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Attitude tracking on the unit sphere of dimension 3 based on sliding mode is considered in this article. The tangent bundle of Lagrangian dynamics that describes the rotational motion of a rigid body is first equipped with the structure of a Lie group, then a sliding subgroup emerged on it is defined. Next, a sliding‐mode controller is designed for attitude tracking that relies on an intrinsic error defined on the Lie group. Almost global asymptotic stability of the closed loop is demonstrated using the Lyapunov analysis. Comparisons of the proposed geometric sliding mode controller designed on the nonlinear manifold with one designed in the Euclidean space showed that under the same working conditions the former is more energy efficient, more robust to measurement noises, and has a shorter and smoother transient response. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction (ECR) holds great potential to alleviate the greenhouse effect and our dependence on fossil fuels by integrating renewable energy for the electrosynthesis of high-value fuels from CO2. However, the high thermodynamic energy barrier, sluggish reaction kinetics, inadequate CO2 conversion rate, poor selectivity for the target product, and rapid electrocatalyst degradation severely limit its further industrial-scale application. Although numerous strategies have been proposed to enhance ECR performances from various perspectives, scattered studies fail to comprehensively elucidate the underlying effect-performance relationships toward ECR. Thus, this review presents a comparative summary and a deep discussion with respect to the effects strongly-correlated with ECR, including intrinsic effects of materials caused by various sizes, shapes, compositions, defects, interfaces, and ligands; structure-induced effects derived from diverse confinements, strains, and fields; electrolyte effects introduced by different solutes, solvents, cations, and anions; and environment effects induced by distinct ionomers, pressures, temperatures, gas impurities, and flow rates, with an emphasis on elaborating how these effects shape ECR electrocatalytic activities and selectivity and the underlying mechanisms. In addition, the challenges and prospects behind different effects resulting from various factors are suggested to inspire more attention towards high-throughput theoretical calculations and in situ/operando techniques to unlock the essence of enhanced ECR performance and realize its ultimate application. [ABSTRACT FROM AUTHOR]

ABSTRACT The phase‐shifted full‐bridge (PSFB) converter has been widely used in DC/DC converters due to its soft‐switching characteristics. However, it still has many drawbacks. In order to solve the shortcomings of the PSFB converter, such as limited soft‐switching range, high loss of duty cycle, and high oscillating voltage of the secondary rectifier, a PSFB converter based on parallel variable inductor and series blocking capacitor is proposed in this study. A wide range of soft switching, low rectifier oscillation voltage, and no duty cycle loss can be realized by the auxiliary current‐controlled variable inductor and reasonable blocking capacitor design. In this study, the mechanism of soft switching and suppression of oscillation is discussed and some of the designs are given. Finally, the experimental results of a 200 W/50 kHz prototype are constructed in the laboratory to verify the feasibility and effectiveness of the proposed converter. [ABSTRACT FROM AUTHOR]

To achieve a coating density meeting the solid oxide fuel cell (SOFC) electrolyte requirements of high gas tightness and ionic conductivity, in this study, a new interface healing densification process based on a liquid-phase sintering induction mechanism was conducted on plasma-sprayed 8 mol% Y 2 O 3 -stabilized ZrO 2 (8YSZ) coatings. Using Fe 2 O 3 and Bi 2 O 3 as healing additives, metallurgical healing of unbound interfaces was achieved by impregnating the additives into the gap interfaces, followed by liquid-phase sintering at 1200 and 1050 °C. After healing, the YSZ coating exhibited a dense bulk-like microstructure with a significant reduction in the gas leakage rate by two orders of magnitude, and the oxygen ion conductivity of the coating was significantly increased. The YSZ coating healed with the Fe 2 O 3 additive showed an oxygen ionic conductivity nearly one order of magnitude higher than that of the as-sprayed coating, reaching more than 80% of the value of the high-temperature-sintered YSZ bulk. • A new interface healing process based on liquid-phase sintering was conducted on APS YSZ coatings. • The interface-healed YSZ coating exhibited a dense bulk-like microstructure. • The gas leakage rate of the interface-healed YSZ coating decreased by two orders of magnitude. • Ionic conductivity of the interface-healed YSZ coating reached > 80% of the sintered bulk. • The cell assembled with interface-healed YSZ-Fe 2 O 3 electrolyte achieved MPD of 1.04 W/cm2 at 800 °C. [ABSTRACT FROM AUTHOR]

The development of novel metal–organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu‐CTU‐based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu‐CTU to Ag‐CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 μmol g−1 h−1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering. [ABSTRACT FROM AUTHOR]

The development of novel metal–organic frameworks (MOFs) as efficient photocatalysts for hydrogen peroxide production from water and oxygen is particularly interesting, yet remains a challenge. Herein, we have prepared four cyclic trinuclear units (CTUs) based MOFs, exhibiting good light absorption ability and suitable band gaps for photosynthesis of H2O2. However, Cu‐CTU‐based MOFs are not able to photocatalyzed the formation of H2O2, while the alteration of metal nodes from Cu‐CTU to Ag‐CTU dramatically enhances the photocatalytic performance for H2O2 production and the production rates can reach as high as 17476 μmol g−1 h−1 with an apparent quantum yield of 4.72 %, at 420 nm, which is much higher than most reported MOFs. The photocatalytic mechanism is comprehensively studied by combining the isotope labeling experiments and DFT calculation. This study provides new insights into the preparation of MOF photocatalysts with high activity for H2O2 production through molecular engineering. [ABSTRACT FROM AUTHOR]

Mosquito-borne diseases, such as malaria, dengue fever, and the Zika virus, pose significant global health challenges, affecting millions annually. Due to increasing insecticide resistance, there is a growing interest in natural alternatives for mosquito control. Lemongrass essential oil, derived from Cymbopogon citratus, has shown promising repellent and larvicidal properties against various mosquito species. In this study, we investigated the larvicidal effect of lemongrass oil and its major compounds on Anopheles sinensis, the primary malaria vector in China. GC–MS analysis identified the major compounds of lemongrass oil as (+)-citronellal (35.60%), geraniol (21.84%), and citronellol (13.88%). Lemongrass oil showed larvicidal activity against An. sinensis larvae, with an LC50 value of 119.20 ± 3.81 mg/L. Among the major components, citronellol had the lowest LC50 value of 42.76 ± 3.18 mg/L. Moreover, citronellol demonstrated inhibitory effects on acetylcholinesterase (AChE) activity in An. sinensis larvae, assessed by homogenizing larvae at different time points following treatment. Molecular docking studies further elucidated the interaction between citronellol and AChE, revealing the formation of hydrogen bonds and Pi-Sigma bonds. Aromatic amino acid residues such as Tyr71, Trp83, Tyr370, and Tyr374 played a pivotal role in these interactions. These findings may contribute to understanding lemongrass oil’s larvicidal activity against An. sinensis and the mechanisms underlying these effects. [ABSTRACT FROM AUTHOR]

Understanding the dynamics of δ13C and δ18O in modern resin is crucial for interpreting (sub)fossilized resin records and resin production dynamics. We measured the δ13C and δ18O offsets between resin acids and their precursor molecules in the top‐canopy twigs and breast‐height stems of mature Pinus sylvestris trees. We also investigated the physiological and environmental signals imprinted in resin δ13C and δ18O at an intra‐seasonal scale. Resin δ13C was c. 2‰ lower than sucrose δ13C, in both twigs and stems, likely due to the loss of 13C‐enriched C‐1 atoms of pyruvate during isoprene formation and kinetic isotope effects during diterpene synthesis. Resin δ18O was c. 20‰ higher than xylem water δ18O and c. 20‰ lower than δ18O of water‐soluble carbohydrates, possibly caused by discrimination against 18O during O2‐based diterpene oxidation and 35%–50% oxygen atom exchange with water. Resin δ13C and δ18O recorded a strong signal of soil water potential; however, their overall capacity to infer intraseasonal environmental changes was limited by their temporal, within‐tree and among‐tree variations. Future studies should validate the potential isotope fractionation mechanisms associated with resin synthesis and explore the use of resin δ13C and δ18O as a long‐term proxy for physiological and environmental changes. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) over perovskite oxides, upon undergoing a lattice oxygen oxidation mechanism, is strongly oxygen vacancy‐correlated as determined by the oxygen ion diffusivity. Despite substantial efforts having been devoted to tuning the oxygen vacancy concentration in perovskite oxides, the impact of the concomitant altering of oxygen vacancy ordering is often underestimated. In particular, the underlying mechanism of how the ordering and the concentration of oxygen vacancy affect the lattice OER, and how to well balance them still remain inadequately understood. Herein, a series of Sr1−xCaxCo0.5Fe0.5O3−δ with gradually increased oxygen vacancy concentration and ordering are synthesized. Theoretical calculations indicated that a higher oxygen vacancy concentration promoted the lattice oxygen migration, whereas a higher oxygen vacancy ordering impeded it. Particularly, Sr0.5Ca0.5Co0.5Fe0.5O3−δ with a relatively higher oxygen vacancy concentration and a lower ordering displayed the maximum oxygen diffusion rate and the optimal OER activity, affording a current density of 10 mA cm−2 at a quite low overpotential of 310.2 mV, together with a small Tafel slope of 55.87 mV dec−1. This study sheds light on the critical influence of oxygen vacancy configuration on the lattice OER, and paves a compromised avenue to screen and design advanced electrocatalysts for various electrochemical devices. [ABSTRACT FROM AUTHOR]

The three‐level Vienna rectifier is widely used in industrial applications, such as electric vehicle charging systems and telecommunication power systems. Discontinuous pulse width modulation (DPWM) is widely used in three‐level AC/DC converters due to its features of switching loss minimization. However, the problems of neutral‐point voltage ripple, current zero‐crossing distortion, and switching losses are mutually coupled for the Vienna rectifier. To address these issues, a hybrid carrier‐based discontinuous pulse width modulation (HCB‐DPWM) with reduced neutral‐point (NP) voltage ripple and current distortion is proposed. First, the π$$ \pi $$/6 clamping period of the conventional DPWM is divided into three‐type clamping intervals, which reduce NP voltage ripple with shortened clamping period. Then, the elimination of current distortion around the current zero‐crossing point and the switching loss reduction are investigated. The implementation of the proposed HCB‐DPWM is given in detail. Finally, the simulation and experimental results of the Vienna rectifier are presented to validate the performance that the proposed HCB‐DPWM can eliminate current zero‐crossing distortion and reduce neutral‐point voltage ripple with different modulation indices. [ABSTRACT FROM AUTHOR]

The electrocatalytic hydrogen production and supercapacitor technologies have positive impacts on the environment, promoting the production and utilization of clean and renewable energy sources, thus facilitating the reduction of greenhouse gas emissions. Among them, cobalt oxide (Co 3 O 4) has emerged as an ideal choice for electrode materials in these technologies due to its low toxicity, affordability, and significant theoretical capacity. Nevertheless, practical applications are restricted by its low conductivity and sluggish reaction kinetics. Addressing these challenges, this study introduces a pioneering approach: the synthesis of oxygen vacancy-modified Co 3 O 4 /Co/NC small-sized nanoflower composite, which combines the advantages of abundant oxygen vacancies, small size effects, and nitrogen-doped porous carbon. The optimized Co 3 O 4 /Co/NC small-sized nanoflower exhibits high porosity and excellent conductivity, providing numerous active sites and effectively enhancing the ion and electron transport rates. As a consequence, optimized Co 3 O 4 /Co/NC shows a low Tafel slope and overpotential, highlighting its potential for catalytic application. Moreover, as an electrode for supercapacitors, optimized Co 3 O 4 /Co/NC demonstrates excellent long-term stability, maintaining 94.7% of its capacitance even after 5000 charge-discharge cycles. Additionally, it showed a significant specific capacity of 251.4 mAh g−1 when tested at 1 A g−1. In addition to addressing the pressing challenges associated with traditional Co 3 O 4 electrodes, this work opens up exciting avenues for designing and fabricating transition metal oxide-based materials with unprecedented electrochemical performance. This research addresses performance issues with cobalt oxide as an electrode material for capacitors and green hydrogen generation. Innovative methods involving nitrogen doping and the introduction of oxygen vacancies were employed to produce Co 3 O 4 /Co/NC-2 nanosheets with high porosity and a large surface area. These enhancements facilitate faster electrolyte ion diffusion, provide more active sites, and improve electrical conductivity. Nitrogen doping enhances charge transfer rates, while oxygen vacancies offer additional catalytic sites. [Display omitted] • Nitrogen doping and oxygen vacancies enhance the conductivity and reaction rate of cobalt oxide. • Nanoflowers prepared using freeze-drying technology exhibit high porosity, facilitating the diffusion of electrolytes. • This material can be applied in the fields of green catalysis and energy storage. [ABSTRACT FROM AUTHOR]

Grid‐forming inverters play a vital role in connecting renewable energy sources to the grid, and maintaining stable output voltage is essential for system operation. However, traditional dual‐PI voltage–current loop control suffers from slow response and weak disturbance rejection, leading to suboptimal control performance of grid‐connected inverter output voltage. Moreover, employing traditional dual‐PI control in grid‐connected inverters results in low output impedance, making them prone to subsynchronous oscillations and instability under strong grid conditions. To address these challenges, this study introduces a novel dual‐loop control strategy based on linear active disturbance rejection control (LADRC), wherein voltage loop is regulated by LADRC while current loop employs PI control. Quantitative analysis and experimental findings demonstrate that compared with traditional dual‐PI voltage–current loop control, the LADRC‐based dual‐loop control strategy offers higher bandwidth and lower steady‐state error, thereby enhancing the tracking speed and precision of grid‐forming inverter output voltage. The LADRC‐based dual‐loop control strategy reduces output impedance in grid‐forming inverter systems, lowering THD of output voltage and improving harmonic suppression under nonlinear loads. Experimental results show its robustness against strong grid conditions compared with traditional dual‐PI control, ensuring stable output voltage. [ABSTRACT FROM AUTHOR]

With the changing times, obesity has become a characteristic epidemic in the context of the current era. Insulin resistance (IR) is most commonly caused by obesity, and IR is a common basis of the pathogenesis of many diseases such as cardiovascular disease, nonalcoholic fatty liver disease, and type 2 diabetes, which seriously threaten human life, as well as health. A major pathogenetic mechanism of obesity-associated IR has been found to be chronic low-grade inflammation in adipose tissue. Specialized pro-resolving mediators (SPMs) are novel lipid mediators that both function as "stop signals" for inflammatory reaction and promote inflammation to subside. In this article, we summarize the pathogenesis of obesity-associated IR and its treatments and outline the classification and biosynthesis of SPMs and their mechanisms and roles in the treatment of obesity-associated IR in order to explore the potential of SPMs for treating metabolic diseases linked with obesity-associated IR. [ABSTRACT FROM AUTHOR]

Previous research has examined the impact of various factors on the academic success of undergraduate students in English Medium Instruction (EMI) environments, with the aim of improving students’ academic outcomes. However, clarity regarding the necessity and sufficiency of these factors for EMI academic success remains elusive, limiting a comprehensive understanding of this phenomenon. This study used crisp-set Qualitative Comparative Analysis (csQCA) to analyse data from 16 empirical studies that investigated factors influencing the academic success of social science undergraduate students in EMI settings, using the EMI Academic Success (EMIAS) model. The findings revealed that English language proficiency emerged as a necessary and sufficient condition for EMI academic success, while students’ characteristics appeared to be a sufficient but not necessary condition. In addition, three causal configurations leading to EMI academic success were identified among four condition variables – English language proficiency, students’ characteristics, educational background, and English language support. This study contributes to a deeper understanding of the determinants of EMI academic success and highlights the importance of students’ English language proficiency and their characteristics in the context of EMI. [ABSTRACT FROM AUTHOR]

In theory, two extreme forms of substances exist: the pure form and the single-molecule mixture form. The latter contains a mixture of molecules with molecularly different structures. Inspired by the "chemical space" concept, in this paper, I report a study of the single-molecule mixture state that combines model construction and mathematical analysis, obtaining some interesting results. These results provide theoretical evidence that the single-molecule mixture state may indeed exist in realistic synthetic or natural polymer systems. [ABSTRACT FROM AUTHOR]

The CLLLC resonant converter is a promising technology for electric vehicles and microgrids due to its ability to operate bidirectionally. This article presents a design of a bidirectional CLLLC resonant converter that is applied in the vehicle‐to‐grid (V2G). The battery side of the converter uses a two‐channel parallel structure to enhance its efficiency and reliability. In contrast, the DC‐bus side uses a transformer series structure to obtain the benefits of passive current sharing on the secondary side and reduce the transformer turns ratio. By utilizing the proposed design method, the converter can achieve a wide input and output voltage range, high efficiency, and high power density. The article analyzes the working principle of the converter and explains the design process, which includes the transformer turns ratio, magnetizing inductance, and resonance parameters. Finally, an experimental prototype is produced to verify the theory's validity and the design's feasibility. The prototype has a DC‐bus side voltage of 660–860 V, a battery side voltage of 250–500 V, and a maximum power output of 30 kW. The peak efficiency of the prototype is 98.2%, and its power density can reach up to 8 kW/L. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) plays an essential role in people's daily lives, such as healthcare, home, traffic, industry, and so on. With the increase in IoT devices, there emerge many security issues of data loss, privacy leakage, and information temper in IoT network applications. Even with the development of quantum computing, most current information systems are weak to quantum attacks with traditional cryptographic algorithms. This paper first establishes a general security model for these IoT network applications, which comprises the blockchain and a post-quantum secure identity-based signature (PQ-IDS) scheme. This model divides these IoT networks into three layers: perceptual, network, and application, which can protect data security and user privacy in the whole data-sharing process. The proposed PQ-IDS scheme is based on lattice cryptography. Bimodal Gaussian distribution and the discrete Gaussian sample algorithm are applied to construct the fundamental difficulty problem of lattice assumption. This assumption can help resist the quantum attack for information exchange among IoT devices. Meanwhile, the signature mechanism with IoT devices' identity can guarantee non-repudiation of information signatures. Then, the security proof shows that the proposed PQ-IDS can obtain the security properties of unforgeability, non-repudiation, and non-transferability. The efficiency comparisons and performance evaluations show that the proposed PQ-IDS has good efficiency and practice in IoT network applications. [ABSTRACT FROM AUTHOR]

This paper proposes a new hybrid control strategy to solve the problem of bidirectional wide voltage range regulation in CLLC converters. On the (LLC) side (G2V direction), the SSSA control method is employed for voltage boost, combined with bus voltage and burst control to achieve wide voltage regulation. On the (C) side (V2G direction), the SSSA and full/half‐bridge mode switching control are used to achieve V2G direction wide voltage regulation. This hybrid control strategy also enables high conversion efficiency in both directions without the need for additional components to reduce the converter power density. This is particularly suitable for OBC applications with strict requirements for converter volume and weight. A detailed analysis with mathematical derivation, hybrid control strategy, and converter operation principles is introduced in this paper. The following subchapters supplement the converter voltage gain, soft switching implementation conditions, and design considerations. Finally, the feasibility of the proposed control strategy was verified through an experimental prototype with an input voltage ranging from 340 to 430 V to an output voltage ranging from 225 to 450 V and bidirectional rated power of 6.6/3.3 kW. This prototype achieved a maximum conversion efficiency of 97.7% in the G2V direction and 97.1% in the V2G direction. [ABSTRACT FROM AUTHOR]

Background: Obesity is closely associated with lipid accumulation, inflammation and intestinal microbiota dysbiosis. Short‐ and long‐chain type structured lipids (SLCTs) are kinds of low‐calorie structured lipids and demonstrate anti‐obesity and hypolipidemia bioactivity. The objective of this study is to investigate the potential effects of dietary supplementation of SLCTs rich in short‐chain fatty acids and polyunsaturated fatty acids on high‐fat‐diet‐induced obesity and gut microbiota modulation in C57BL/6J mice. Results: Results showed that SLCTs supplementation ameliorated body weight, dyslipidemia, liver lipid accumulation, liver injury and systemic inflammation in obese mice. As expected, immunohistochemical analysis showed that SLCTs significantly increased the expression of proliferator‐activated receptor alpha and decreased the expression of Toll‐like receptor 4 in liver tissue. Furthermore, SLCTs supplementation significantly downregulated the expression level of liver inflammation‐related genes while upregulating the expression level of liver lipid metabolism‐related genes. Additionally, SLCTs supplementation markedly enhanced the diversity of gut microbiota, reduced the Firmicutes/Bacteroidetes ratio and increased the diversity and richness of beneficial intestinal microorganisms, such as Bacteroides, Lactobacillus, Lachnospiraceae NK4A136 group, Alloprevotella and Ruminococcaceae UCG‐014. Conclusion: Our work suggested that SLCTs may have the potential to reduce obesity associated with a high‐fat diet by regulating liver metabolism, inflammation and gut microbiota. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Cancer antigen 125 (CA125) is a serum marker associated with ovarian cancer. Despite its widespread use, CA125 levels can also be elevated in benign conditions. Recent reports suggest that detecting serum CA125 that carries the Tn antigen, a truncated O -glycan containing only N -acetylgalactosamine on serine or threonine residues, can improve the specificity of ovarian cancer diagnosis. In this study, we engineered cells to express CA125 with a Tn antigen. To achieve this, we knocked out C1GALT1 and SLC35A1 , genes encoding Core1 synthase and a transporter for cytidine-5′-monophospho-sialic acid respectively, in human embryonic kidney 293 (HEK293) cells. In ClGALT1-SLC35A1-knockout (KO) cells, the expression of the Tn antigen showed a significant increase, whereas the expression of the T antigen (galactose-β1,3- N -acetylgalactosamine on serine or threonine residues) was decreased. Due to the inefficient secretion of soluble CA125, we employed a glycosylphosphatidylinositol (GPI) anchoring system. This allowed for the expression of GPI-anchored CA125 on the cell surface of ClGALT1-SLC35A1-KO cells. Cells expressing high levels of GPI-anchored CA125 were then enriched through cell sorting. By knocking out the PGAP2 gene, the GPI-anchored form of CA125 was converted to a secretory form. Through the engineering of O -glycans and the use of a GPI-anchoring system, we successfully produced CA125 with Tn antigen modification. [ABSTRACT FROM AUTHOR]

MHz switches and integrated magnetic planar transformers (PT) promote the high density and miniaturization of DC/DC converters. The parasitic parameters of the PT at high frequency significantly affect the performance of converters, resulting in severe electromagnetic interference (EMI) problems. Firstly, this paper proposes a new common‐mode (CM)‐suppression winding structure for the input series output parallel (ISOP) matrix transformer LLC converter. The sources and conduction principle of CM noise are analyzed. Furthermore, this optimization based on winding shape and position is simple and feasible, suppressing the CM noise significantly. Compared with conventional multilayer winding structure, this optimization increases the current‐carrying area by 2.8%–5.9%, effectively improving the primary current distribution. In addition, the proposed structure makes the best planar windings in footprint with expanded windings, bringing the simplest layout in the primary winding. Finally, a 1 MHz 400 V/12 V 300 W LLC converter is constructed to verify the effect of this winding structure. The results show that a 40% reduction in CM current can be achieved while maintaining the current balance. [ABSTRACT FROM AUTHOR]

Software defect prediction is a crucial discipline within the software development life cycle. Accurate identification of defective modules in software can result in time and cost savings for developers. The ELM algorithm offers the benefits of rapid training and robust learning capabilities. Numerous researchers in the field of software defect prediction have employed the ELM algorithm. However, the ELM algorithm, a single hidden layer feedforward neural network, faces challenges related to random parameter selection and limited generalization ability. To enhance the predictive performance of the ELM algorithm in software defect prediction. Most researchers utilize swarm intelligence optimization algorithms to optimize extreme learning machines. However, these optimization methods may encounter challenges related to fall into local optimal solution. This paper introduces a new sparrow search algorithm (2SSSA) built upon the original sparrow search algorithm. To enhance the original sparrow algorithm's ability to escape local extrema, the pinhole imaging reverse learning and somersault foraging strategies are employed. The performance of 2SSSA in terms of optimization and convergence speed is assessed using 8 randomly selected benchmark functions and 8 CEC2017 functions. Additionally, ensemble learning is a prominent research focus in the field of software defect prediction. Ensemble learning is known for its ability to significantly enhance prediction performance and model generalization. As a result, the ELM optimized using 2SSSA serves as the foundational predictor in the bagging ensemble learning algorithm. We propose an ensemble algorithm for software defect prediction, denoted as 2SSEBA, which employs a 2-step optimization sparrow algorithm (2SSSA) to optimize extreme learning machines. Based on an evaluation of 25 publicly available software defect prediction datasets using 5 commonly employed metrics. The predictive performance of 2SSEBA significantly outperforms the other five advanced prediction algorithms. Furthermore, this conclusion is supported by both Friedman ranking and Holm's post-hoc test. [ABSTRACT FROM AUTHOR]

A highly active PtNi-alloy catalyst (p-PtNi/KB) is synthesized using solution-plasma interaction. The plasma effect results in a substantial increase of active sites on the support surface. This facilitates the alloying and functionalization of supports, enabling achievement of enhanced catalytic activity and effective resolution of cost-related challenges in fuel cells. [ABSTRACT FROM AUTHOR]

Unilateral kidney hypoplasia is a congenital condition characterized by the underdevelopment of one kidney. Although often asymptomatic, it can cause severe renal complications in patients combined with contralateral renal injury, leading to acute renal failure. This case report describes a patient with unilateral kidney hypoplasia who underwent a kidney biopsy on the contralateral normal‐sized kidney and subsequently developed oliguric acute kidney injury. This report discusses the challenges encountered while diagnosing and managing this rare case, highlighting the importance of awareness and recognition to perform timely intervention and optimize the patient's outcome. [ABSTRACT FROM AUTHOR]

Highlights The quasi‐static tensile properties of carbon nanotube (CNT) films have been extensively investigated, yet research on their impact tensile properties at high strain rates remains scarce. In this article, CNT films prepared by floating catalyst chemical vapor deposition (FCCVD) method were densely arranged by chlorosulfuric acid (CSA) under wet stretching. The Instron 3365 and miniaturized split Hopkinson tension bar (SHTB) were used to conduct tensile testing at different strain rates. The findings reveal that CSA wet‐stretching markedly enhances the density and orientation of CNT films, resulting in significant improvements in tensile properties with a notable strain rate effect. Specifically, when immersed for 60 s under a draft ratio of 40% and a strain rate of 1900 s−1, the densified CNT films exhibit maximum stress and energy absorption values of 777.44 MPa and 54.79 MJ/m3, respectively, achieving a 637.1% and 425.7% increase compared with the original film. This research provides a convenient and feasible strategy to prepare CNT films with high energy absorption tolerance across various strain rates, thus expanding the practical application potential of CNT films. The study innovates a posttreatment way to produce superior FCCVD CNT films. CSA treatment and wet stretching enhance CNT films' mechanical properties. Dynamic fracture strength boosts over 600% and energy absorption raises over 400%. CSA can purify FCCVD‐prepared CNT films, greatly improving their properties. The Prep can be effectively integrated with the direct spinning process. [ABSTRACT FROM AUTHOR]

As an important aquatic prepared food, surimi products are favored by consumers due to their unique viscoelastic properties and high nutritional value. Gel properties are the main indicators to measure the quality of surimi products. The gelation of surimi mainly involves intramolecular (conformational change) and intermolecular (chemical force) changes. Factors such as processing treatments, raw fish species and exogenous additives affect surimi protein structure, chemical forces and endogenous enzyme activities, which further affect the gel properties of surimi products. This review focuses on the mechanism of surimi heat‐induced gel, mainly including protein chain expansion and aggregation through various chemical forces to form a three‐dimensional network structure. In addition, the mechanism and application of different factors on the gel properties of surimi were also discussed, providing a reference for the selection of fish species, the control of heating conditions in the gel process of surimi products, the selection of additives and other measures to improve the gel performance. [ABSTRACT FROM AUTHOR]

This paper proposes a secondary‐side semi‐active series resonant converter with hybrid control. Compared with the traditional series resonant converter (SRC), the converter only replaces two diodes with metal oxide semiconductor field effect transistors (MOSFETs) on the secondary side of the transformer, without adding any auxiliary components. By employing hybrid modulation scheme, the proposed converter can achieve a wide output voltage range in a narrow switching frequency range with high efficiency and has excellent soft‐switching performance. Due to the large magnetizing inductor and narrow switching frequency range, the proposed converter can achieve energy delivery with high efficiency and high power density. This paper provides a detailed introduction to the working principle, circuit characteristics, and design process of the converter. Finally, a 3.3 kW SiC‐based experimental prototype with 400 V input, 250–430 V output, and a switching frequency of 120–140 kHz is built to verify the theoretical analysis, and the peak efficiency reaches 97.82%. [ABSTRACT FROM AUTHOR]

In this paper, a control method combined with variable frequency and phase shifting is proposed, the primary purpose of which is to optimize the operating efficiency of the phase‐shift full‐bridge (PSFB) DC‐DC converter. By modeling the losses of the PSFB converter, the optimal switching frequency related to the load conditions is found. A neural network aided variable frequency controller that can work linearly is built to achieve the proposed method. At the same time, the voltage control loop is retained to ensure the stability of the output voltage and the necessary dynamic response of the converter. This paper builds an experimental platform for a 2 kW PSFB DC‐DC converter to verify the effectiveness of the proposed control method. With the control method proposed in this paper, the PSFB converter can always work at the optimum efficiency point under different load conditions. In addition, this paper also analyzes the influence of variable frequency control on PSFB operating states, such as zero‐voltage‐switching (ZVS) constraints, continuous conduction mode (CCM) operating states, and power density, which have an impact on its operating conditions. [ABSTRACT FROM AUTHOR]

Arylalkylamine N‐acetyltransferase (aaNAT) is a crucial enzyme that catalyses the transfer of acetyl groups from acetyl coenzyme A to arylalkylamines and arylamines. Evolutionary studies have identified a distinct class of aaNATs specific to mosquitoes, yet their functions remain elusive. This study focuses on Ae‐aaNAT7, a mosquito‐unique gene in Aedes aegypti (Diptera:Culicidae), to explore its functionality. Temporal and spatial expression analysis of Ae‐aaNAT7 mRNA revealed high expression during embryonic development and in first‐instar larvae, with notable expression in the limbs of adult mosquitoes based on tissue expression profiling. By further employing CRISPR/Cas9 technology for loss‐of‐function studies, our investigation revealed a reduction in the area of white spotting in the limbs of Ae‐aaNAT7 mutant adult mosquitoes. Further investigation revealed a significant decrease in the fecundity and hatchability of the mutants. Dissection of the ovaries from Ae‐aaNAT7 heterozygous mutants showed a noticeable reduction in the oocyte area compared with wild type. Dissection of the exochorion of the eggs from Ae‐aaNAT7 homozygous mutants consistently revealed a striking absence of mature embryos. In addition, RNA interference experiments targeting Ae‐aaNAT7 in males resulted in a reduction in fecundity, but no effect on hatchability was observed. These collective insights underscore the substantial impact of Ae‐aaNAT7 on reproduction and its pivotal contribution to adult limb pigmentation in Ae. aegypti. These revelations offer insights pivotal for the strategic design of future insecticide targets. [ABSTRACT FROM AUTHOR]

With the development of the high‐end equipment technology, the performance requirements of the internal gear pump (IGP) under high pressure are also increasing. However, the increase of working pressure will lead to the instability of gear pump performance in terms of volumetric efficiency, noise, reliability and so on, it is necessary to reasonably evaluate the reliability level of high‐pressure IGP. The reliability analysis of the high‐pressure IGP is carried out from the aspects of flow, noise, and gear strength in this paper. First, the output flow rate and far‐field flow‐induced noise of the high‐pressure IGP were obtained through fluid numerical simulation, and experimental verification was conducted. Then, based on the time‐varying meshing stiffness, backlash function and static transmission error of the gear pair, a nonlinear dynamic model of the internal meshing gear pair was established. The time‐varying meshing force was obtained through the dynamic model of the gear pair, and then the tooth contact stress and tooth root bending stress were obtained. Finally, considering the uncertain factors affecting the performance of the high‐pressure IGP, Latin hypercube sampling (LHS) combined with dendrite network (DD) was used for random response modeling. The performance reliability of the high‐pressure IGP, including output flow rate, far‐field flow‐induced noise, and the strength of gear pair, were estimated based on the fourth moment‐based saddlepoint approximation (FMSA). The reliability analysis results can provide a theoretical basis for the structural optimization design of the high‐pressure IGP. [ABSTRACT FROM AUTHOR]

Ship detection in synthetic aperture radar (SAR) images is widely applied in marine monitoring. In recent years, convolutional neural networks (CNNs) have made significant advances in SAR ship detection. However, the scene imbalance problem, i.e. much more offshore scenes than inshore scenes in SAR images, severely hampers the improvement of detection accuracy. In this article, we propose scene-aware data augmentation to address the problem. First, a novel concept, inshore rate, is introduced to estimate the land area percentage of various scenes in SAR images. We can divide image samples into inshore and offshore ones based on the inshore rate without manual category annotations. Second, to augment inshore samples, we synthesize dummy inshore images by cropping the ground truth bounding boxes (GT bboxes) from offshore images and pasting them onto inshore images. This offline data augmentation strategy can address the scene imbalance problem and improve detection accuracy. The experiments conducted on SAR Ship Detection Dataset (SSDD) and Large-Scale SAR Ship Detection Dataset (LS-SSDD) demonstrate the effectiveness of the proposed method in improving detection performance. [ABSTRACT FROM AUTHOR]

Oxidative coupling of methane (OCM) is a promising process of direct transformation of CH4 to ethylene instead of a complicated two-step process in terms of first forming syngas through reforming or partial oxidation and then producing ethylene with Fischer–Tropsch synthesis (FTS). Na2WO4 has been one of the most studied catalysts of OCM. Here we investigated how the introduced transition metal elements Co, Mn, or Mo to Na2WO4 could influence the catalytic performance of OCM on the supported Na2WO4. It is found that Co, Mn and Mo can obviously promote catalytic activity of transforming CH4 and selectivity for producing ethylene and ethane in OCM performed on Na2WO4 supported on microporous silicate-1 (S-1). A similar promotion of Co, Mn and Mo to the catalytic activity and selectivity in OCM performed on Na2WO4 was found when the Na2WO4 was supported on Matériaux de l′Institut Lavoisier-53(Al) [MIL-53(Al)]. X-ray absorption near edge structure (XANES) and extended X-ray absorption fine structure (EXAFS) spectroscopy studies of these catalysts with added transition metal Co, Mn or Mo show that these metals diffused into the lattice of Na2WO4, further suggesting that the promotional effect likely arises from modification of the active phase of the supported Na2WO4 during OCM. [ABSTRACT FROM AUTHOR]

Objectives: We previously analysed the preparedness to deliver a disease-modifying Alzheimer's treatment in the United Kingdom and predicted substantial wait times. This study updates the prediction for the National Health Service (NHS) in England, using an improved model and newer data. Methods: We reviewed published data on capacity for diagnosis of cognitive impairment combined with expert input and constructed a model for wait times to access from 2023 to 2043. The model tracks patients from initial evaluation in primary care, cognitive testing by a dementia specialist, confirmatory biomarker testing with positron emission tomography (PET) scans or examination of cerebrospinal fluid and infusion delivery. Capacity for specialist visits and PET scans are assumed to be capacity constrained, and cerebrospinal fluid testing and infusion delivery to be scalable. Results: Capacity constraints were projected to result in substantial wait times: patients referred to specialists based on a brief cognitive test, which is the current standard of care, would expect an overall initial wait times of 56 months in 2023, increasing to 129 months in 2029 and then falling slowly to around 100 months. Use of a blood test for the confirmation of Alzheimer's pathology as an additional triage step, would reduce wait times to around 17 to 25 months. Discussion: The NHS England lacks capacity to provide timely access to a disease-modifying treatment, which is estimated to result in significant wait times and potentially avoidable disease progression. Better diagnostic tools at initial evaluation may reduce delays. [ABSTRACT FROM AUTHOR]

The magnetization mechanism of Co-doped BaTiO3 ultrathin films is a subject of debate, which results in difficulties with the design of new multiferroics based on BaTiO3 matrixes. With the aid of a first-principles approach, it was observed that when the interstitial site and Ti vacancy were filled with Co, the configuration behaved in a nonmagnetic manner, indicating the significance of the Co content. Moreover, in the case of Co substituting two neighboring Ti atoms, when a direct current field was applied in the [100] direction, the magnetic domains excluding those in the [100], [010], and [001] directions were directed away. Further, the magnetoelectric constant was evaluated at ~449.3 mV/cmOe, showing strong magnetoelectric coupling at room temperature. Clearly, our study indicates that strict control of Ba, Ti, O, and Co stoichiometry can induce an electric and magnetic field conversion in two-dimensional BaTiO3 and may provide a new candidate for single-phase multiferroics for application in next-generation multifunctional devices. [ABSTRACT FROM AUTHOR]

When the resonant converters are connected in parallel, the output current is unbalanced without additional current‐sharing measures due to differences in resonant component. In the input‐parallel output‐parallel resonant converter system, the output voltage accuracy of the converter under the traditional droop control is analyzed when the load changes. In this paper, an adaptive droop control is proposed, in which the droop coefficient is adaptively adjusted as the load changes. The control method proposed in this paper realizes the current sharing between the converters and solves the shortcomings of the output voltage changing under different loads in the conventional droop control. Taking two parallel LLC converters as an example, the control block diagram of the parallel control method for adaptive adjustment of the droop coefficient proposed in this paper is given, and the stability of the control loop is analyzed. Finally, two parallel prototypes of LLC converters with input 200 V/output 24 V input are built by digital control, and the experiment shows that the proposed control method improves the shortcomings of excessive output voltage droop caused by traditional droop control during dynamic load switching, which verifies the effectiveness of the method. [ABSTRACT FROM AUTHOR]

The primary goal of this study is to examine the impact of sodium hydroxide (NaOH)/alkali-activated fly ash on the fresh properties and mechanical properties of self-compacting concrete (SCC). The fresh properties, known as the workability of SCC characteristics, were determined using the U-box, V-funnel, J-ring, and L-box tests. The M30 grade SCC containing superplasticizer of 0.86 wt. % of cement is replaced with 10%, 15%, 20%, 25%, 30%, and 40% of alkali-activated fly ash. On days 7, 14, and 28 after curing, the compressive strength and the splitting tensile strength of the SCC were examined. The study was further extended to evaluate the behavior of reinforced concrete beams containing fly ash and ground granulated blast furnace slag, whose size was 1200 × 100 × 150 mm3, under flexure loading. Based on the test results, it was found that the increase in the replacement of cement with alkali-activated fly ash increased the workability in the SCC. With the addition of superplasticizers, the SCC gained much more workability than conventional concrete containing no superplasticizer. The mechanical properties of 10% and 15% activated fly ash in Portland cement provided the maximum strength for the SCC at different ages of curing. The maximum first crack load and maximum ultimate flexure loading of the reinforced concrete beam containing 10% activated fly ash by weight of cement were greater than those of the control concrete beam. The microstructural scanning electron microscope observations confirmed that the alkali-activated fly ash increased the strength properties of the self-compacting concrete. [ABSTRACT FROM AUTHOR]

Ethylene-propylene block copolymer (EbP) is a vital component in impact polypropylene copolymer (IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work, four IPCs were investigated by atomic force microscopy-infrared (AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer (EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material. [ABSTRACT FROM AUTHOR]

Despite the promise of therapeutic antibodies in engaging the immune system to eliminate malignant cells, many aspects of the complex interplay between immune cells and cancer cells induced by antibody therapy remain incompletely understood. This study aimed to develop a biosensor system that can evaluate direct cell-cell physical contact and interactions between immune effector and target cells induced by therapeutic antibodies in physiologically relevant environments. The system uses two structural complementary luciferase units (SmBit and LgBit) expressed on the respective membranes of effector and target cells. Upon cell-cell contact, the two subunits form active NanoLuc, generating a luminescent signal, allowing for real-time monitoring of cell-cell interactions and quantitatively assessing the pharmacological effects of therapeutic antibodies. We optimized the system to ensure selectivity by adjusting the spacer lengths between two luciferase units to minimize interference from nonspecific intercellular contact. The system was applied to quantitatively monitor cell-cell interactions between NK and target cells induced by rituximab and between T and target cells induced by blinatumomab in a 3D cell culture system. The biosensor system has the potential to characterize antibody pharmacology through a deeper understanding of antibody-mediated cell-cell interactions. [ABSTRACT FROM AUTHOR]

An 8-year-old girl presented with a 34-day history of cough, fatigue, and impaired exercise tolerance. She experienced cyanosis on exertion but denied fever, hemoptysis, hematuria, or seizures. Her perinatal and family histories were unremarkable, and she had no history of exposure to TB. A chest radiogram from a local clinic showed diffuse pulmonary lesions. Tuberculin skin test, interferon-γ release assay, and HIV antibody test results were all negative. Immunoglobulin levels and lymphocyte subsets were normal. The patient did not respond to IV azithromycin for 1 week for community-acquired pneumonia. She was transferred to our hospital because of progressive respiratory distress and hypoxemia. [ABSTRACT FROM AUTHOR]

The uniaxial tensile mechanical properties of PVC foam considering the effects of strain rate ( ε ˙ = 0.0007 − 523 s − 1 ) and anisotropy (R = 1 − 1.57) have been investigated by quasi-static and dynamic (Split Hopkinson Tensile Bar, SHTB) tests. Combined high-speed camera system and Digital Image Correlation (DIC) technique, the real-time surface strain field of the specimen during the whole tensile process was obtained. On this basis, the macroscopic response and failure mode of PVC foam were investigated. The failure mechanism of PVC foam under tensile loading was revealed through Scanning Electron Microscope (SEM) images on fracture cross-section of loaded specimen. Finally, based on experimental data, a prediction equation on tensile strength of PVC foam considering the effects of strain rate and loading angle (anisotropy) is proposed. Furthermore, a nonlinear constitutive model is developed to describe the uniaxial tensile mechanical properties of PVC foam. [ABSTRACT FROM AUTHOR]

Oxidative stress is an important mechanism of aging, and in turn, aging can also aggravate oxidative stress, which leads to a vicious cycle. In the process of the brain converting light into visual signals, the eye is stimulated by harmful blue‐light radiation directly. Thus, the eye is especially vulnerable to oxidative stress and becomes one of the organs most seriously involved during the aging process. Cataracts, age‐related macular degeneration (AMD), glaucoma, diabetic retinopathy (DR), and dry eye are inextricably linked to the aging process and oxidative stress. Chlorogenic acid (CGA) has been demonstrated to have antioxidant and anti‐inflammatory activities, and its validity has been established experimentally in numerous fields, including cardiovascular disease, metabolic disorders, cancers, and other chronic diseases. There has previously been evidence of CGA's therapeutic effect in the field of ophthalmopathy. Considering that many ophthalmic drugs lead to systemic side effects, CGA may act as a natural exogenous antioxidant for patients to take regularly, controlling their condition while minimizing side effects. In this paper, in vitro and in vivo studies of CGA in the treatment of age‐related eye diseases are reviewed, and the prospects of CGA's antioxidant application for the eye are discussed. The aim of this review is to summarize the relevant knowledge and provide theoretical support for future research. [ABSTRACT FROM AUTHOR]

This study focuses on the effect of Cu doping on the thermoelectric properties of BiSbTe3 (BST) alloys. Firstly, we successfully prepared high-quality BST alloys using the KCl solvent method and selected the most promising BST(KCl)3.5 sample from them, followed by Cu doping experiments. The experimental results show that Cu doping significantly improves the crystal quality and density of the alloy, thereby increasing the material's mobility and reducing the resistivity, leading to an improvement in the power factor. However, Cu doping also introduces a large number of dislocations and lattice distortions. Additionally, the highly doped samples contain Cu2Te and BST superlattice structures, which further enhance the scattering of heat transfer phonons, significantly reducing the lattice thermal conductivity. In the experiment, Cu-doped samples exhibited extremely low lattice thermal conductivity, as low as 0.32 W m−1 K−1 at 300 K. These improvements in structure and performance have greatly enhanced the thermoelectric efficiency of Cu-doped samples, leading to a significant increase in their ZT values. Particularly, in samples with a Cu doping level of x = 0.01, the maximum ZT value was 1.47 at 400 K, and the average ZT value reached 1.28 in the temperature range of 300 K to 450 K. These findings underscore the wide-ranging application potential of Cu-doped BiSbTe3 alloys in room temperature refrigeration and power generation. The study provides crucial insights into the characteristics of Cu-doped BiSbTe3 alloys, while also contributing to the optimization of thermoelectric material design and the advancement of sustainable energy conversion technologies. [ABSTRACT FROM AUTHOR]

The presently available commercial photodetectors have a broadband photoresponse and require different external optical filters to block the undesired light outside the detection spectrum window, e.g., near-infrared (NIR) detection. The use of an NIR bandpass has technical limitations in curved or flexible large-area photodetectors, as an NIR bandpass depends critically on the difference in the interference of the optical path in the filter. This work reports the effort to develop a high-performance filter-free organic photodetector (OPD) with a double bulk heterojunction (BHJ) structure. The visible-blind NIR photodetection is realized by eliminating the photocurrent generated in the front visible light-absorbing BHJ optical depletion layer, due to the suppression of electron transport by incorporating a copper thiocyanate-based electron-blocking layer in the OPD. Only excitons generated in the rear NIR-absorbing BHJ contribute to photocurrent in the OPD, thereby achieving visible-blind NIR photodetection. The double BHJ OPD has a high responsivity of 0.38 A/W at 1050 nm and a specific detectivity of >1013 Jones over the wavelength range from 800 to 1050 nm, making it an ideal candidate for applications in optical communication, food quality detection, wellness monitoring, and NIR image sensors. [ABSTRACT FROM AUTHOR]

The construction of an interface has been demonstrated as one of the most insightful strategies for designing efficient catalysts toward electrochemical CO2 reduction (CO2RR). However, the weak interfacial interaction and inherent instability inevitably hinder a further performance enhancement in CO2RR attributable to the interface effect. Herein, 2 nm Ag nanoclusters (Ag NCs) are embedded onto CeO2 nanospheres (CeO2 NSs) with highly interconnected porosity (Ag NCs@CeO2 NSs) to exclusively study the pure interface effect toward CO2RR. The enhanced Ag–CeO2 pure interface endows Ag NCs@CeO2 NSs with a remarkably larger current density, significantly higher Faraday efficiency (FE), and energy efficiency as compared to Ag NCs, CeO2 NSs, and the one with Ag NCs dispersed on CeO2 nanoparticles. More importantly, an impressively high CO FE of over 70.0% is achieved at an ultralow overpotential (η) of 146 mV. The free energy and differential charge calculations, coupled with X‐ray photoelectron spectroscopy results jointly imply that the effective initiation of CO2RR to CO at a lower η over Ag NCs@CeO2 NSs derives from the enhanced interface‐induced charge delocalization, which enhances the electron transfer ability toward *COOH intermediate, thus overcoming the energy barrier demanded for the rate‐determining step. [ABSTRACT FROM AUTHOR]

This work presents the experimental characterization and improved model of multi-strand entangled metallic wire materials (MS-EMWMs). MS-EMWM is a novel damping material made of several strands of entangled wires using a modified manufacturing process. Six batches of specimens were fabricated and tested under quasi-static loading. Secant stiffness and loss factor were calculated to indicate the mechanical properties. The results showed that MS-EMWM has the characteristics of high damping energy dissipation compared to EMWM. A micro-multi-strand spiral spring model was proposed to predict the mechanical properties of MS-EMWM. The probability distribution of micro-spring pairs between wires was used to characterize the random combination of materials. According to the results, the improved model can effectively reflect the mechanical behavior of MS-EMWM. The mechanical properties of MS-EMWM were predicted by the coefficient matrix obtained by particle swarm optimization. Through the prediction and test results, the predicted results are acceptable. [ABSTRACT FROM AUTHOR]

Speaker identification based on deep learning is known to be susceptible to backdoor attacks. However, the current research on audio backdoor attacks is limited, and these attacks often use obvious noises as triggers, which can raise suspicion among users. In this paper, we introduce SilentTrig, a novel and imperceptible backdoor attack method targeted at speaker identification. Our approach involves utilizing an optimized steganographic network to embed triggers into benign audio samples and implementing a two-stage adversarial optimization process. This ensures that the poisoned samples are acoustically indistinguishable from their benign counterparts, resulting in a substantially improved attack imperceptibility. We evaluate SilentTrig on two datasets and four state-of-the-art models. The results demonstrate a high Attack Success Rate (ASR) of up to 99.2%, a Just Noticeable Difference (JND) of only 0.3, and resistance to typical defense methods such as Neural Cleanse and Fine-Pruning. • Backdoor attack against speaker identification, improving the imperceptibility. • Optimized steganographic network for embedding triggers secretively. • Two-stage adversarial optimization to get indistinguishable malicious samples. • Designed malicious samples are effective and stealthy for attacks. [ABSTRACT FROM AUTHOR]

Silicon nanophotonics has attracted significant attention because of its unique optical properties such as efficient light confinement and low non-radiative loss. For practical applications such as all-optical switch, optical nonlinearity is a prerequisite, but the nonlinearity of silicon is intrinsically weak. Recently, we discovered a giant nonlinearity of scattering from a single silicon nanostructure by combining Mie resonance enhanced photo-thermal and thermo-optic effects. Since scattering and absorption are closely linked in Mie theory, we expect that absorption, as well as heating, of the silicon nanostructure shall exhibit similar nonlinear behaviors. In this work, we experimentally measure the temperature rise of a silicon nanoblock by in situ Raman spectroscopy, explicitly demonstrating the connection between nonlinear scattering and nonlinear heating. The results agree well with finite-element simulation based on the photo-thermo-optic effect, manifesting that the nonlinear effect is the coupled consequence of the red shift between scattering and absorption spectra. Our work not only unravels the nonlinear absorption in a silicon Mie-resonator but also offers a quantitative analytic model to better understand the complete photo-thermo-optic properties of silicon nanostructures, providing a new perspective toward practical silicon photonics applications. [ABSTRACT FROM AUTHOR]

BiFeO3-BaTiO3 is a promising high-temperature lead-free piezo-ceramics due to its high Curie temperature (TC > 500 °C) and excellent piezoelectric properties. However, a high leakage current was often detected in this system, which severely affects its applications. In this work, the 0.7BiFe(1−x)GaxO3-0.3BaTiO3 (BFGax-BT, 0.00 ≤ x ≤ 0.10) system was designed to reveal the reason of leakage-current density decreased by their leakage mechanism. Because of the suppression of generation of Fe2+ and oxygen vacancy ( V O ∙ ∙ ), the leakage mechanism from space charge limited conduction mechanism found in Ga-free BF-BT ceramics turns into Ohmic conduction and Schottky emission mechanism as Fe3+ was replaced with Ga3+. A good combination of piezoelectric properties (d33 = 174 pC N−1 and kp = 29%) and high Curie temperature (TC = 497 °C) was achieved in the BFGa0.06-BT ceramic owning the lowest leakage-current density. This work will provide the clues for preparing the high insulation and high piezoelectric performance BF-BT-based ceramics by suppressing the valence change of Fe3+ and V O ∙ ∙ appearance. [ABSTRACT FROM AUTHOR]

Eukaryotic cells organize their genome within the nucleus with a double-layered membrane structure termed the nuclear envelope (NE) as the physical barrier. The NE not only shields the nuclear genome but also spatially separates transcription from translation. Proteins of the NE including nucleoskeleton proteins, inner nuclear membrane proteins, and nuclear pore complexes have been implicated in interacting with underlying genome and chromatin regulators to establish a higher-order chromatin architecture. Here, I summarize recent advances in the knowledge of NE proteins that are involved in chromatin organization, gene regulation, and coordination of transcription and mRNA export. These studies support an emerging view of plant NE as a central hub that contributes to chromatin organization and gene expression in response to various cellular and environmental cues. [ABSTRACT FROM AUTHOR]