLC does not monitor the changes of readings of sensors all the time, but periodically reads the values of sensors when needed. The system output is defined as a marking sequence interleaved with possible observed transitions. A fault diagnosis algorithm is developed by defining and solving integer linear programing (ILP) problems whose size is regardless of the length of the system output. The proposed approach enjoys high computational efficiency compared with other ILP-based approaches and is more suitable for fault diagnosis of PLC-based systems with low computing power.

• Resource automaton and probabilistic resource automaton models are constructed. • A new method to quantify the opacity of a system is proposed from a gaming perspective. • A game current-state analyzer is constructed to verify the game-current state opacity. • The problem of verifying the game current-state opacity is decidable. We investigate the quantitative current-state opacity problem with resource constraints in the framework of probabilistic resource automata which is partially observed. Resource information states and event payoffs capture the variations of a resource that can be consumed or replenished during a system evolution. There are a number of ways to quantify opacity in discrete event systems, but these quantification methods have certain limitations. This research mitigates this restriction by extending current-state opacity and step-based almost current-state opacity formulations to probabilistic resource automata under partial observation with payoff constraints. We define game current-state opacity with an aim of offering a quantitative measure for opacity. We also construct a game current-state analyzer for the verification of game current-state opacity and prove the decidability of verifying the game current-state opacity problem. [ABSTRACT FROM AUTHOR]

Although the artificial Z-scheme system, mimicking natural photosynthesis, has shown promising applications in photocatalytic water splitting, it often suffers from the side reaction of redox mediator, which considerably undermines the efficacy of photocarrier utilizations. Herein, we propose to suppress the side reaction by using ferroelectric polarization, which not only provides a strong driving force to spatially separate photocarriers to the oppositely poled surface but also induces spatially selective adsorption of redox ions. Single-domain ferroelectric PbTiO3nanoplates have been adopted as a model ferroelectric to construct the Z-scheme system with BiVO4particles and a cationic redox mediator. In contrast to the inactive multi-domain ferroelectric PbTiO3-based system, the so-formed Z-scheme system delivers stable high activity for photocatalytic overall water splitting under both visible light and simulated solar insolation. This work offers a proof of concept to realize efficient solar photocatalytic water splitting based on single-domain ferroelectric Z-scheme system.

AbstractIn this paper, we present several sharp bounds for the reciprocals of the Neuman-Sándor mean in terms of the harmonic, arithmetic, quadratic, and contraharmonic means by using classical analysis and inequalities theory. Finally, we give a remark based on the generalized trigonometric and generalized hyperbolic functions.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ipm.2006.03.021 Byline: Li-chun Yin (a)(b), Hildrun Kretschmer (a)(c), Robert A. Hanneman (d), Ze-yuan Liu (a)(b) Keywords: Social network analysis; Cooperation network; Topological structure; Scale-free Abstract: Co-authorship among scientists represents a prototype of a social network. By mapping the graph containing all relevant publications of members in an international collaboration network: COLLNET, we infer the structural mechanisms that govern the topology of this social system. The structure of the network affects the information available to individuals, and their opportunities to collaborate. The structure of the network also affects the overall flow of information, and the nature of the scientific community. We present a number of measures of both the macro- (whole-network) and micro- (actor-centered) structure of collaboration, and apply these to COLLNET. We find that this scientific community displays many aspects of a 'small-world,' and is somewhat vulnerable to disruption should major figures become inactive. We also find inequality in the roles played by individuals in the network. The inequalities, however, do not create a closed and isolated 'core' or elite. Author Affiliation: (a) WISE LAB, Dalian University of Technology, Dalian 116023, China (b) Institute of Science Studies and Management of Science and Technology, Dalian University of Technology, Dalian 116023, China (c) Department of Library and Information Science, Humboldt-University Berlin, Dorotheenstrasse 26, D-10099 Berlin, Germany (d) Department of Sociology, University of California - Riverside, USA Article History: Received 16 March 2006; Accepted 16 March 2006

The energy scenario in China is studied with emphasis on the oil, gas and coal sectors. Liberal foreign investments are welcomed to improve China's energy infrastructure. Gas has priority for developed by tapping the north-western basin. China has in place the legal infrastructure and institutions including a foreign investment regulatory regime, even as it approaches the WTO accession.

In non-high-risk individuals, risk-category-based atherosclerotic cardiovascular disease (ASCVD) screening strategies may be more cost-effective than one-size-fits-all approaches. However, current decisions are constrained by a lack of research evidence. We aimed to explore appropriate risk-category-based screening interval strategies for non-high-risk individuals in ASCVD primary prevention in the Chinese population.

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The most crucial initial step in the metallization process of electroplating is the local contact openings in dielectric layers. In this article, an ultraviolet picosecond laser (UV‐ps), is used to open the front and back dielectric layer of the precursor of n‐TOPCon solar cells. By changing the laser parameters and spot overlap rate, the surface morphology of laser etching under different conditions is obtained and characterized by optical microscope and scanning electron microscope. The results indicate that there are three separate laser shock zones in the dielectric layer under the action of Gaussian light spot, and the corresponding ablation mechanisms are proposed. The longitudinal distribution of B element is characterized by secondary ion mass spectrometry to explore the effect of laser on its pn junction. In addition, the electrical characterization of lifetime photoluminescence is measured and calibrated using WCT120, and this indicates that the majority of the amorphous silicon is recrystallized when applying a fast firing oven process, and this hence improve the minority carrier lifetime and implied open‐circuit voltage. The laser damage to the emitter at the laser‐ablated regions is investigated using the emitter saturation current density, J0laserextracted by WCT120. Compared with the original profile, the profile of the emitter in the laser contact area does not change significantly, and the minimum damage can be achieved by optimizing the laser conditions. After laser ablation, the crystallinity of silicon in the heat‐affected zone on both sides of the groove area changes. After fast firing oven, the heat‐affected zone disappears or is improved.

Retroreflectors that can accurately redirect the incident waves in free space back along their original channels provide unprecedented opportunities for light manipulation. However, to the best of our knowledge, they suffer from either the bulky size, narrow angular bandwidths, or time-consuming postprocessing, which essentially limits their further applications. Here, a scheme for designing ultrathin all-angle real-time retroreflectors based on hyperbolic plasmonic metasurfaces is proposed and experimentally demonstrated. The physical mechanism underlying the scheme is the orthogonality between the traveling waves in free space and the canalized spoof surface plasmon on the hyperbolic plasmonic metasurfaces, which guarantee their high-efficiency and all-angle mutual conversion. In this case, the strong confinement characteristic that benefited from the enhanced light–matter interaction enables us to route and retroreflect the canalized spoof surface plasmon with extremely thin structures. As proof of the scheme, a retroreflector prototype with a thickness approximately equal to the central wavelength is designed and fabricated. Further experimental investigation obtains a half-power field of view up to 53° and a maximum efficiency of 83.2%. This scheme can find promising applications in target detection, remote sensing, and diverse on-chip light control devices.

Accumulating evidence indicates that mitochondrial dysfunction and oxidative stress play a pivotal role in the initiation and progression of nonalcoholic fatty liver disease (NAFLD). In this study, we found that blueberry-derived exosomes-like nanoparticles (BELNs) could ameliorate oxidative stress in rotenone-induced HepG2 cells and high-fat diet (HFD)-fed C57BL/6 mice. Preincubation with BELNs decreased the level of reactive oxygen species (ROS), increased the mitochondrial membrane potential, and prevented cell apoptosis by inducing the expression of Bcl-2 and heme oxygenase-1 (HO-1) and decreasing the content of Bax in rotenone-treated HepG2 cells. We also found that preincubation with BELNs accelerated the translocation of Nrf2, an important transcription factor of antioxidative proteins, from the cytoplasm to the nucleus in rotenone-treated HepG2 cells. Moreover, administration of BELNs improved insulin resistance, ameliorated the dysfunction of hepatocytes, and regulated the expression of detoxifying/antioxidant genes by affecting the distribution of Nrf2 in the cytoplasm and nucleus of hepatocytes of HFD-fed mice. Furthermore, BELNs supplementation prevented the formation of vacuoles and attenuated the accumulation of lipid droplets by inhibiting the expression of fatty acid synthase (FAS) and acetyl-CoA carboxylase 1 (ACC1), the two key transcription factors for de novo lipogenesis in the liver of HFD-fed mice. These findings suggested that BELNs can be used for the treatment of NAFLD because of their antioxidative activity.

JEL J21 * O10 The economics literature generally considers income poverty to be the main cause of child labour. However, recent papers have cast doubt on this, showing evidence that [...]

The recently emerged SARS-CoV-2 Omicron variant encodes 37 amino acid substitutions in the spike protein, 15 of which are in the receptor-binding domain (RBD), thereby raising concerns about the effectiveness of available vaccines and antibody-based therapeutics. Here we show that the Omicron RBD binds to human ACE2 with enhanced affinity, relative to the Wuhan-Hu-1 RBD, and binds to mouse ACE2. Marked reductions in neutralizing activity were observed against Omicron compared to the ancestral pseudovirus in plasma from convalescent individuals and from individuals who had been vaccinated against SARS-CoV-2, but this loss was less pronounced after a third dose of vaccine. Most monoclonal antibodies that are directed against the receptor-binding motif lost in vitro neutralizing activity against Omicron, with only 3 out of 29 monoclonal antibodies retaining unaltered potency, including the ACE2-mimicking S2K146 antibody1. Furthermore, a fraction of broadly neutralizing sarbecovirus monoclonal antibodies neutralized Omicron through recognition of antigenic sites outside the receptor-binding motif, including sotrovimab2, S2X2593and S2H974. The magnitude of Omicron-mediated immune evasion marks a major antigenic shift in SARS-CoV-2. Broadly neutralizing monoclonal antibodies that recognize RBD epitopes that are conserved among SARS-CoV-2 variants and other sarbecoviruses may prove key to controlling the ongoing pandemic and future zoonotic spillovers.

An efficient Ni-catalyzed hydrodifluoroalkylation of unactivated alkenes with bromodifluoroacetate by using PhSiH3as hydride source was developed. The transformation affords aliphatic difluorides with anti-Markovnikov regioselectivity. A wide range of highly remote alkenes, simple alkenes, drug molecules, commercially available CF2precursors, and even nonfluorinated substrates are competent in this reaction under mild conditions, demonstrating the practicability of the strategy. Moreover, mechanistic studies indicated that the difluoroalkyl radical might be a key intermediate to this transformation.

The reaction mechanisms of CO oxidative coupling to dimethyl oxalate (DMO) on different β-Mo2C(001) based catalysts have been studied by the density functional theory (DFT) method. The activity and selectivity of DMO formation on Mo termination of β-Mo2C(001) are poor, and its C termination has no catalytic activity. After loading a Cu monolayer, the CuML/Mo2C(001)–Mo catalyst shows poor activity for the CO oxidative coupling reaction, but on CuML/Mo2C(001)–C, the CO oxidative coupling reaction can occur owing to the synergistic effect between the Cu monolayer and Mo2C(001), and it is expected to be a catalyst to replace precious metal Pd in DMO generation. Furthermore, the d-orbital state density of the Cu monolayer on CuML/Mo2C(001)–C is most similar to that of the Pd monolayer of Pd(111), which is the reason why CuML/Mo2C(001)–C has high activity and selectivity to DMO on the CO oxidative coupling reaction.