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Adopting a healthy lifestyle during childhood could improve physical and mental health outcomes in adulthood and reduce relevant disease burdens. However, the lifestyles of children with mental, behavioral, and developmental disorders (MBDDs) remains under-described within the literature of public health field. This study aimed to examine adherence to 24-hour movement guidelines among children with MBDDs compared to population norms and whether these differences are affected by demographic characteristics.Data were from the 2016-2020 National Survey of Children's Health-a national, population-based, cross-sectional study. We used the data of 119,406 children aged 6 to 17 years, which included 38,571 participants with at least 1 MBDD and 80,835 without. Adherence to the 24-hour movement guidelines was measured using parent-reported physical activity, screen time, and sleep duration.Among children with MBDDs, 20.3%, 37.0%, 60.7%, and 77.3% met the physical activity, screen time, sleep, and at least 1 of the 24-hour movement guidelines. These rates were lower than those in children without MBDDs (22.8%, 46.2%, 66.7%, and 83.4%, respectively; all p values0.001). Children with MBDDs were less likely to meet these guidelines (odds ratio (OR) = 1.21, 95% confidence interval (95%CI): 1.13-1.30; OR = 1.37, 95%CI: 1.29-1.45; OR = 1.29, 95%CI: 1.21-1.37; OR = 1.45, 95%CI: 1.35-1.56) than children without MBDDs. Children with emotional disorders had the highest odds of not meeting these guidelines (OR = 1.43, 95%CI: 1.29-1.57; OR = 1.48, 95%CI: 1.37-1.60; OR = 1.49, 95%CI: 1.39-1.61; OR = 1.72, 95%CI: 1.57-1.88) in comparison to children with other MBDDs. Among children aged 12-17 years, the difference in proportion of meeting physical activity and screen time guidelines for children with versus children without MBDD was larger than that among children aged 6-11 years. Furthermore, the above difference of meeting physical activity guidelines in ethnic minority children was smaller than that in white children.Children with MBDDs were less likely to meet individual or combined 24-hour movement guidelines than children without MBDDs. In educational and clinical settings, the primary focus should be on increasing physical activity and limiting screen time in children aged 12-17 years who have MBDDs; and specifically for white children who have MBDDs, increasing physical activity may help.

A new ternary Mg1.4Co21.6B6 compound in the Mg-Co-B system was synthesized via a conventional solid-state reaction method and the effect of Ni-substitution on its crystal structure, thermal stability, solid solubility and physical properties were systematically investigated. The crystal structure of the Mg1.4Co21.6B6 compound was fully determined by the X-ray diffraction technique with Rietveld refinement method. It is found that Mg1.4Co21.6B6 crystallizes in the form of C6Cr23 structure type (space group: Fm-3m (No.225), a = 10.556(1)A, Z = 4). The results showed that the 4a sites have been occupied completely by Co atoms in present compound which with M2-xNi21+xB6 form belonging to the W2Cr21C6-type. When Mg1.4Co21.6B6 is repeatedly sintered at elevated temperatures, it becomes unstable and decomposes into Co3B and Mg. The lattice parameters of the Mg1.4Co21.6B6 solid solution alters dramtically with increasing Ni substitution, with no regular trend being observed. The electrical and magnetic performances of the 3.6Mg:3Co:17Ni:6B and 3.6Mg:3Co:18Ni:6B (nominal compositions) samples suggest that both samples are typical ferromagnetic materials. The temperature in the maximum drop of the ρ(T) curve decreases as a function of the Ni content. Base on the correlation between the critical temperature and Ni content, a linear fitting equation is obtained and the critical temperature of Mg1.4Co21.6B6 calculated utilizing the linear fitting equation. The findings in this work may provide certain reference values for material science on electrical magnetic properties and other references for researching the material further.

Aero-engine turbine blades may suffer overheating during service, which can result in severe microstructural and mechanical degradation within tens of seconds. In this study, the thermal cycling creep under (950°C/15 min+1100°C/1 min)-100 MPa was performed on a directionally solidified superalloy, DZ125. The effects of overheating and thermal cycling on the creep properties were evaluated in terms of creep behavior and microstructural evolution against isothermally crept specimens under 950°C/100 MPa, 950°C/270 MPa, and 1100°C/100 MPa. The results indicated that the thermal cycling creep life was reduced dramatically compared to the isothermal creep under 950°C/100 MPa. The plastic creep deformation mainly occurred during the overheating stage during the thermal cycling creep. The thermal cycling creep curve exhibited three stages, similar to the 1100°C isothermal creep, but its minimum creep rate occurred at a lower creep strain. The overheating events caused severe microstructural degradation, such as substantial dissolution of γ' phase, earlier formation of rafted γ' microstructure, widening of the γ channels, and instability of the interfacial dislocation networks. This microstructural degradation was the main reason for the dramatic decrease in thermal cycling creep life, as the thermal cycling promoted more dislocations to cut into γ' phase and more cracks to initiate at grain boundaries, carbides, and residual eutectic pools. This study underlines the importance of evaluating the thermal cycling creep properties of superalloys to be used as turbine blades and provides insights into the effect of thermal cycling on directionally solidified superalloys for component design.

The fault propagation of multistate systems (MSSs) with various operational modes is a critical factor affecting the reliability and safety of systems. However, traditional methods have difficulty describing the influence of function transitions and multiple faults of components on fault propagation, and are inapplicable for accurately evaluating the dynamic reliability of MSSs. To solve these issues, an agent-based method is developed to evaluate the dynamic reliability of MSSs. This study proposes a reliability modeling framework that consists of a management agent and several system agents. Combined with different agents, two types of models are established to describe the logical relationships among components. Moreover, Monte Carlo simulation is used to evaluate the dynamic reliability of MSSs, and a visual failure paths analysis method is proposed to inhibit potential risk. The LH4-1 horizontal Christmas tree is used to verify the effectiveness of proposed method. Under the designed working condition, the dynamic reliability curve of system with three operational modes and the visual failure paths including 15-node are obtained. By comparing the influence of failure rates, it is found that the production choke valve, flowlines, tree cap and MEG chemical control valve have a great impact on the system reliability.

This paper develops a novel optimization method oriented to the resilience of multiple Unmanned Aerial Vehicle (multi-UAV) formations to achieve rapid and accurate reconfiguration under random attacks. First, a resilience metric is applied to reflect the effect and rapidity of multi-UAV formation resisting random attacks. Second, an optimization model based on a parameter optimization problem to maximize the system resilience is established. Third, an Adaptive Learning-based Pigeon-Inspired Optimization (ALPIO) algorithm is designed to optimize the resilience value. Finally, typical formation topologies with six UAVs are investigated as a case study to verify the proposed approach. The experimental results indicate that the proposed scheme can achieve resilience optimization for a multi-UAV formation reconfiguration by increasing the system resilience values to 97.53% and 81.4% after random attacks.

In this study, a novel safety integrity level (SIL) determination methodology of safety instrumented systems (SISs) with parameter uncertainty is proposed by combining multistage dynamic Bayesian networks (DBNs) and Monte Carlo simulation. A multistage DBN model for SIL determination with multiple redundant cells is established. The models of function inspection test interval and function inspection test stages are alternately connected to form the multistage DBNs. The redundant cells can have different M out of N voting system architectures. An automatic modeling of conditional probability between nodes is developed. The SIL determination of SISs with parameter uncertainty is constructed by using the multistage DBNs and Monte Carlo simulation. A high-pressure SIS in the export of oil wellplatform is adopted to demonstrate the application of the proposed approach. The SIL and availability of the SIS and its subsystems are obtained. The influence of single subsystem on the SIL and availability of the SIS is studied. The influence of single redundant element on the SIL and availability of the subsystem is analyzed. A user-friendly SIL determination software with parameter uncertainty is developed on MATLAB graphical user interface.

Most non-viral carriers for in vitro delivery of nucleic acids suffer from low efficiency of introducing mRNA and other nucleic acids, especially large mRNA. Cas9 protein is the nuclease part of the powerful gene-editing tool, CRISPR/Cas9 system, Cas9 mRNA is particularly large, thus presents a big challenge for delivery. We assembled a multilayered biodegradable nanocarrier to load Cas9 mRNA inside to protect Cas9 mRNA from degradation. We used a microfluidic chip to synthesize a small, positively charged, and degradable core to attract negatively charged Cas9 mRNA. The microfluidic assembly allows the core to be small enough to incorporate into a cationic liposome. The multilayered nanocarriers elevated the delivery efficiency of Cas9 mRNA by over 2 folds and increased the expression by over 5 folds compared to commercially used non-viral carriers. In addition, the multilayered nanocarriers do not require reduced serum medium for transfection. When using the standard complete medium for transfection, the multilayered nanocarriers could increase the expression of Cas9 mRNA by over 15 folds compared to commercially used non-viral carriers. The co-delivery of Cas9 mRNA and sgRNA via LRC elevated the gene-editing efficiency by 3 folds compared to that via commercially used non-viral carriers. Based on the higher transfection efficiency of Cas9 mRNA/sgRNA than commercially used non-viral carriers, these multilayered nanocarriers may have a good prospect as efficient commercial delivery carriers for Cas9 mRNA/sgRNA and other nucleic acids.

In this study, thermal cycling creep tests under (950 °C/15 min+1100 °C/1 min)/100 MPa were performed to simulate the overheating service condition of a directionally solidified superalloy DZ125. The microstructural evolution and creep mechanism at each creep stage were revealed by systematic microstructure characterization after the interrupted creep tests. The results indicated that DZ125 superalloy exhibited three creep stages: the decelerating stage, the slow accelerating stage and the rapid accelerating stage. During creep, the un-recovered γ′ volume fraction at the lower temperature stages and the deterioration of grain boundary caused by the overheating stages were harmful to the creep resistance. During the decelerating stage, a few dislocations moved on the γ matrix. The rafted γ′ microstructure and dislocation networks formed near the minimum creep rate. Simultaneously, some dislocations sheared the γ′ phase as well. During the slow accelerating stage, the rafted γ′ microstructure and dislocation networks could prevent dislocations from moving. However, the dislocations shearing the γ′ phase, facilitated by the overheating and thermal cycling process, was conducive to creep deformation. During the rapid accelerating stage, more dislocations shearing the γ′ phase, severe γ′ phase degradation and increasing PFZs (precipitate free zones) along the grain boundary accelerated the creep deformation. The coupled effect of overheating and thermal cycling damage accelerated the deformation during the thermal cycling creep.

The alloying effects of Ni, W and Cr on the microstructural stability of CoNi-base alloys were investigated using a multicomponent diffusion multiple after being aged at 1000 °C for 1000 h. The diffusion multiple was carefully designed based on thermodynamic calculations. The relationships between alloy compositions and microstructural characteristics were established over a large compositional range using this single sample, and the alloying effects of Ni, W and Cr on the elemental partitioning behaviors between γ and γ′ two phases were thermodynamically analyzed using high-throughput calculation. The results together show that an increase of Ni content increases the γ′ volume faction in the long-term aged microstructures. However, the higher Ni content leads to the precipitation of the χ phase by promoting the partitioning of W from the γ′ phase to the γ phase. The decrease of W content dramatically reduces the γ′ volume faction, but the addition of Cr can properly counteract this effect by promoting the partitioning of Al and Ti from the γ phase to the γ′ phase. This study will be helpful for accelerating the development of novel γ′-strengthened multicomponent CoNi-base alloys, as well as providing experimental data to improve the thermodynamic database.

Deep cement mixed (DCM) soil columns have been widely utilized to improve soft soil to support embankments or seawalls. However, the influence of the time-dependent behavior of the soft soil on the performance of DCM column-supported embankments is not well understood. In this study, the finite element (FE) model was established to investigate the creep effects on settlements and load transfer mechanisms of the soft soil improved by DCM columns under embankment load. Comparisons were conducted for the cases of the soft soil with or without creep. The parametric analysis demonstrated that the area replacement ratio and Young's modulus of the DCM column can largely influence the long-term behaviors of the DCM column-improved composite ground. The numerical results were also compared with the results calculated by German design method (EBGEO) and British design method (BS 8006). Regarding the vertical stress taken by the DCM column, EBGEO method provides a lower limit while BS 8006 method provides an upper limit.

With the aim of understanding the effect of creep defects in the γ′ phase on the creep resistance, the atomic structure and elemental segregation behavior of stacking faults (SFs), three types of SF interactions and anti-phase boundaries (APBs) in a Co-Al-W-based single-crystal superalloy crept at 1000 °C/137 MPa up to 1.0% strain were investigated. Both superlattice intrinsic and extrinsic stacking faults (SISF and SESF) were observed in the γ′ precipitates, and the interactions of such faults had different configurations. Both V- and T-like configurations can be composed of SISF-SISF, SISF-SESF and SESF-SESF interactions, while the X-like configuration was only observed to be composed by SISF-SISF interaction. The strengthening effect and mechanism of such SF interactions on the creep resistance are discussed based on their density and formation mechanism. W elemental segregation was present along the SISFs and SESFs. In contrast, only the γ forming element Co was enriched near the leading partial dislocations (LPDs) of the SISFs/SESFs, stair-rod dislocations and APBs. The rate limiting step of the expansion of the SFs was estimated to be the drag effect induced by the Co diffusion. In addition, the local phase transformation from the L12 to A1 structure at the intersection of SFs was mainly attributed to the Co supersaturation and aided by wetting phenomenon from the APB.

A nano-scaled shuffle-induced modulated structure and heating-induced ordering have been characterized in a metastable β-titanium alloy, Ti-5Al-5Mo-5V-3Cr, and their inter-relationship was investigated through in-situ and ex-situ conventional and aberration-corrected scanning/transmission electron microscopy and atom probe tomography. The nano-scaled O′ phase with a disordered orthorhombic-modulated structure formed by the { 011 } 01 1 ¯ > β transverse phonon was characterized for the first time to be stable from room temperature to ∼200 °C. The O″ phase with an ordered orthorhombic structure formed from the β phase during aging above the O′ phase solvus temperature, where Al segregation in nano-scaled regions led to ordering of every third {011} planes.

The classical uncertainty principle plays an important role in quantum mechanics, signal processing and applied mathematics. With the development of novel signal processing methods, the research of the related uncertainty principles has gradually been one of the most hottest research topics in modern signal processing community. In this paper, the weighted Heisenberg–Pauli–Weyl uncertainty principles for the linear canonical transform (LCT) have been investigated in detail. Firstly, the Plancherel–Parseval–Rayleigh identities associated with the LCT are derived. Secondly, the weighted Heisenberg–Pauli–Weyl uncertainty principles in the LCT domain are investigated based on the derived identities. The signals that can achieve the lower bound of the uncertainty principle are also obtained. The classical Heisenberg uncertainty principles in the Fourier transform (FT) domain are shown to be special cases of our achieved results. Thirdly, examples are provided to show that our weighted Heisenberg–Pauli–Weyl uncertainty principles are sharper than those in the existing literature. Finally, applications of the derived results in time frequency resolution analysis and signal energy concentrations are also analyzed and discussed in detail.

Geosynthetics and deep cement mixed (DCM) soil columns have been widely used to improve soft soil grounds in many countries and regions. This paper presents an experimental study on a geosynthetic-reinforced sand fill over marine clay with or without DCM columns under different loadings. Two tests were conducted on the sand fill reinforced with fixed-end and free-end geosynthetics over marine clay under three-stage local loading to investigate the effects of the boundary conditions of geosynthetic reinforcement on reducing settlements. It is observed that the fixed-end geosynthetic sheet is more effective in reducing settlements than the free-end condition under identical local loading. Another test was conducted on the fixed-end geosynthetic-reinforced sand fill over the marine clay improved by DCM columns under single-stage uniform loading. The vertical stresses on the marine clay and on the DCM columns, as well as the tensile strains of the geosynthetic sheet in the overlying sand fill, were measured. The results revealed that the stress concentration ratio increases with an increase in consolidation settlements, and the maximum tensile strain of the geosynthetic sheet occurs near the edge rather than at the center of the top surface of the DCM columns. Keywords: Settlement, Geosynthetic, Reinforcement, Deep cement mixed soil columns