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This study introduces a joint optimization algorithm that combines semidefinite relaxation (SDR) and particle swarm optimization (PSO) to efficiently estimate the maximized peak spatial-average APD (mpsAPD) by multiantenna user equipment (MAUE). Utilizing SDR, the algorithm computes the weight of the elements within the antenna array and employs PSO to identify the averaging area for maximum exposure. Quasi-conformal parameterization is utilized to facilitate searches along curved phantom profiles. The proposed approach exhibits superior efficiency and accuracy in calculating the mpsAPD by MAUE, revealing a negligible discrepancy of less than 3% relative to 10 000 times Monte Carlo simulations and reducing 97.5% of computational time. These findings provide substantial significance for the current discussion on international standardization concerning the assessment of APD.

A fundamental limitation of object detectors is that they suffer from “spatial bias”, and in particular perform less satisfactorily when detecting objects near image borders. For a long time, there has been a lack of effective ways to measure and identify spatial bias, and little is known about where it comes from and what degree it is. To this end, we present a new zone evaluation protocol, extending from the traditional evaluation to a more generalized one, which measures the detection performance over zones, yielding a series of Zone Precisions (ZPs). For the first time, we provide numerical results, showing that the object detectors perform quite unevenly across the zones. Surprisingly, the detector's performance in the 96% border zone of the image does not reach the AP value (Average Precision, commonly regarded as the average detection performance in the entire image zone). To better understand spatial bias, a series of heuristic experiments are conducted. Our investigation excludes two intuitive conjectures about spatial bias that the object scale and the absolute positions of objects barely influence the spatial bias. We find that the key lies in the human-imperceptible divergence in data patterns between objects in different zones, thus eventually forming a visible performance gap between the zones. With these findings, we finally discuss a future direction for object detection, namely, spatial disequilibrium problem, aiming at pursuing a balanced detection ability over the entire image zone. By broadly evaluating 10 popular object detectors and 5 detection datasets, we shed light on the spatial bias of object detectors. We hope this work could raise a focus on detection robustness.

In order to speculate the three-dimensional structure of the potential binding pocket of the chitin synthase inhibitor, a series of 2,4-diphenyloxazoline derivatives with different lengths of alkyl chains and heteroatoms were designed and synthesized by a homologous strategy. The bioassay results indicate that both the length of the alkyl chains and the type of substituents can affect the acaricidal activity against mite eggs. Compounds containing chloropropyl, alkoxyalkyl, and para-substituted phenoxyalkyl or phenylthioalkyl groups exhibit good activity, while those containing steric hindrance substituents or carbonyl substituents on the benzene ring exhibit reduced activity. Three-dimensional quantitative structure–activity relationship (3D-QSAR) study showed that there may be a narrow hydrophobic region deep in the pocket, and the steric effect plays a more important role than the electrostatic effect. The current work will provide assistance for future molecular design and target binding research.

The design and optimization of polymerization processes rely on accurate kinetic parameters of polymerization reactions since they have a significant impact on polymer properties. We develop a kinetic parameter estimation methodology for non-steady-state olefin polymerization processes. A dynamic model for olefin polymerization reaction kinetics based on the method of moments and instantaneous distribution method is established, which considers reaction temperature fluctuations and concentration variation during polymerization. Bayesian optimization (BO) algorithm is applied in the parameter estimation framework, where the kinetic model is treated as a black box function. The effectiveness of the method developed in this article was demonstrated through three cases, and the parameter estimation strategies used in other literature studies were compared. Additionally, we conduct a comparison of the fitting and extrapolation results obtained from diverse algorithms. Notably, BO emerges as a favorable alternative to deterministic algorithms, as it circumvents the challenges inherent in utilizing gradient-based optimization methods for complex polymerization dynamics models and is more suitable for scenarios with fast prediction in high-throughput experiments. Furthermore, using a dynamic kinetic model is crucial for kinetic parameter estimation in non-steady-state olefin polymerization, as it can reflect the dynamic changes with reaction temperature and concentrations.

Graphical Abstract:

• Binary reinforcements of networked Si 3 N 4 nws and interconnected GE in carbon fiber composites were constructed. • Networked Si 3 N 4 nws are uniformly distributed among the carbon fibers, while interconnected GE is firmly rooted on the surface of both networked Si 3 N 4 nws and carbon fiber. • Robust mechanical strength, excellent friction performances and outstanding anti-ablation properties of composites are realized. Carbon fiber (C f) reinforced pyrolytic carbon (PyC) composites simultaneously possessing robust mechanical strength, excellent friction performances and outstanding anti-ablation properties are demanded for advanced aerospace applications. Efficient architecture design and optimization of composites are prominent yet remain high challenging for realizing the above requirements. Herein, binary reinforcements of networked silicon nitride nanowires (Si 3 N 4 nws) and interconnected graphene (GE) have been successfully constructed into C f /PyC by precursor impregnation-pyrolysis and chemical vapor deposition. Notably, networked Si 3 N 4 nws are uniformly distributed among the carbon fibers, while interconnected GE is firmly rooted on the surface of both networked Si 3 N 4 nws and carbon fibers. In the networked Si 3 N 4 nws and interconnected GE reinforced C f /PyC, networked Si 3 N 4 nws significantly boost the cohesion strength of PyC, while GE markedly improves the interface bonding of both Si 3 N 4 nws/PyC and fiber/PyC. Benefiting from the synergistic reinforcement effect of networked Si 3 N 4 nws and interconnected GE, the C f /PyC have a prominent enhancement in mechanical (shear and compressive strengths increased by 119.9% and 52.84%, respectively) and friction (friction coefficient and wear rate reduced by 25.40% and 60.10%, respectively) as well as anti-ablation (mass ablation rate and linear ablation rate decreased by 71.25% and 63.01%, respectively). This present strategy for networked Si 3 N 4 nws and interconnected GE reinforced C f /PyC provides a dominant route to produce mechanically robust, frictionally resisting and ablatively resistant materials for use in advanced aerospace applications. [ABSTRACT FROM AUTHOR]

The associations of multimorbidity patterns with transitions between frailty states remain unclear in older individuals. We used data from the National Health and Aging Trends Study 2011–2019. Frailty was measured annually using the Fried frailty phenotype. Multimorbidity patterns at baseline were identified using latent class analysis based on 14 chronic conditions. We used the semi‐Markov multi‐state model to investigate the influences of multimorbidity characterized by condition counts and patterns on subsequent frailty transitions over follow‐ups. Among 9450 participants aged ≥65 years at baseline, 34.8% were non‐frail, 48.1% were pre‐frail and 17.0% were frail. Over a median follow‐up of 4.0 years, 16 880 frailty transitions were observed, with 10 527 worsening and 6353 improving. For 7675 participants with multimorbidity, four multimorbidity patterns were identified: osteoarticular pattern (62.4%), neuropsychiatric–sensory pattern (17.2%), cardiometabolic pattern (10.3%) and complex multimorbidity pattern (10.1%). Compared with no disease, multimorbidity was significantly associated with an increased risk of worsening transitions, including from non‐frail to pre‐frail (hazard ratio [HR] = 1.35; 95% confidence interval [CI] = 1.21–1.52), from non‐frail to frail (HR = 1.68; 95% CI = 1.04–2.73), from pre‐frail to frail (HR = 2.19; 95% CI = 1.66–2.90) and from pre‐frail to death (HR = 1.64; 95% CI = 1.11–2.41). Compared with the osteoarticular pattern, neuropsychiatric–sensory, cardiometabolic and complex multimorbidity patterns had a significantly higher risk of worsening frailty (all P< 0.05). Multimorbidity was associated with dynamic transitions between frailty states and death among older American adults, and the associations varied across multimorbidity patterns. The findings could offer significant implications for public health policymakers in planning interventions and healthcare resources. They also might inform clinicians regarding providing targeted clinical treatment and health management based on multimorbidity patterns of older people.

There are complicated sources of uncertainty in electromechanical systems, and only by comprehensively considering the uncertainties from electromagnetic parameters, mechanical structures, and loads can the vibration response of the system be better forecasted. A high-power electromechanical device directly powered by a permanent magnet synchronous motor is taken as the object of research, and a nonlinear dynamic electromechanical coupling model of the system is established. In the case of the primary parameter resonance, the multi-scale technique is then used to determine the first-order approximation solution and numerical methods are employed to investigate the stability. Under uncertain parameter conditions, the vibration response of a permanent magnet direct-drive system is further predicted using the multi-scale method and the Chebyshev interval method in combination. Meanwhile, the scanning method is employed to obtain the reference values to evaluate the performance of the proposed approach. Numerous numerical examples demonstrate that the primary resonance response is more susceptible to variations in the magnetic remanence of the permanent magnet material, current amplitude, internal power angle, and torsional stiffness. In addition, under the influence of multi-source parameter uncertainties, the peak and area of the primary resonance are highly variable, which greatly reduces the operation stability of the electromechanical system. These results can provide a theoretical reference for vibration response prediction and anti-resonance design of permanent magnet direct-drive systems with multi-source uncertainties.

The growth of dendrites in Li/Na metal batteries is a multifaceted process that is controlled by several factors such as electric field, ion transportation, temperature, and pressure. Rational design of battery components has become a viable approach to address this challenge. Among the various design strategies, heterogeneous structures have been demonstrated to be effective in mitigating uneven metal deposition by reducing the local current density and regulating the deposition sites. In this review, we discuss comprehensively the underlying principles and factors that influence dendrite growth, as well as the synthesis approaches for heterogeneous structures. Furthermore, we provide an overview of the diverse applications of heterogeneous structures in battery components. Finally, we highlight existing challenges and future directions for the use of heterogeneous structures in regulating metal deposition.

This short communication addresses the problem of elliptic localization with outlier measurements. Outliers are prevalent in various location-enabled applications, and can significantly compromise the positioning performance if not adequately handled. Instead of following the common trend of using M -estimation or adjusting the conventional least squares formulation by integrating extra error variables, we take a different path. Specifically, we explore the worst-case robust approximation criterion to bolster resistance of the elliptic location estimator against outliers. From a geometric standpoint, our method boils down to pinpointing the Chebyshev center of a feasible set, which is defined by the available bistatic ranges with bounded measurement errors. For a practical approach to the associated min–max problem, we convert it into the convex optimization framework of semidefinite programming (SDP). Numerical simulations confirm that our SDP-based technique can outperform a number of existing elliptic localization schemes in terms of positioning accuracy in Gaussian mixture noise. [ABSTRACT FROM AUTHOR]

In this article, we analyze the characteristics of current–voltage (I–V) curves of photovoltaic (PV) modules in the hotspot state, determine characteristic quantities for identifying specific hotspot state information in the utilized module, and establish an inverse solution model for estimating the normal module temperature according to the electrical characteristics of the module. We combine this inverse solution model with a heat balance model to estimate the temperature of a faulty cell and obtain the overall temperature distribution in the module. Finally, infrared data on hotspot modules collected at a power plant in Hubei are used to verify the feasibility and accuracy of the temperature estimation algorithm. The experimental results show that the proposed PV cell temperature estimation method can determine the temperature distributions in different module areas and provide technical support for module-associated fire warnings.

The effect of spectrum on the visibility of roadway lighting targets was investigated. The experiment focused on the relation between average visibility ratings and small target visibility (STS under installations that employed LED and HPS light sources. Achromatic targets were more visible under LEDs illumination conditions than under HPS illumination conditions. The results also suggest that the visibility of colored objects on the road was better under LEDs illumination conditions in comparison to HPS. The results cannot be generalized to all LED light sources, but are likely indicative of LEDs with similar spectral power distributions (SPDs). Relative visibility under source types with different SPDs, and which provide different luminance distributions, should merit consideration when selecting a light source for roadway lighting. Keywords--Roadway lighting, visibility, LEDs, HPS, STV, achromatic target, colored target., 1 INTRODUCTION Driving is a complex task, with driver error, especially visibility, contributing to most of road crashes [Sabey 1975]. Good vision is required to estimate automobile speed, see potential [...]

Li metal anodes (LMAs) has attracted extensive research interest because of its extremely high theoretical capacity (3860 mAh/g) at low redox potential (−3.04 V vs.standard hydrogen electrode). However, the extremely high chemical reactivity and the intrinsic “hostless” nature of LMAs bring about serious dendritic growth and dramatic volume change during the plating/strapping process, thus resulting in poor Coulombic efficiency, short lifespan, and severe safety concerns. Of various strategies, the construction of three-dimensional carbonaceous scaffolds for LMAs can substantially reduce the local current density, inhibit Li dendrite growth, and accommodate volume variation. Electrospinning is a simple yet effective strategy to fabricate carbon nanofibers (CNFs), which have been regarded as promising skeletons for LMAs, owing to their large surface areas, good electrical conductivity, and high porosity. In this Mini Review, we briefly introduce the fabrication of CNFs using electrospinning and the modification of CNFs. We highlight the recent advances in electrospun CNF skeletons for LMAs, including pure CNF and CNF-based composite scaffolds. Finally, we discuss the remaining challenges of electrospun CNF scaffolds for LMAs and provide possible solutions to push forward the advancement in this field.

ABSTRACTCellular metabolism caters to the energy and metabolite needs of cells. Although the role of the terminal metabolic enzyme LDHB (lactate dehydrogenase B) in the glycolysis pathway has been widely studied in cancer cells, its role in viral infection is relatively unknown. In this study, we found that CSFV (classical swine fever virus) infection reduces pyruvate levels while promotes lactate release in pigs and in PK-15 cells. Moreover, using a yeast two-hybrid screening system, we identified LDHB as a novel interacting partner of CSFV non-structural protein NS3. These results were confirmed via co-immunoprecipitation, glutathione S-transferase and confocal assays. Furthermore, knockdown of LDHBvia interfering RNA induced mitochondrial fission and mitophagy, as detected reduced mitochondrial mass. Upon inhibition of LDHB, expression of the mitophagy proteins TOMM20 and VDAC1 decreased and the ubiquitination of MFN2, a mitochondrial fusion mediator, was promoted. In addition, a sensitive dual fluorescence reporter (mito-mRFP-EGFP) was utilized to analyze the delivery of autophagosomes to lysosomes in LDHB inhibition cells. Furthermore, LDHB inhibition promoted NFKB signaling, which was regulated by mitophagy; meanwhile, infection with CSFV negated these NFKB anti-viral responses. Inhibition of LDHB also inhibited apoptosis, providing an environment conducive to persistent viral infection. Finally, we demonstrated that LDHB inhibition promoted CSFV growth via mitophagy, whereas its overexpression decreased CSFV replication. Our data revealed a novel mechanism through which LDHB, a metabolic enzyme, mediates CSFV infection, and provides new avenues for the development of anti-viral strategies.Abbreviations: 3-MA:3-methyladenine; CCCP:carbonyl cyanide 3-chlorophenylhydrazone; CCK-8:cell counting kit-8; CSFV:classical swine fever virus; DAPI:4′,6-diamidino-2-phenylindole; DMSO:dimethyl sulfoxide; EGFP:enhanced green fluorescent protein; FBS:fetal bovine serum; FITC:fluorescein isothiocyanate; GST:glutathione-S-transferase; HCV:hepatitis C virus; IFN:interferon; LDH:lactate dehydrogenase; MAP1LC3/LC3:microtubule associated protein 1 light chain 3; MFN2:mitofusin 2; MOI:multiplicity of infection; NFKB:nuclear factor kappa B subunit 1; NFKBIA:nuclear factor inhibitor alpha; NS3:nonstructural protein 3; NKIRAS2:NFKB inhibitor interacting Ras like 2; PRKN:parkin E3 ubiquitin protein ligase; PBS:phosphate-buffered saline; qRT-PCR:real-time quantitative reverse transcriptase polymerase chain reaction; RELA:RELA proto-oncogene, NF-kB subunit; shRNA: short hairpin RNA; siRNA: small interfering RNA; TCID50:50% tissue culture infectious doses; TEM:transmission electron microscopy; TNF:tumor necrosis factor; TOMM20:translocase of outer mitochondrial membrane 20; VDAC1:voltage dependent anion channel 1.

In order to improve the stability of low-speed and high-torque permanent magnet synchronous motor control in the shearer semi-direct cutting system under large load fluctuation and strong impact conditions, an improved model predictive torque control strategy based on duty cycle is proposed which can effectively reduce the flux and torque ripples and improve steady-state control performance. This method combines the separate process of the voltage vector selection and the duty cycle calculation through the predictive model combined with duty cycle. Then, the optimal voltage vector and its duration is selected simultaneously based on minimizing the cost function. In addition, in order to mitigates the computational burden of the proposed method, the voltage vectors in the finite control set is pre-selected using hysteresis comparator according to the motor operating status. Furthermore, the duty cycle pulse width modulation is introduced to obtain a fixed switching frequency of the inverter. The results of simulation experiments confirm that the proposed strategy can significantly reduce the flux and torque ripples and improve the steady state performance while maintaining fast dynamic response.

This paper is devoted to analyzing the codimension-2 bifurcations of a generalized three-dimensional (3D) jerk system which is jerk function with all quadratic and cubic terms. First, the locally stability of Bagdanov–Takens (double-zero) equilibrium is systematically investigated using the center manifold and normal form theory combined with some bifurcation theories, and under some certain parameter conditions, the Bagdanov–Takens equilibrium of this jerk system could be a saddle, a focus, a degenerate equilibrium or an equilibrium which neighborhood is formed from an elliptic sector and a hyperbolic sector on its two-dimensional center manifold. Second, some adequate parameter conditions for guaranteeing the occurrence of Hopf bifurcation, Bautin (degenerate Hopf) bifurcation and the stability of the Hopf equilibrium of this jerk system are given. Finally, numerical simulation is used to verify the above theoretical analyses.

In this work, in situmagnesium-based composite composed of nanoscale magnesium oxide (MgO), prepared by spark plasma sintering, shows significant plasticity and high strain hardening. During the strain-hardening stage, the incremental work-hardening exponent shows drastic fluctuations due to the pile-up and release of dislocations. The dislocation pile-up at the interface makes it possible to form dislocation cells. Mixed dislocations can be generated within the cells surrounding the MgO particles, which can interact with the stress field and effectively hinder the movement of dislocations, leading to an increase in dislocation density. What is more, grain boundaries have higher elastic modulus and hardness, which may lead to the appearance of microcracks and eventually intergranular fractures. Our results may shed some light on understanding the role of MgO particles in influencing the mechanical properties of Mg alloys and Mg-based composites, especially in work hardening.

A facilely catalytic approach to prepare weakly entangled ultra-high-molecular-weight polyethylene (UHMWPE) with a fine particle size is reported with the polyhedral oligomeric silsesquioxane (POSS)-modified MgCl2-based Ziegler–Natta catalyst. CO in situFTIR spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and N2adsorption and desorption experiments revealed that the POSSs can coordinate with the MgCl2(110) plane, acting as adhesives with a cage structure to be in situembedded into the MgCl2-based support. This in situembedding of POSS facilitated the uniform dispersion of POSS nanoparticles, contributing the isolation effect for active TiCl4sites in the molecular scale, thus synthesizing the weakly entangled UHMWPE with exceptional activities. Simultaneously, the MgCl2-based catalysts afforded UHMWPE particles with small sizes, where POSS-modified catalysts brought the UHMWPE particle size down to below 200 μm, thanks to their considerable activities. To the best of our knowledge, this is the first time that nascent UHMWPE with a less entangled state and a fine particle size was synthesized. This combination of structural advantages enables substantial improvements in the toughness/stiffness/strength balance of nascent UHMWPE, especially for the impact strength which can reach 113.6 kJ/m2with a relatively low molecular weight.

In this paper, we propose an susceptible–infectious–hospitalized–recovered (SIHR) epidemic model with a nonlinear hospitalization rate depending on the number of unoccupied hospital beds. Note that the number of all hospital beds is used as a measure of all available medical resources. The basic reproduction number is calculated using the next-generation matrix method. We analyze the existence of endemic equilibria and discuss the global stability of the disease-free equilibrium. Existence and stability of endemic equilibria indicate possible occurrences of bifurcations. We confirm the appearance of backward bifurcation, saddle–node bifurcation, Hopf bifurcation, and Bogdanov–Takens bifurcation using normal form theory and central manifold theory. Numerical simulations show that the dynamic behavior of the model undergoes a transition from forward bifurcation to backward bifurcation and saddle–node bifurcation when the number of total hospital beds is reduced. Our findings suggest that when the number of total hospital beds falls below a threshold, backward bifurcation will occur, meaning that the disease cannot be eliminated even if the basic reproduction number is below unity. Therefore, the number of hospital beds should be increased beyond the bed threshold during an outbreak of a disease, which has important implications for disease control. [ABSTRACT FROM AUTHOR]

As a promising energy storage device, sodium-ion batteries (SIBs) have received continuous attention due to their low-cost and environmental friendliness. However, the sluggish kinetics of Na ion usually makes SIBs hard to realize desirable electrochemical performance when compared to lithium-ion batteries (LIBs). The key to addressing this issue is to build up nanostructured materials which enable fast Na-ion insertion/extraction. One-dimensional (1D) nanocarbons have been considered as both the anode and the matrix to support active materials for SIB electrodes owing to their high electronic conductivity and excellent mechanical property. Because of their large surface areas and short ion/electron diffusion path, the synthesized electrodes can show good rate performance and cyclic stability during the charge/discharge processes. Electrospinning is a simple synthetic technology, featuring inexpensiveness, easy operation and scalable production, and has been largely used to fabricate 1D nanostructured composites. In this review, we first give a simple description of the electrospinning principle and its capability to construct desired nanostructures with different compositions. Then, we discuss recent developments of carbon-based hybrids with desired structural and compositional characteristics as the electrodes by electrospinning engineering for SIBs. Finally, we identify future research directions to realize more breakthroughs on electrospun electrodes for SIBs.

Although compounds with a 2-(2-arylphenyl) benzoxazole motif are biologically important, there are only a few methods for synthesizing them. Herein, we report an efficient method for synthesis of such compounds by means of cobalt-catalyzed C–H/C–H cross-coupling reactions. This method has a broad substrate scope and good tolerance for sensitive functional groups. In addition, we demonstrate that introducing a heteroarene moiety to biphenyl compounds enhanced their antifungal activity.

Ultrahigh-molecular-weight polyethylene (UHMWPE) with a low polydispersity exhibits excellently physical and mechanical properties. In this work, a polyhedral oligomeric silsesquioxane (POSS)-modified Ziegler–Natta catalyst has been explored to synthesize the UHMWPE with a narrow molecular weight distribution. Diffuse reflection infrared spectroscopy combined with CO as the molecular probe, X-ray photoelectron spectroscopy, and diffuse reflectance UV–vis spectroscopy are employed to trace the evolution of the catalyst structure based on the investigation of vibrational and electronic properties of molecules. The results demonstrate that the chemically grafted POSS molecules are distributed evenly on the silica surface at the molecular level. The POSS can capture the MgTi compounds through protonation with the residual silanols, acting as a vertical support for active sites. The resulting active sites grafted on the POSS present much stronger Lewis acidity and were less heterogeneous (only tetra-coordinated Mg2+species) in comparison to the active sites directly grafted or absorbed on the silica surface. This less heterogeneity of active sites enables to synthesize the UHMWPE with a much narrow distribution, reducing the molecular weight distribution from 6.7 to 3.9.

Ion transport in an artificial asymmetric nanoporous membrane, which is similar to biological ion channels, can be used for biosensing. Here, a dendrimer-Au nanoparticle network (DAN) is in situassembled on a nanoporous anodic aluminum oxide (AAO) surface, forming a DAN/AAO hybrid membrane. Benefiting from the high surface area and anion selectivity of DAN, the prepared DAN/AAO hybrid presents selective ion transport. Under a bias potential, a diode-like current–potential (I–V) response is observed. The obtained ionic current rectification (ICR) property can be tuned by the ion valence and pH value of the electrolyte. The rectified ionic current endows the as-prepared DAN/AAO hybrid with the ability of enhanced bioanalysis. Sensitive capture and detection of circulating tumor cells (CTCs) with a detection limit of 80 cells mL–1as well as excellent reusability can be achieved.

Solid-state lithium metal batteries require accommodation of electrochemically generated mechanical stress inside the lithium: this stress can be1,2up to 1 gigapascal for an overpotential of 135 millivolts. Maintaining the mechanical and electrochemical stability of the solid structure despite physical contact with moving corrosive lithium metal is a demanding requirement. Using in situ transmission electron microscopy, we investigated the deposition and stripping of metallic lithium or sodium held within a large number of parallel hollow tubules made of a mixed ionic-electronic conductor (MIEC). Here we show that these alkali metals—as single crystals—can grow out of and retract inside the tubules via mainly diffusional Coble creep along the MIEC/metal phase boundary. Unlike solid electrolytes, many MIECs are electrochemically stable in contact with lithium (that is, there is a direct tie-line to metallic lithium on the equilibrium phase diagram), so this Coble creep mechanism can effectively relieve stress, maintain electronic and ionic contacts, eliminate solid-electrolyte interphase debris, and allow the reversible deposition/stripping of lithium across a distance of 10 micrometres for 100 cycles. A centimetre-wide full cell—consisting of approximately 1010MIEC cylinders/solid electrolyte/LiFePO4—shows a high capacity of about 164 milliampere hours per gram of LiFePO4, and almost no degradation for over 50 cycles, starting with a 1× excess of Li. Modelling shows that the design is insensitive to MIEC material choice with channels about 100 nanometres wide and 10–100 micrometres deep. The behaviour of lithium metal within the MIEC channels suggests that the chemical and mechanical stability issues with the metal–electrolyte interface in solid-state lithium metal batteries can be overcome using this architecture.

Sodium-ion capacitors (SICs) have shown great potential to combine the merits of high-power capability of traditional capacitors and high energy capability of batteries. However, the sluggish kinetics and inferior stability of conventional sodium-ion storage anode materials are major challenges for the practical utilization of SICs. In this work, interconnected urchin-like hollow Na2Ti3O7(Na2Ti3O7-IcUH) chains were designed and prepared by a simple one-step template-assisting method. Through a variety of controlled experiments, we explored how to effectively engineer the crystal-oriented growth and string the urchin-like spheres together. Benefiting from its urchin-like hollow structure and fully exposed (001) facet, the resulting Na2Ti3O7-IcUH exhibits a superior rate capability of 96.2 mA h g–1at 5 A g–1. Meanwhile, the interconnected three-dimensional primary structure endows Na2Ti3O7-IcUH with excellent cyclic stability (15% capacity loss at 5 A g–1after 2000 cycles). By coupling with commercial active carbon, the assembled SIC successfully demonstrates a energy density of 134.3 W h kg–1at a power density of 125 W kg–1and 38.2 W h kg–1at a high-power density of 2500 W kg–1, as well as a superior capacity retention of 75% after 2000 cycles at 2 A g–1within 1–4 V.

Chain entanglement was very important for adjusting the processability and mechanical property of nascent ultrahigh molecular weight polyethylene (UHMWPE). So far, it is still a mystery to unravel the formation mechanism of entanglements when the ethylene polymerization is conducted by the heterogeneous catalysts. In this study, a series of weakly entangled UHMWPE was synthesized by the polyhedral oligomeric silsesquioxane/MgCl2nanoaggregates modified Ziegler–Natta catalysts. The structure of nanoaggregates was evaluated by X-ray photoelectron spectroscopy, density functional theory simulations, and scanning probe microscope experiments, where the coordination strategy of MgCl2and hydroxyl of POSS was investigated. These nanoaggregates presented extremely low activity on ethylene polymerization and were proved to serve as isolators for separating the active sites and growing chains. The entanglement density of nascent UHMWPE (reflected by the value of initial storage modulus G′(t=0)) was exponentially decayed with the polymerization activity of increased numbers of nanoaggregates. Importantly, this exponentially decayed effect contributed by increased numbers of POSS/MgCl2isolators offset the rapid power function increment of entanglements upon rising the temperature, which was the essential reason for the successful synthesis of weakly entangled UHMWPE even at 85 °C. Finally, we have proposed the dependence and sensitivity of G′(t=0)(i.e., indicating the initial entanglement density of nascent polymers) on the polymerization activity, which was able to trace the formation of entanglements during polymerization through the POSS modified heterogeneous catalyst.

Corneal endothelium (CE) is a monolayer of mitochondria-rich cells, critical for maintaining corneal transparency compatible with clear vision. Fuchs endothelial corneal dystrophy (FECD) is a heterogeneous, genetically complex disorder, where oxidative stress plays a key role in the rosette formation during the degenerative loss of CE. Increased mitochondrial fragmentation along with excessive mitophagy activation has been detected in FECD; however, the mechanism of aberrant mitochondrial dynamics in CE cell loss is poorly understood. Here, the role of oxidative stress in mitophagy activation in FECD is investigated. Immunoblotting of FECD ex vivospecimens revealed an accumulation of PINK1 and phospho-Parkin (Ser65) along with loss of total Parkin and total Drp1. Similarly, modeling of rosette formation with menadione (MN), led to phospho-Parkin accumulation in fragmented mitochondria resulting in mitophagy-induced mitochondrial clearance, albeit possibly in a PINK1-independent manner. Loss of PINK1, phospho-Drp1, and total Drp1 was prominent after MN-induced oxidative stress, but not after mitochondrial depolarization by carbonyl cyanide m-chlorophenyl hydrazone. Moreover, MN-induced mitophagy led to degradation of Parkin along with sequestration of Drp1 and PINK1 that was rescued by mitophagy inhibition. This study shows that in FECD, intracellular oxidative stress induces Parkin-mediated mitochondrial fragmentation where endogenous Drp1 and PINK1 are sequestered and degraded by mitophagy during degenerative loss of post-mitotic cells of ocular tissue.

The electrolyte plays an essential role in the advancement of lithium–sulfur batteries (LSBs), as it not only transports the charge carriers but also extensively influences sulfur conversion mechanisms and electrode–electrolyte interphases formed on the electrode surface, thereby directly impacting battery performance. However, the majority of existing electrolytes suffer from incompatibility with either the Li anode or the sulfur cathode. Here, we develop a densely packed ion-cluster electrolyte (DPIE) through the strategic combination of a weakly solvating solvent and an inert diluent, resulting in the self-assembly of abundant compact ion-pair aggregates within its structure. This peculiar solvation structure promotes fast Li+desolvation, the formation of robust electrode–electrolyte interphases, and the suppression of polysulfide dissolution. Leveraging the tailored DPIE, room-temperature Li||sulfurized polyacrylonitrile (SPAN) batteries demonstrate 300 stable cycles with a capacity retention of 97.8% and a steady Coulombic efficiency exceeding 99.9%. Even under a limited negative/positive areal capacity ratio of four, the Li||SPAN cells exhibit good stability over 250 cycles with 97.1% capacity retention. Furthermore, Li||SPAN batteries show impressive stability over a wide temperature range spanning from −20 to 60 °C and exhibit reversibility at −10 °C over 200 cycles. This electrolyte design enables LSBs with prolonged operational lifetimes, rapid charging capabilities, and expanded temperature tolerance.

The aim of this paper is to investigate the stochastic asymptotic stability of semi-Markov switched systems with mixed impulses. A novel definition of average impulse gain is given to estimate the intensity of the mixed impulses. Based on the multiple Lyapunov function approach and average impulse interval method, we provide sufficient conditions on the stochastic asymptotic stability for the semi-Markov switched system with impulses. Moreover, the influence of impulses on the system is estimated by applying the average impulse gain and average impulse interval method, which are not only suitable for synchronous impulses but also for asynchronous impulses. The theoretical results are demonstrated by two examples. • We contain mixed impulses into the model and obtain sufficient conditions to ensure the stochastic asymptotic stability for the semi-Markov switched systems. • To measure the influences of mixed impulses, average impulse gain and average impulse interval method are applied. • We investigate the influence of the stationary distribution of the embedded Markov chain to the stochastic stability of the system and our result is sharper compared with Wang and Zhu (2018). [ABSTRACT FROM AUTHOR]

The safety and efficacies of laparoscopic radical procedures are still controversial for locally advanced pathological T4 (pT4) TCC (transverse colon cancer). Therefore, the aim of this study is to evaluate the oncologic and perioperative outcomes and to recognize the prognostic factors in radical resection for pT4 TCC derived from multi-center databases. 314 patients with TCC who underwent radical resection between January 2004 and May 2017, including 139 laparoscopic resections and 175 open resections, were extracted from multicenter databases. Oncological as well as perioperative outcomes were investigated. The baseline characteristics of the 2 groups did not differ significantly. Nevertheless, the laparoscopic technique was found to be linked with a significantly longer duration of surgery (208.96 vs 172.89 minutes, P = .044) and a significantly shorter postoperative hospital stay (12.23 vs 14.48 days, P = .014) when compared to the conventional open approach. In terms of oncological outcomes, lymph node resection (16.10 vs 13.66, P = .886), 5-year overall survival (84.7% vs 82.7%, P = .393), and disease-free survival (82.7% vs 83.9%, P = .803) were similar between the 2 approaches. Based on multivariate analysis, it was determined that differentiation and N classification were both independent prognostic factors for overall survival. However, it was found that only N classification was an independent prognostic factor for disease-free survival. These findings underscore the significance of differentiation and N classification as key determinants of patient outcomes in this context. Overall, the laparoscopic approach may offer advantages in terms of shorter hospital stays, while maintaining comparable oncological outcomes. Laparoscopic radical procedure can gain a couple of short-term benefits without reducing long-term oncological survival for patients with pT4 TCC.

Highlights • A new non-dimensionalization method is carried out. • Global stability of equilibria is established by employing Lyapunov functions. • Stability switches can occur. • There are supercritical/subcritical Hopf bifurcation. • Quantities with clear biological meanings are introduced to better understand the results from the view of biology. Abstract This paper concerns with a stage-structured predator-prey model with cannibalism in the predator, where the predator population is divided into two stages, a juvenile stage and a mature stage. The effects of cannibalism on the model have been partially discussed by Magnússon [12] and Mařík and Přibyloná [13] by means of numerical simulation and simple mathematical analysis. Here we reinvestigate the dynamics of this model. We obtain the global stability of the model, illustrate the effects of the two factors (one describes the cannibalization and the other the benefit from cannibalism) on dynamics of the model, and find that the positive equilibrium can undergo stability switch (from stable to unstable to stable, or from unstable to stable to unstable) with the change of the cannibalization rate. The obtained results indicate that large cannibalization rate can make the positive equilibrium globally stable although its stability would change with the increase of the rate. We also analyze theoretically Hopf bifurcation. It turns out that supercritical/subcritical Hopf bifurcation can occur with the rates of the above mentioned two factors as bifurcation parameters. Finally, we introduce some quantities with clear biological meanings to better understand our results from the point of biology. [ABSTRACT FROM AUTHOR]

Rational design of Li-S batteries requires efficient prevention of sulfur mobility and fast redox kinetics while accommodating the volumetric expansion of the sulfur cathode. Herein, we propose a multifunctional Chinese knot-like electrode design for advanced Li-S batteries. NiCo2S4nanotubes are closely interwoven to form Chinese knot-like designs as a sulfur host. The unique interconnectivity of the 2D Chinese knot-like networks constructed by 1D nanostructured nanotubes enables fast electron transfer for high capacity. Furthermore, the hollow structure can simultaneously provide enough space for volumetric expansion of sulfur and confine lithium polysulfides (LiPSs) in the internal void space by structural encapsulation. Besides these, experimental and theoretical analysis demonstrates that NiCo2S4can effectively capture the LiPSs and then catalyze the captured LiPSs into solid Li2S2/Li2S. More importantly, the transition between low-spin and high-spin of Co ions, induced by extra sulfur atoms from LiPSs, provides an electronic way to stabilize the adsorption system and reduce system energy, leading to the inhibition of the shuttle effect in Li-S batteries. As a result, the Chinese knot-like S@NiCo2S4electrodes show a high capacity of 1348 mA h g−1at 0.1 C and long cycling life up to 1000 cycles with a slow capacity decay of 0.02% per cycle at 1 C. Even with a higher sulfur loading of 5 mg cm−2, the electrodes still deliver good electrochemical performance.

A vector-borne disease model with general incidence rates is proposed and investigated in this paper, where both vector and host are stratified by infection ages in the form of a hyperbolic system of partial differential equations coupled with ordinary differential equations. The existence, uniqueness, nonnegativeness, and boundedness of solution of the model are studied for biologically reasonable purpose. Furthermore, a global threshold dynamics of the system is established by constructing suitable Lyapunov functionals, which is determined by the basic reproduction number $$\mathcal {R}_0$$ R0 : the infection-free equilibrium is globally asymptotically stable when $$\mathcal {R}_0<1$$ R0<1 while the endemic equilibrium is globally asymptotically stable when $$\mathcal {R}_0>1$$ R0>1 .

High-energy-density lithium (Li) metal batteries are a promising next-generation energy storage system but suffer from uneven Li deposition, anode material volumetric expansion, and the formation of “dead lithium”. To address these challenges, a three-dimensional (3D) lithiophilic manganese oxide@biomass-derived carbon nanofiber (MnO@BDCNF) host was prepared using waste cow leather as the precursor. The 3D lithiophilic MnO@BDCNF is capable of reducing local current density and suppressing the growth of lithium dendrites. As a consequence, the MnO@BDCNF host displays small overpotentials, stable polarization profiles, and high Coulombic efficiencies under various current densities and deposition capacities. When lithium iron phosphate (LiFePO4) is used as the cathode, the assembled Li/MnO@BDCNF||LiFePO4full cells deliver remarkable cycling stability with a capacity retention rate of 99.5% for 120 cycles. This work provides a viable approach for converting solid waste into a high-value-added host for lithium metal anodes.

Objective To evaluate the combined diagnostic value of two serum osteoarthritis (OA) markers and quantitative magnetic resonance imaging (MRI) evaluation of the cartilage volume of the tibial plateau in a canine model of experimental OA.Methods A total of 18 male Beagle dogs were used in this longitudinal study. OA was surgically induced via anterior cruciate ligament transection (ACLT) of the right knee in 10 dogs. The remaining eight dogs formed the sham operation control group and underwent the same procedure without ACLT. At various times after surgery, enzyme-linked immunosorbent assay was used to measure serum C-telopeptide of type II collagen (CTX-II) and type X collagen (ColX) levels. Quantitative evaluation of the tibial plateau volume was undertaken using MRI and ImageJ software.Results The serum CTX-II levels were significantly higher in the OA group at weeks 8, 12 and 16 after surgery, but not at week 4, compared with the control group. The serum ColX levels in the OA group were significantly higher than in the control group at weeks 8 and 12. The tibial plateau cartilage volumes in the OA group were significantly lower than in the control group at weeks 8 and 16.Conclusion Serum CTX-II and ColX levels combined with quantitative MRI evaluation of the tibial plateau cartilage volume in a canine model of OA demonstrated the potential to detect and monitor OA progression.

Numerous clinical trials have examined the role of anthocyanins on cardiometabolic health, but their effects have not been quantitatively synthesized and systematically evaluated. The aim of our study was to conduct a systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of anthocyanins on glycemic regulation and lipid profiles in both healthy populations and those with cardiometabolic diseases. The MEDLINE, EMBASE, Cochrane database, OVID EBM Reviews, and clinicaltrials.govdatabases were searched until February 2017. RCTs with a duration of ≥2 wk that evaluated the effects of anthocyanins on glycemic control, insulin sensitivity, and lipids as either primary or secondary outcomes were included. The Cochrane Risk of Bias tool was used to assess the study quality. Standardized mean differences (SMDs) were determined by random-effects models. Meta-regression, sensitivity, and subgroup analyses were performed to explore the influence of covariates on the overall effects. Thirty-two RCTs (1491 participants) were eligible for meta-analysis. Anthocyanins significantly reduced fasting glucose (SMD: −0.31; 95% CI: −0.59, −0.04; I2= 80.7%), 2-h postprandial glucose (SMD: −0.82; 95% CI: −1.49, −0.15; I2= 77.7), glycated hemoglobin (SMD: −0.65; 95% CI: −1.00, −0.29; I2= 72.7%), total cholesterol (SMD: −0.33; 95% CI: −0.62, −0.03; I2= 86.9%), and LDL (SMD: −0.35; 95% CI: −0.66, −0.05; I2= 85.2%). Sensitivity analyses showed that the overall effects remained similar by excluding the trials with a high or unclear risk of bias. The significant improvements in glycemic control and lipids support the benefits of anthocyanins in the prevention and management of cardiometabolic disease. Further well-designed RCTs are needed to evaluate the long-term effects of anthocyanins on metabolic profiles and to explore the optimal formula and dosage. The protocol for this review was registered at https://www.crd.york.ac.uk/PROSPERO/#index.phpas CRD42016033210.

Although lithium-sulfur batteries show fascinating potential for high-capacity energy storage, their practical applications are hindered by the fast capacity decay and low sulfur utilization at high sulfur loading. Herein we report an efficient sulfur host based on two oxides, in which SiO2hollow spheres with radial meso-channels are covered by a thin TiO2coating. SiO2spheres not only yield high sulfur loading as high as 80wt% but also possess strong lithium polysulfides (LiPS) adsorption capability. The thin TiO2coating can effectively prevent the LiPS outward diffusion, giving rise to a long-term stability. Meanwhile, the oxide-supported carbon from the carbonization of surfactants enables good electrical conductivity to facilitate electron access and improve sulfur utilization. Experimental and theoretical studies show the strong adsorption of LiPS by SiO2. Benefitting from the unique structural and compositional advantages, we achieve a high sulfur loading up to 80wt% with ~65.5% and 33% capacity retentions over 500 and 1000 cycles when tested at 0.5C and 1C, respectively.

We propose an SEI epidemic model for plant diseases, which incorporates disease latency, disease-caused removal, and constant recruitment in both susceptible and exposed classes. Because of the recruitment and disease-caused removal, the total population is varying. It is shown that the model only has an endemic equilibrium and the equilibrium is globally stable.

High-performance and easy-processing UHMWPE products with less entanglement and small particle size are difficult to synthesize efficiently in the polymerization process. In this study, a mixture of heptane and light paraffin is proposed as the polymerization medium to control the concentration of ethylene in the slurry during polymerization. Influences of the mixture composition on the polymerization behavior of ethylene, the particle size and its distribution of nascent UHMWPE, and the initial entangled state of UHMWPE were explored. Experimental results showed that as the volume fraction of heptane decreased, the viscosity of the solvent mixture increased exponentially, and ethylene solubility as well as mass transfer coefficient of ethylene in solvent decreased, which greatly affected the ethylene polymerization rate. By adjusting the volume fraction of heptane in the polymerization medium, the particle size, initial entanglement state density, and molecular weight of nascent UHMWPE will be coordinately controlled. UHMWPE with smaller particle size, lower entanglement density, and higher molecular weight can be prepared using the conventional Ziegler–Natta catalyst and polymerization medium with a lower heptane content, and its sintered UHMWPE material shows good mechanical properties.

The refined fluorosilicone microdroplets were introduced during the ethylene slurry polymerization to reduce the chain entanglement of ultra-high-molecular-weight polyethylene (UHMWPE) through the intermittent dormancy of living polymer chains. The dormancy effect is endowed by the highly frequent collisions between microdroplets and growing PE particles to block the transfer channel of reactants on the particle surface. The dwell time of microdroplets on the particle surface is an order of magnitude higher than that of the microbubbles, and the increase rate of the chain entanglement degree with the polymerization activity controlled by microdroplets is 2 orders of magnitude smaller than that of the microbubbles, indicating that fluorosilicone microdroplets have a better effect on the reduction of the chain entanglement. Compared with commercial products, the UHMWPE prepared in this work shows a lower chain entanglement degree and better mechanical properties, indicating that reducing the entanglement degree is one of the important means to improve the mechanical properties of UHMWPE.

With influenza as a prototype, we propose a compartmental model for a pandemic by taking into account of recruitment. The model has a threshold dynamics. Precisely, when the basic reproduction number R0⩽1, the disease free equilibrium is globally asymptotically stable; when R0>1, the disease free equilibrium is unstable and there is a unique endemic equilibrium which globally attracts all solutions except the trivial one (the disease free equilibrium). These results are established by applying the LaSalle’s invariance principle.

Little seems to be known about hyperchaotic systems with a curve of equilibria. Based on the classical Lorenz system, this paper proposes a new four-dimensional Lorenz-type hyperchaotic system which has a curve of equilibria. This new system can generate not only hyperchaotic attractors but also chaotic, quasi-periodic and periodic attractors, as well as singular degenerate heteroclinic cycles. Of particular interest is the observation that there are four types of coexisting attractors of this new hyperchaotic system: (i) chaotic attractor and quasi-periodic attractor, (ii) chaotic attractor and singular degenerate heteroclinic cycle, (iii) periodic attractor and singular degenerate heteroclinic cycle, and (iv) different periodic attractors. Furthermore, many singular degenerate heteroclinic cycles are found, which may lead to complex dynamics of hyperchaotic system with a curve of equilibria. [ABSTRACT FROM AUTHOR]

Urban wastewater contains a wide range of pathogens and antibiotic resistance genes (ARGs), which are a serious concern if reusing treated wastewater. However, few studies have explored the microbial communities in reclaimed water using ultraviolet (UV)/chlorine treatment and assessed the changes of the resistome. This study investigated the occurrence of typical pathogens, ARGs, and bacterial communities in UV/chlorine-treated reclaimed water samples. The numbers of culturable and viable but non-culturable pathogens were effectively reduced to 0 CFU/mL within 1–10 and 10–30 min after UV/chlorine treatment, respectively. Meanwhile, the physicochemical indices of water quality were not affected. UV/chlorine treatment could significantly change the bacterial community structure of reclaimed water, showing a decrease in bacterial abundance and diversity. Chlorine-resistant Acinetobacterand Mycobacteriumwere the dominant bacterial genera (> 50%) after UV/chlorine treatment. Moreover, the number of ARGs and mobile genetic elements (MGEs) decreased with an increase in UV/chlorine exposure. However, eight ARGs and three MGEs were consistently detected in more than three seasons, making these major concerns because of their potential role in the persistence and dissemination of antibiotic resistance. Overall, the results of this study suggest that UV/chlorine treatment can potentially improve the microbiological safety of reclaimed water. And more attention should be paid to the pathogens that are both chlorine-resistant and carry MGEs because of their potential for resistance transmission.

Novel architectured LiFePO4(LFP) that consisted of ordered LFP nanocubes was prepared through a facile hydrothermal method using polyethylene glycol (PEG) as a surfactant. The micro/nanostructured LFP with various morphologies ranging from cube cluster to rugby-like structure was synthesized via controlling the pH values of the precursor. A reasonable assembly process elucidating the formation of the hierarchical structure is also provided based on the experimental results. After a combination of carbon (C) coating and reduced graphene oxide (RGO) wrapping, the obtained LFP/C/RGO composites exhibit enhanced electrochemical performance compared to that of blank LFP synthesized under the same condition. Among as-synthesized cube-cluster-like, dumbbell-like, rod-like, and rugby-like composites, the rugby-like LFP/C/RGO reveal the best electrochemical properties with the discharge specific capacity of ∼150 mA h g–1after 100 cycles and a high reversible specific capacity of 152 mA h g–1at 0.1 C. The prepared LFP/C/RGO composite can be a promising cathode material for high energy, low cost, and environmentally friendly lithium-ion batteries.

From the perspectives of the energy band theory, the bond order-length-strength correlation, the local-bond-averaging approach, and the core–shell configuration for nanostructures, we have reconciled the effect of solid dimension and temperature of operation on the band gap of semiconductors by formulating the band gap as a function of the Hamiltonian and its perturbation by the response of the length and energy of the representative bond to the sample dimensionality and the applied temperature. Theoretical reproduction of the observations of Si, Ge, GaN, AlN, ZnO, ZnSe, and ZnS crystals confirmed that the size tunability of the band gap originates from the skin-region local bond relaxation and the associated quantum entrapment of binding energy. The extent of the EGchange depends on the tunable fraction of the undercoordinated atoms in the skin up to two atomic layers in depth. The temperature dependence of the band gap arises from bond expansion and weakening, with the opposite trends to that induced by size reduction. Furthermore, modeling reproduction of the temperature dependence has led to quantification of the atomic cohesive energy and Debye temperature of the specimen.

Abstract: A two-dimensional transient model has been developed to describe the catalytic methane reforming (MSR) coupled with simultaneous CO2 removal by different absorbents under non-isothermal, non-isobaric and non-adiabatic operating conditions. The influences of temperature, pressure and steam/carbon (S/C) on enhancement were taken into account. The results showed that the hydrogen mole fraction (dry basis) higher than 94% could be achieved using Li4SiO4, CaO, and HTC as CO2 acceptors at the operating conditions of 550°C and 0.1 MPa. When the reaction temperature varied from 500°C to 600°C, the initial CO2 capture rates were HTC>CaO>Li4SiO4>Li2ZrO3, and the saturation rates HTC>CaO>Li4SiO4>Li2ZrO3. Increasing the reaction temperature would improve the CO2 capture rate and available CO2 capacity. For Li4SiO4, although the adsorbing rate increased as the operating temperature increased, the capacity almost did not change. At 550°C, increasing the working pressure could promote the enhancing factors of Li4SiO4,Li2ZrO3 and HTC. There was an optimal steam/carbon ratio between 2–4.5 such that all CaO, Li4SiO4, HTC and Li2ZrO3 would obtain the biggest enhancement for H2 production at the pre-breakthrough stage.