Shock-tube experiments are conducted to examine the initial-amplitude dependence of strong-shock-driven interfacial instability in reflected-shock configurations at Mach numbers ($M_s$) exceeding 3.0. Qualitative observations reveal a marked suppression (enhancement) of bubble (spike) growth under strong shocks, with stronger effects at higher dimensionless initial amplitudes ($ka_0$). The initial-amplitude effect on linear growth exhibits a non-monotonic dependence on $M_s$, contrary to the previously anticipated saturation behaviour, arising from the $M_s$ dependence of compressibility and vorticity-deposition contributions. Compressibility suppresses bubble growth via a shock-proximity mechanism while promoting spike evolution through a newly identified Mach-reflection mechanism, with their competition yielding a saturation dependence on $M_s$. In contrast, the effectiveness of vorticity deposition is modulated by the Mach-reflection structure, with reduced contributions at high $M_s$ due to geometric separation. Based on these insights, an empirical factor is proposed to quantify the initial-amplitude effect across a wide range of $ka_0$ and $M_s$. Dimensionless nonlinear amplitude evolution collapses across diverse $ka_0$ conditions. However, flow evolution depends strongly on $ka_0$, indicating that amplitude alone is insufficient to characterise the dynamics. Reliable prediction of nonlinear bubble (spike) evolution requires accurate representation of the shock-proximity and secondary-compression mechanisms (Mach-reflection and spike-acceleration mechanisms). However, existing nonlinear models fail to satisfy this requirement. The present study provides a foundation for future investigations of interfacial instability under extreme conditions relevant to inertial confinement fusion and astrophysical flows.

Dyslipidaemia is associated with chronic low-grade inflammation and immune dysfunction, but the immunological effects of dietary phytosterols in humans remain unclear. We conducted a secondary analysis of an outcome-assessor-blinded, randomised controlled feeding trial to evaluate the effects of a high-phytosterol (HPS) diet, using phytosterol-enriched corn–wheat germ blended oil (CWGO), compared with a low-phytosterol (LPS) diet using peanut oil, on systemic inflammatory markers, humoural immune markers and peripheral blood lymphocyte subsets in Chinese adults with dyslipidaemia. After a 2-week run-in period, 104 participants were randomised to the HPS group (n 52) or the LPS group (n 52) for 12 weeks. In intention-to-treat analyses, the HPS group had a higher CD4+:CD8+ ratio at 12 weeks than the LPS group (adjusted mean difference: 0·561; 95 % CI 0·060, 1·063; P = 0·03) and a lower CD8+ T-cell count (adjusted mean difference: −116·315 cells/μl; 95 % CI −215·781, –16·849; P = 0·02). No significant between-group differences were observed for systemic inflammatory markers, humoral immune markers or most other lymphocyte subset outcomes. In per-protocol analyses, the difference in CD4+:CD8+ ratio remained significant, whereas the reduction in CD8+ T-cell count was attenuated. These exploratory findings suggest that a 12-week phytosterol-enriched CWGO intervention may be associated with changes in T-cell subset balance in adults with dyslipidaemia, although the results should be interpreted cautiously given the exploratory nature of this secondary analysis.

An experimental investigation is conducted in a wind tunnel on a NACA0012 airfoil with a partially flexible polydimethylsiloxane membrane leeward surface extended from 16.7 % to 83.3 % of the chord length. Aerodynamic forces, membrane deformation and the surrounding flow field are measured simultaneously. The results show that membrane vibration effectively reduces the extent of the recirculation zone, thereby improving aerodynamic performance. Specifically, the stall angle is delayed by $3^\circ$, and the maximum lift coefficient is increased by 12.4 % compared with that of the rigid airfoil. Novel insights into the flow–structure interaction are established from both spatial and temporal perspectives. Spatially, comparisons across angles of attack reveal that membrane vibrations driven by strong pressure fluctuations near the trailing edge can propagate upstream, accompanied by modifications in the distribution of turbulent kinetic energy and enhanced flow mixing. Temporally, a detailed analysis of the strongly periodic membrane motion and unsteady flow structures near stall further demonstrates that the membrane dynamics is tightly coupled with the evolution of the leading-edge vortex. This coupling is associated with the modulation of coherent flow structures through periodic absorption and release of mechanical energy. Overall, the flexible membrane can provide effective flow control by reorganising the spatio-temporal distribution of energy within the flow via flow–structure interaction, without external energy input. The findings provide insights into potential low-energy flow-control strategies.

To address the limitation of maximum jump height constrained by the maximum torque of hip joint motors in bipedal wheeled robots during trajectory planning using the dual-mass linear spring model (DMLSM), this study aims to reduce the maximum required hip joint torque for achieving equivalent jump heights. Concurrently, reducing the maximum rotational speed of hip joint demanded by equivalent jumps is essential to minimize motor wear and enhance system stability. Building upon the dual-mass model, we propose a trajectory planning method based on hip joint motor state optimization (TPM-HJMSO). This method integrates a nonlinear spring model, cubic polynomial interpolation, and a min–max optimization approach with nonlinear constraints. Simulation results demonstrate two critical advances: TPM-HJMSO achieves 163.16% higher jump heights than the DMLSM under identical maximum hip torque constraints, while reducing maximum hip motor speed by 37.17% when attaining equivalent jump heights. These outcomes validate the method’s superior performance. Precise trajectory tracking is demonstrated through feedforward-plus-PD control in both Webots simulations and physical prototype experiments, verifying TPM-HJMSO’s effectiveness.

High-repetition-rate and high-stability short-pulse lasers have broad application prospects in large-scale integrated equipment serving industrial manufacturing and scientific research. Pulse compression techniques based on transient stimulated Brillouin scattering (SBS) are an effective means of obtaining short-pulse lasers. The transient effects and thermal breakdown enhancement effects in the high-repetition-rate transient SBS process will cause significant gain attenuation, resulting in a decrease in output energy reflectivity and stability. In this study, we proposed a pulse compression technique based on transient self-pumped Brillouin scattering (SPBS). By combining pump intensity attenuation with gain compensation based on a self-feedback seed model, the transmission loss and sound field intensity fluctuations during scattering were significantly reduced. The experiment verified the compression capability of the transient SPBS, which improved the output energy reflectivity and stability. The results showed that at a repetition rate of 300 Hz, the transient SPBS had a maximum energy reflectivity of 96.5% and an output energy of 24.1 mJ. Without the interference of the breakdown effect, a stable pulsed laser output with an energy relative standard deviation of only 1.42%, a time-domain duration of 225 ps and a peak power of over 100 MW was finally obtained. Our research provides a valuable reference for the generation of high-repetition-rate, high-peak-power lasers.

Multidimensional metabolic dysregulation is implicated in hypertension development, but the utility of comprehensive metabolic vulnerability indices for assessing hypertension risk associations remains unclear. This prospective cohort study analysed 150 591 participants from the United Kingdom Biobank. The metabolic vulnerability index and its components – inflammation vulnerability index (IVX) and metabolic malnutrition index (MMX) – were calculated from six metabolites (GlycA, small HDL particles, leucine, valine, isoleucine and citrate) measured by NMR spectroscopy. Cox proportional hazards models assessed associations with incident hypertension, adjusting for demographic, lifestyle and clinical factors. Restricted cubic spline analyses examined dose–response relationships, and subgroup analyses explored effect modifications by polygenic risk score, BMI and C-reactive protein levels. During follow-up, 32 198 participants developed hypertension. After comprehensive adjustment, IVX and metabolic vulnerability index (MVX) showed significant positive associations with hypertension risk (highest v. lowest quartile: hazard ratio (HR) = 1·25 (95 % CI: 1·20, 1·31) and HR = 1·19 (95 % CI: 1·15, 1·24), respectively, P < 0·001). Each standard deviation increase in IVX and MVX was associated with 9 % and 7 % higher hypertension risk, respectively. Conversely, MMX demonstrated a slight protective effect (HR = 0·96 (95 % CI: 0·92, 0·99), P = 0·016) and exhibited a U-shaped relationship with hypertension risk. Notably, associations between IVX/MVX and hypertension were significantly stronger in non-obese individuals (BMI < 30) compared with obese participants (BMI ≥ 30) (P-interaction < 0·001 and P = 0·007, respectively). Results remained robust in sensitivity analyses excluding extreme values and early hypertension cases. Metabolic vulnerability, particularly its inflammatory component, is independently associated with hypertension risk beyond traditional risk factors. These findings highlight the potential utility of comprehensive metabolomic profiling for early identification of individuals at elevated hypertension risk.

In this article, a new triple-loop recurrent neural network and observer-based two-stage fast terminal sliding mode controller (TRNNO-TFTSMC) is proposed for a quadrotor unmanned aerial vehicle (UAV) with nonlinear dynamics and external disturbances. The two-stage fast terminal sliding mode control scheme is designed to guarantee fast convergence of trajectory tracking within a finite time. In the architecture of the flight control system, the triple-loop recurrent neural network (TRNN) is designed to approximate the nonlinear dynamics, which include system uncertainties and known nominal terms. Furthermore, to mitigate the impact of external disturbances and the approximation error of TRNN on the performance of the control system, an observer is employed. Finally, the closed-loop stability of the quadrotor system is ensured based on Lyapunov theory, and the outperformance of the proposed flight control scheme is clearly demonstrated through a comparative study with other techniques.

We show a high-slope-efficiency Ho:CaYAlO4 laser using the conventional water-cooling method. Under an L-shaped laser resonator cavity with an overlapping efficiency greater than 98%, a maximum output power of 18.64 W at 2081 nm was achieved when the absorbed pump power was 26.83 W. By linear fitting, the slope efficiency relative to the absorbed pump power is 90.6%. Under the maximum output power, the beam quality factor is lower than 1.25 and the root-mean-square stability is about 0.42%. In addition, we validated the output performances of the laser in acousto-optic Q-switched mode under the high-slope-efficiency condition. At a pulse repetition rate of 10 kHz, the maximum average output power of 18.26 W and the narrowest pulse width of 40.1 ns were achieved, corresponding to a pulse energy, peak power and slope efficiency of 1.83 mJ, 45.54 kW and 87.7%, respectively. To the best of our knowledge, this laser may have the highest slope efficiency for a Ho-doped solid-state laser using conventional water-cooling.

This paper presents a novel UHF RFID tag antenna with metal-mount capability, broadband characteristics, and frequency controllability. To achieve anti-metal performance, we explore a vertical loop structure as the main radiator, with slots for frequency adjustment and layout flexibility. The antenna operates based on a hybrid magnetic–electric mode interaction mechanism, in which the vertical loop provides a magnetic-dipole-dominated radiation mode. Furthermore, asymmetric resonant dipole patches are loaded on both sides of the center feed line to introduce an auxiliary electric mode and broaden the operating bandwidth. This structural-level mode and coupling engineering enables independent control of the center frequency while maintaining wideband impedance matching. The proposed antenna has a compact size of $0.1951\lambda \times0.128\lambda \times0.0051 \lambda$, with the main radiation lobe concentrated within 60$^{\circ}$ from the zenith. By mounting on a $100\times100\times2\,\mathrm{mm}^{3}$ copper plate, it achieves a maximum read range of 7.32 m, which demonstrates the good adaptability for UHF RFID tagging on metal surfaces.

This study systematically investigated the effects of Lactiplantibacillus plantarum (Lp), cellulase (CE), and their combination (CELp) on the fermentation quality, fiber degradation, and microbial community in rapeseed straw silage. This research was carried out with a completely randomized design, and rapeseed straw was inoculated with L. plantarum (1.0 × 10⁶ colony-forming units [CFU]/g), CE (50,000 U/g), or CELp and fermented in vacuum-sealed bags at 25°C for 60 days. Results demonstrated that the CELp co-treatment yielded superior outcomes, significantly increasing lactic acid content, accelerating acidification, and effectively degrading neutral detergent fiber, acid detergent fiber, and hemicellulose compared to individual treatments. Microbial community analysis demonstrated that the CELp co-treatment effectively enriched functional bacterial treatments represented by Lactobacillus and Xanthomonas while significantly enhancing the activities of core enzymes, including L-lactate dehydrogenase, xylanase, and β-glucosidase. The CELp co-treatment intensified homolactic fermentation and structural carbohydrate decomposition, with correlation analysis revealing tight links among microbial composition, enzyme activities, and silage quality. In conclusion, the microbial–enzyme synergistic approach effectively improved the fermentation quality of rapeseed straw silage by directionally modulating the microbial community structure and enhancing core enzyme activities. These findings provide a novel theoretical basis for the efficient utilization of lignocellulosic agricultural by-products.

Richtmyer–Meshkov instability (RMI) at quasi-single-mode interfaces subjected to strong shocks with Mach number exceeding 3.0 is investigated through shock-tube experiments. To reveal the influence of higher-order initial modes, one single-mode and four quasi-single-mode interfaces with varying modal compositions are examined. The Richtmyer theory is experimentally verified for the first time to accurately capture the single-mode interface evolution from start-up to the linear stage. In contrast, it fails for quasi-single-mode scenarios, highlighting the significant effect of higher-order modes. By incorporating the influence of higher-order modes via linear superposition, a linear model for quasi-single-mode interface evolution is proposed, whose validation indicates negligible modal coupling in early evolution. For the nonlinear period, a representative model for weak-shock-driven RMI at a single-mode interface performs poorly, as it does not consider the influence of higher-order modes and key mechanisms such as shock proximity, secondary compression and spike acceleration. Based on the present findings, an empirical nonlinear model with favourable predictive capability is developed. Furthermore, by matching the new linear and nonlinear models, a complete description of the amplitude evolution of single-mode and quasi-single-mode interfaces from start-up to nonlinear stages is achieved, offering new insight into modelling strong-shock-driven RMI.

Objectives/Goals: Conventional magnetic resonance imaging (MRI) methods are unable to visualize bone comparable to computed tomography (CT). Radiation therapy can result in post-treatment complications, such as osteoradionecrosis (ORN). We aim to integrate black bone (BB) MRI into routine follow-up MRI scans as an alternative to CT to monitor the development of ORN. Methods/Study Population: We assess the CT, T2-weighted (T2W), and BB MRI scans of 21 head and neck cancer patients without active ORN. All images are acquired within 4 weeks of each other to minimize anatomical variability. The mandibles are manually segmented on each image, and the MR images are registered to the CT to map the CT contour onto the MR images for comparison. Image segmentation evaluation metrics, including dice similarity coefficient (DSC), mean distance to agreement (MDA), and Hausdorff distance (HD), assess for spatial differences between each MRI sequence, using CT as reference standard. DSC measures contour volume, while MDA and HD assess the differences in contour boundaries, with HD sensitive to outliers. We employ a Wilcoxon signed-rank test using a significance value of p≤0.05 to assess for statistical significance. Results/Anticipated Results: Using metrics widely accepted in biomedical research, we assess the performance of BB to visualize mandible against its conventional T2W MRI counterpart when compared to CT. Black bone has a significantly different DSC (median=0.878, IQR=0.0397) than T2W (median=0.806, IQR=0.0876; p<0.0001), indicating high volumetric overlap between contours on BB and CT. Black bone has a significantly different MDA (median=0.0731mm, IQR=0.0227mm) than T2W (median=0.119mm, IQR=0.0697; p<0.0001), indicating high agreement between contour boundaries on BB and CT. Black bone has a significantly different HD (median=0.649mm, IQR=0.211mm) than T2W (median=1.80, IQR=0.933; p<0.0001), indicating a submillimeter difference between contour boundaries, including outliers, on BB and CT. Discussion/Significance of Impact: Our results exhibit BB as a promising non-ionizing alternative to CT for bony visualization compared to conventional MRI. BB has potential to detect early anatomical changes in bone, providing a standardized assessment of ORN. This can improve our dose–response understanding of post-treatment toxicities, refining radiation treatment planning.

It is of great importance for fields such as implosion dynamics and fusion research to understand the dynamics of ejecta transport in converging gases. In this paper, the evolution of particulate flow within a cylindrically imploding system is investigated experimentally and numerically. The ejecta particles are emitted from the inner surface of a roughened Sn liner into vacuum, He and Ar gases. Dynamic images of liner implosion and ejecta transport are obtained with X-ray radiographs and multi-frame optical schlieren images. The transport of ejecta particles is simulated with a four-way coupled multiphase flow model, including modelling of gas–particle coupling and inter-particle collisions. Results reveal that the ejecta transport in shock-induced converging gases differs significantly from that in planar systems, primarily due to features such as interaction with the rebounding gas shock wave and continuous compression by the imploding liner. After being generated from the inner surface, the ejecta width undergoes an ‘expansion–compression’ variation. According to mechanisms governing ejecta–gas coupling, three distinct stages of ejecta evolution are identified: (i) post-shock transport dominated by drag and particle breakup; (ii) shock-particle interaction leading to quick reduction in particle size and rapid deceleration of the ejecta front; and (iii) dense ejecta compression governed by inter-particle collisions. Leveraging particle motion and size predictions at the ejecta front, combined with the self-similar converging shock solution, a theoretical model is established to estimate the three-stage evolution of ejecta width in a cylindrically converging system.

New-type metasedimentary rock-hosted stratiform Cu deposits occur in the Jianglang Dome. They are hosted by the Late Neoproterozoic Liwu Group and were unusually induced by an epigenetic magmatic-hydrothermal system. However, the source characteristics of fluids and metals remain poorly understood. Here, we employed Re-Os dating and He-Ar-S-Pb isotopes to determine their mineralization age and origin. Chalcopyrite Re-Os isotopic dating defines an isochron age of 162.7 ± 3.2 Ma and a crust-like initial 187Os/188Os ratio of 1.421 ± 0.021 (n = 4). Sulphide He-Ar isotope (n = 20) yields low R/Ra ratios of 0.052–0.144, high 40Ar/36Ar ratios of 479–2463 and low 40Ar*/4He ratios of 0.013–0.804, with calculated Hemantle values of 0.69–2.20 wt.%. In situ chalcopyrite sulphur isotope exhibits positive δ34SV-CDT values of 3.87–9.50‰ (n = 72). Together with similar lead isotope data of chalcopyrite separates (n = 40) and ca. 164 Ma granites (n = 4), as well as low residual gravity anomalies in this region, our integrated data indicate an epigenetic magmatic-hydrothermal mineralization at ca. 163 Ma. The ore-forming fluids were dominantly crust-derived, with minor air-saturated water and negligible mantle input (0.69–2.20 wt.%). This is most likely attributed to the low proportion (total <5 vol%) of sandwiched metabasic rocks in the metalliferous Liwu Group. All the investigated orebodies show source homogeneity, in contrast to classic sediment-hosted stratiform Cu deposits with isotopic heterogeneity. Further, our findings imply significant mineral exploration potential in the Jianglang Dome and analogous domes in the eastern Songpan-Ganze Orogen.

A novel fixed-time cooperative guidance law is developed to enable multiple flight vehicles to simultaneously intercept various target motions with desired impact angle, including stationary, constant-velocity moving and manoeuvring targets, with a unified guidance structure that requires no mode switching or target motion classification. First, a fixed-time distributed cooperative guidance law is developed using the theory of multi-intelligence cooperative control, which is formulated along the line of sight (LOS) direction. This approach ensures that the impact time is regulated, enabling multiple flight vehicles to intercept the target simultaneously within a fixed time. In the second phase, employing a sliding manifold and a fixed-time reaching law, the normal acceleration of each flight vehicle is designed to ensure that the LOS angle converges to its target value within a fixed duration. Unknown components of the target’s acceleration are estimated via fixed-time observers and incorporated into the guidance commands, enhancing precision and robustness in the guidance process. In conclusion, the proposed approach proves the effectiveness and superiority through numerical simulations, including various target motions, switching communication topology, robustness against uncertainties based on Monte Carlo experiment and comparative studies.

Birds extend their flight envelope and adapt to time-varying aerodynamic demands by actuating the shoulder and wrist joints to morph the local sweep angles of the inner and outer wings. However, the local sweep morphing may cause unfavourable unsteady lift on the lifting surface. We investigate these unsteady lift responses using an avian-inspired wing with local sweep morphing under different morphing strategies. The unsteady lift is computed through numerically solving the incompressible Navier–Stokes equations. The results show that the local sweep morphing wing experiences a substantial maximum lift overshoot when forward sweeping and a notable maximum lift undershoot when backward sweeping. These lift over/undershoot phenomena can be alleviated by three measures: adopting smooth nonlinear morphing kinematics, initiating morphing from lift extrema opposite to the over/undershoot direction and prolonging the morphing duration. For the lift over/undershoot, the component obtained by subtracting the extended pre-morphing lift is attributed to the modification induced by local sweep morphing. To predict such lift over/undershoot, we develop a reduced-order unsteady model for the sweeping-modification lift coefficient, where Prandtl’s lifting-line theory is extended to the regime of variable translational velocity. The proposed model captures the symmetry of the sweeping-modification lift coefficient, dominated by the horizontal morphing velocity. Additionally, the vertical morphing velocity is found to correlate with the asymmetry of the sweeping-modification lift coefficient by modulating the leading-edge vortices. This study is expected to improve the understanding of surging-wing flow physics and support the design of bio-inspired multifunctional aircraft.