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The existing impulsive consensus algorithms for second-order Lipschitz nonlinear multi-agent systems require to apply the impulsive control to both position and velocity vectors at the same time. Such a requirement cannot be met in most of the real-world applications. To overcome the limitations of these impulsive algorithms, two kinds of new second-order impulsive consensus algorithms using only velocity regulation are proposed. Through developing a weighted discontinuous Lyapunov function-based approach that is able to leverage the spectral property of Laplacian matrix, impulse-dwell-time-dependent sufficient conditions for solving second-order impulsive consensus are derived in the form of linear matrix inequalities. Further, it is shown that if the impulsively controlled velocity subsystems are globally exponentially stable, the impulsive static consensus algorithm is able to ensure that all agents tend to an agreed position. Based on the consensus conditions, two convex optimization problems are formulated, by which the impulsive gain matrices for ensuring a prescribed exponential convergence rate can be designed. Finally, the effectiveness of the proposed distributed impulsive consensus algorithms is certified through numerical simulations. • Impulsive consensus algorithms based on velocity regulation are proposed for vector second-order Lipschitz nonlinear MASs. • The relationship between impulsive dynamical consensus and impulsive static consensus is analyzed. • A convex framework is proposed to design impulsive consensus gain matrices with guaranteed convergence rate. [ABSTRACT FROM AUTHOR]

• The transverse diameter of high-grade ccRCC tumors was larger. • The attenuation of high-grade ccRCC tumors in the un-contrast phase was higher. • The NIC in the nephrographic phase of high-grade ccRCC tumors was lower. • The multivariable model based on DL-CT could predict the WHO/ISUP grade of ccRCC. To evaluate whether the dual-layer spectral computed tomography urography (DL-CTU) images could predict WHO/ISUP pathological grading of clear cell renal cell carcinoma (ccRCC). We retrospectively included patients (n = 50) with pathologically confirmed ccRCC who underwent preoperative DL-CTU (from October 2017 to February 2021). They were divided into low-grade (WHO/ISUP 1/2, n = 30) and high-grade groups (WHO/ISUP 3/4, n = 20). The lesion size, attenuation (HU), iodine concentration (IC), normalized IC(NIC), and other quantitative characteristics were compared between the two groups. HU, IC, and NIC were obtained by plotting ROI with two different methods (circular ROI in the solid component or irregular ROI along the tumor edge containing tumor necrotic components). Receiver operating characteristic curves and multivariable model were used to evaluate the ability of parameters to predict WHO/ISUP grade. Transverse diameter (TD) of low-grade tumors was smaller, and HU in the non-contrast phase of the second method (HU-U-2) was lower than that of high-grade tumors (34.21±15.14 mm vs. 46.50 ± 20.68 mm, 27.33 ± 6.65 HU vs. 31.36 ± 6.09 HU, p < 0.05). The NIC in the nephrographic phase by the two methods (NIC-N-1 and NIC-N-2) of low-grade was higher than that of the high-grade group (0.78± 0.19 vs.0.58 ± 0.22, 0.73 ± 0.42 vs. 0.46 ± 0.22, p < 0.05). The final multivariable model composed of TD, HU-U-2, and NIC-N-1 could predict ccRCC grade with the area under the curve, sensitivity, specificity, and accuracy of 0.852, 70%, 90%, and 82%. Quantitative indicators in DL-CTU images could help predict the WHO/ISUP grade of ccRCC. [ABSTRACT FROM AUTHOR]

Lead-free Dielectric capacitors that possess high power density as well as swift charging/discharging speed are in tremendous requirement in pulse/high power fields, but the lower recovery energy density and efficiency restrict their applications. Herein, via triple collaborative optimization, we designed Nd-modified AgNbO 3 antiferroelectric ceramics with excellent energy storage performance. First, Nd3+ ions are smaller than Ag+ ions, which effectively inhibits cation displacements and the tilting of oxygen octahedra, leading to an optimized phase composition, the suppressed ferroelectricity and enhanced antiferroelectricity. Second, the valence of Nd3+ ions are higher than that of Ag+ ions, which help to lower the content of oxygen vacancies. Third, the random substitution of Nd3+, extrinsic ions, cause the chemical disorder, thus dwindling the grain size. Both of the latter could boost the breakdown field. Eventually, the synchronously boosted energy density of 7.16 J/cm3 and efficiency of 72 %, together with excellent frequency stability, temperature tolerance, ultrafast charging/discharging time of 45 ns and superhigh power density of 354.2 MW/cm3, are achieved in Ag 0.91 Nd 0.03 NbO 3. All these merits manifest Nd- AgNbO 3 as a promising candidate for lead-free high-power energy storage devices. Our work brings forward a good reference for developing the capabilities of antiferroelectric capacitors. [Display omitted] • Energy storage performance of AgNbO 3 ceramic is remarkably improved by Nb doping. • Ultrahigh W rec of 7.16 J/cm3 and considerably high η of 72 % are simultaneously realized. • Frequency stability <±4 %, thermal tolerance over 25–130 °C, P d >354.2 MW/cm3, and t 0.9 <45 ns are achieved. • This paper presents a triple collaborative optimization scheme for the design of advanced pulse/high power systems. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To explore the value of an artificial intelligence (AI)-based application for identifying plaque-specific stenosis and obstructive coronary artery disease from monoenergetic spectral reconstructions on coronary computed tomography angiography (CTA).Materials and Methods: This retrospective study enrolled 71 consecutive patients (52 men, 19 women; 63.3 ± 10.7 years) who underwent coronary CTA and invasive coronary angiography for diagnosing coronary artery disease. The conventional 120 kVp images and eight different virtual monoenergetic images (VMIs) (from 40 keV to 140 keV at increment of 10 keV) were reconstructed. An AI system automatically detected plaques from the conventional 120 kVp images and VMIs and calculated the degree of stenosis, which was further compared to invasive coronary angiography. The assessment was performed at a segment, vessel, and patient level.Results: Vessel and segment-based analyses showed comparable diagnostic performance between conventional CTA images and VMIs from 50 keV to 90 keV. For vessel-based analysis, the sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of conventional CTA were 74.3% (95% CI: 64.9%-82.0%), 85.6% (95% CI: 77.0%-91.4%), 84.3% (95% CI: 75.2%-90.7%), 76.1% (95% CI: 67.1%-83.3%) and 79.8% (95% CI: 73.7%-84.9%), respectively; the average sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy values of the VMIs ranging from 50 keV to 90 keV were 71.6%, 90.7%, 87.5%, 64.1% and 81.6%, respectively. For plaque-based assessment, diagnostic performance of the average VMIs ranging from 50 keV to 100 keV showed no significant statistical difference in diagnostic accuracy compared to those of conventional CTA images in detecting calcified (91.4% vs. 93.8%, p > 0.05), noncalcified (92.6% vs. 85.2%, p > 0.05) or mixed (80.2% vs. 81.2%, p > 0.05) stenosis, although the specificity was slightly higher (53.4% vs. 40.0%, p > 0.05) in detecting stenosis caused by mixed plaques. For VMIs above 100 keV, the diagnostic accuracy dropped significantly.Conclusion: Our study showed that the performance of an AI-based application employed to detect significant coronary stenosis in virtual monoenergetic reconstructions ranging from 50 keV to 90 keV was comparable to conventional 120 kVp reconstructions. [ABSTRACT FROM AUTHOR]

In this paper, the network-based observation and stabilization problems for Lipschitz nonlinear systems under scheduling communication are investigated. It is assumed that the signal transmission between the sensors and the controller or between the controller and the plant is implemented through a wireless network. Moreover, the scheduling of the sensed signal towards the controller is ruled by the Round-Robin (RR) protocol or the i.i.d. stochastic protocol. A general framework for observer-based feedback stabilization is proposed in which the control input is generated by a zero-order device which stores the sampled output of the sample-and-hold Luenberger observer-based controller. The resulting closed-loop system is modeled as a cascaded hybrid system with partial state subject to impulsive perturbation. Sufficient conditions for the existence of sample-and-hold Luenberger observer-based sampled-data controllers are derived by applying separation principle and time-dependent Lyapunov functionals. These conditions allow to design observers and controllers separately. A numerical example is presented to illustrate the effectiveness of the developed methodology. [ABSTRACT FROM AUTHOR]

Abstract This paper presents improved criteria for global exponential stability of reaction–diffusion neural networks with time-varying delays. A novel diffusion-dependent Lyapunov functional, which is directly linked to the diffusion terms, is suggested to analyze the role of diffusivity of each neuron on the model dynamics. In the case of Dirichlet boundary conditions, the extended Wirtinger’s inequality is employed to exploit the stabilizing effect of reaction–diffusion terms. In the framework of descriptor system approach, the augmented Lyapunov functional technique is utilized to reduce the conservatism in the values of the time delay bounds. As a result, the derived global stability criteria are more effective than the existing ones. Three numerical examples are provided to illustrate the effectiveness of the proposed methodology. [ABSTRACT FROM AUTHOR]

Polycrystalline (K 0.48 Na 0.52 ) 0.95 Li 0.05 (Nb 0.95 Sb 0.05 ) 1- x Fe x O 3 (0 ≤  x  ≤ 0.030) ceramics are synthesized by the conventional solid state reaction method. The samples with 0.010 ≤  x ≤  0.030 are found to possess good ferroelectricity, weak ferromagnetism and large magnetodielectric effect simultaneously at room temperature. Temperature dependence of magnetization and dielectric properties show that there are both magnetic and magnetodielectric anomalies in the vicinity of the ferroelectric rhombohedral-orthorhombic ( T R-O ) and orthorhombic-tetragonal ( T O-T ) phase transition temperatures. Furthermore, magnetodielectric effect as large as 16% is observed at 0.9 T near T R-O when x =  0.030. According to these results, a strong spin-lattice coupling is considered to exist in these samples. In the structure transition process, the spin interactions between Fe ions will alter for the severe distortion of the FeO 6 octahedron. Moreover, since there are more possible polarization vectors due to polymorphic phase transition (PPT), the local polarization of FeO 6 will also be greatly affected when the external magnetic field changes the spin interactions. [ABSTRACT FROM AUTHOR]

This paper proposes an event-triggered control framework, called dual-stage periodic event-triggered control (DSPETC), which unifies periodic event-triggered control (PETC) and switching event-triggered control (SETC). Specifically, two period parameters h 1 and h 2 are introduced to characterize the new event-triggering rule, where h 1 denotes the sampling period, while h 2 denotes the monitoring period. By choosing some specified values of h 2 , the proposed control scheme can reduce to PETC or SETC scheme. In the DSPETC framework, the controlled system is represented as a switched system model and its stability is analyzed via a switching-time-dependent Lyapunov functional. Both the cases with/without network-induced delays are investigated. Simulation and experimental results show that the DSPETC scheme is superior to the PETC scheme and the SETC scheme. [ABSTRACT FROM AUTHOR]

This paper describes the development and validation of a method to accurately identify snow/ice cover, surface melting, land surface and open water in polar regions using polar-orbiting Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) lidar measurements from the Cloud and Aerosol Lidar and Infrared Pathfinder Observation (CALIPSO) mission. The technique is based on the relationship between integrated attenuated backscatter color ratio and integrated depolarization ratio, and is proven to efficiently separate snow/ice cover and surface melting from open water and land surfaces. The method has been applied to 10 years (2006–2016) of CALIOP data to study the seasonal and inter-annual variability of Arctic sea ice cover and its declining trend. Results show that the area fraction of snow cover over land at latitudes > 60°N varied between 0.9 during winter and 0.1 in summer. The CALIOP observations of Arctic sea ice cover exhibit a strong seasonal cycle and significant inter-annual variability, which are consistent with the passive microwave-based sea ice results. The > 10 years of CALIOP continuous observations of the snow/ice cover will benefit the communities modeling snow/ice melting and climate change. [ABSTRACT FROM AUTHOR]

There is increasing evidence that the human lissencephaly-1 gene, LIS1 , plays an important role in carcinogenesis of several malignancies including leukemia. However, little is known about the relationship between single nucleotide polymorphisms (SNPs) in LIS1 and the susceptibility to myeloid leukemia. In the present study, we systematically screened 5 potentially functional polymorphisms in LIS1 , and conducted a case-control study including 660 acute myeloid leukemia (AML) patients and 1034 cancer-free controls in a Chinese population, to assess the association between these SNPs and AML risk. We found that the variant alleles of rs4790348, rs4790353, and rs7209748 could significantly increase the AML risk (rs4790348: adjusted OR = 1.31, 95%CI = 1.13–1.53 in additive model; rs4790353: adjusted OR = 4.97, 95%CI = 1.59–15.50 in recessive model; rs7209748: adjusted OR = 2.34, 95%CI = 1.11–4.94 in recessive model). These findings indicated that genetic variants in LIS1 may contribute to AML risk in Chinese population. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: The study aimed to assess the relationship between tumor marker index (TMI) and high-resolution computed tomography features in early-stage lung adenocarcinoma.Materials and Methods: Seventy-four stage IA lung adenocarcinomas confirmed pathologically were retrospectively evaluated. Lung nodules were divided into two types: solid nodule (SN) and subsolid nodule (SSN). The maximum diameters on mediastinal window in axial imaging (Dm) and tumor shadow disappearance rate (TDR) were measured. Meanwhile, other computed tomography features of lung nodules were also recorded. TMI represents the geometric mean of normalized CEA and CYFRA 21-1 values, and the discriminatory value of TMI in this study was set at 1.0. The evaluation of discriminatory values for Dm and the TMI between SNs and SSNs was done with Mann-Whitney U-test. The relationship between TDR and TMI in SSNs was evaluated by Pearson correlation analysis.Results: Of 74 cases, 40 cases (54.05%) showed SNs and 34 cases (45.95%) showed SSNs. Dm and TMI were higher in SNs than in SSNs (z = -4.782, P < 0.001; z = -2.647, P = 0.008). TDR demonstrated negative relationship with TMI in SSNs (r = -0.448, P = 0.008). Spiculation (odds ratio [OR] = 14.685; 95% confidence interval [CI]: 2.739-78.729; P = 0.002), nodule type (OR = 6.215; 95% CI: 1.531-25.228; P = 0.011), and gender (OR = 0.227; 95% CI: 0.062-0.833; P = 0.025) were independent factors associated with TMI.Conclusions: Early-stage lung adenocarcinoma with lower TDR coexisting with spiculation was associated with higher TMI, especially in patients with solid nodule, which tended to have poor prognosis. [ABSTRACT FROM AUTHOR]