We present an experimental study of proton acceleration driven by femtosecond multi-PW lasers of three different prepulse parameters with the peak laser intensity of 1.2 × 1021 W/cm2 irradiating micrometre-thick metal foils. For 4-μm-thick copper foils, the highest-energy proton beam of 58.9 MeV is generated with the moderate-contrast laser, while the low-contrast or high-contrast lasers result in the lower proton cutoff energies. The one-dimensional hydrodynamic and two-dimensional particle-in-cell simulations indicate that the front preplasma of foils induced by the laser prepulse can enhance electron acceleration and in turn improve proton acceleration, while the rear preplasma will weaken the sheath field and be unfavourable for accelerating ions. For the case of the moderate contrast, the scale length of the front preplasma is long enough to generate high-temperature electrons compared to the high-contrast case, and the scale length of the rear preplasma is so short that the sheath field still remains strong compared with the low-contrast case, which is advantageous for generating high-energy protons. Meanwhile, a concrete map is theoretically given for accelerating higher-energy protons. This work extends the concept of the prepulse effect on target normal sheath acceleration (TNSA) to a wider range of laser parameters (multi-PW, 1021 W/cm2), representing an important step towards potential applications of TNSA-driven proton sources, especially considering that PW and even 10 PW laser facilities exist all around the world.

We develop and test a theoretical model to investigate the effects of faultlines within the top management team (TMT) on corporate financial fraud. We propose that TMT faultlines can generate mutual monitoring among factional subgroups in the executive suite, which reduces fraudulent behavior. We also examine the contingent roles of subgroup configuration and the TMT members’ tenure overlap in shaping the relationship between TMT faultlines and financial fraud. The mutual monitoring effect is likely to be stronger when the TMT has a balanced subgroup configuration and shorter TMT members’ tenure overlap. We test our argument in the context of publicly listed firms in China. This article extends the mutual monitoring perspective of corporate governance and has important research implications for the corporate financial fraud literature.

We examine how ambient temperature $T$ (23–90 $^\circ \mathrm{C}$) alters the dynamics of spark-induced cavitation bubbles across a range of discharge energies. As $T$ rises, the collapse of an isolated spherical bubble weakens monotonically, as quantified by the Rayleigh collapse factor, minimum volume and maximum collapse velocity. When the bubble is generated near a rigid wall, the same thermal attenuation is reflected in reduced jet speed and diminished migration. Most notably, at $T \gtrsim 70\,^\circ \text{C}$, we observe a previously unreported phenomenon: secondary cavitation nuclei appear adjacent to the primary bubble interface where the local pressure falls below the Blake threshold. The pressure reduction is produced by the over-expansion of the primary bubble itself, not by rarefaction waves as suggested in earlier work. Coalescence between these secondary nuclei and the parent bubble seeds pronounced surface wrinkles that intensify Rayleigh–Taylor instability and promote fission, providing an additional route for collapse strength attenuation. These findings clarify the inception mechanism of high-temperature cavitation and offer physical insight into erosion mitigation in heated liquids.

Non-spherical bubble collapses near solid boundaries, generating water hammer pressures and shock waves, were recognized as key mechanisms for cavitation erosion. However, there is no agreement on local erosion patterns, and cavitation erosion damage lacks quantitative analysis. In our experiments, five distinct local erosion patterns were identified on aluminium sample surfaces, resulting from the collapse of laser-induced cavitation bubbles at moderate stand-off distances of $0.4\leqslant \gamma \leqslant 2.2$, namely bipolar, monopolar, annular, solar-halo and central. Among them, the bipolar and monopolar patterns exhibit the most severe cavitation erosion when the toroidal bubbles undergo asymmetrical collapse along the circumferential direction during the second cycle. Shadowgraphy visualization revealed that asymmetrical collapse caused shockwave focusing through head-on collision and oblique superposition of wavefronts. This led to the variations in toroidal bubble radii and the positions of maximum erosion depth not matching at certain stand-off distances. Both initial plasma asymmetry and bubble–wall stand-off distance were critical in determining circumferential asymmetrical collapse behaviours. At large initial aspect ratios, the elliptical jet tips form during the contraction process, resulting in the toroidal bubble collapsing from regions with smaller curvature radii, ultimately converging to the colliding point along the circumferential direction. Our three-dimensional simulations using OpenFOAM successfully reproduce the key features of circumferentially asymmetrical bubble collapse. This study provides new insights into the non-spherical near-wall bubble collapse dynamics and provides a foundation for developing predictive models for cavitation erosion.

Most twin registries have not systematically collected the data required to determine gender identity, which has limited opportunities to evaluate potential familial contributors to gender diversity. This study addresses this gap by analyzing responses to gender identity questions introduced in Twins Research Australia’s 2023 survey. Among 4475 respondents (mean age 52.2 years, SD = 15.3), 36 (0.8%) indicated a transgender or gender diverse identity, which is consistent with population-based estimates of gender diversity internationally. Gender diversity co-occurred in 2/19 monozygotic pairs and 0/8 dizygotic pairs, giving rise to tetrachoric correlations of 0.62 (95% CI [0.33, 0.87]) and 0.00 (95% CI [0.00, 0.88]), respectively. These results broadly align with previous concordance estimates from twin studies that were specifically focused on gender identity. Although limited by a small sample size, these findings demonstrate the feasibility and utility of systematically collecting gender identity data through routine twin registry surveys.

An advanced deformable Kirkpatrick–Baez (K-B) mirror system was developed, equipped with high-speed piezoelectric actuators, and designed to induce beam decoherence and significantly enhance the quality of X-ray imaging by minimizing undesirable speckles in synchrotron radiation or free-electron laser facilities. Each individual mirror is engineered with 36 independent piezoelectric actuators that operate in a randomized manner, orchestrating the mirror surface to oscillate at a high frequency up to 100 kHz. Through in situ imaging single-slit diffraction measurement, it has been demonstrated that this high-frequency-vibration mirror system is pivotal in disrupting the coherent nature, thereby diminishing speckle formation. The impact of the K-B mirror system is profound, with the capability to reduce the image contrast to as low as 0.04, signifying a substantial reduction in speckle visibility. Moreover, the coherence of the X-ray beam is significantly lowered from an initial value exceeding 80% to 13%.

The collapse of an initially spherical cavitation bubble near a free surface leads to the formation of two jets: a downward jet into the liquid, and an upward jet penetrating the free surface. In this study, we examine the surprising interaction of a bubble trapped in a stable cavitating vortex ring approaching a free surface. As a result, a single fast and tall liquid jet forms. We find that this jet is observed only above critical Froude numbers ($Fr$) and Weber numbers ($We$) when ${Fr}^2 (1.6-2.73/{We}) > 1$, illustrating the importance of inertia, gravity and surface tension in accelerating this novel jet and thereby reaching heights several hundred times the radius of the vortex ring. Our experimental results are supported by numerical simulations, revealing that the underlying mechanism driving the vortex ring acceleration is the disruption of the equilibrium of high-pressure regions at the front and rear of the vortex ring caused by the free surface. Quantitative analysis based on the energy relationships elucidates that the velocity ratio between the maximum velocity of the free-surface jet and the translational velocity of the vortex ring is relatively stable yet is attenuated by surface tension when the jet is mild.

In this paper, we present and evaluate a novel Bayesian regime-switching zero-inflated multilevel Poisson (RS-ZIMLP) regression model for forecasting alcohol use dynamics. The model partitions individuals’ data into two phases, known as regimes, with: (1) a zero-inflation regime that is used to accommodate high instances of zeros (non-drinking) and (2) a multilevel Poisson regression regime in which variations in individuals’ log-transformed average rates of alcohol use are captured by means of an autoregressive process with exogenous predictors and a person-specific intercept. The times at which individuals are in each regime are unknown, but may be estimated from the data. We assume that the regime indicator follows a first-order Markov process as related to exogenous predictors of interest. The forecast performance of the proposed model was evaluated using a Monte Carlo simulation study and further demonstrated using substance use and spatial covariate data from the Colorado Online Twin Study (CoTwins). Results showed that the proposed model yielded better forecast performance compared to a baseline model which predicted all cases as non-drinking and a reduced ZIMLP model without the RS structure, as indicated by higher AUC (the area under the receiver operating characteristic (ROC) curve) scores, and lower mean absolute errors (MAEs) and root-mean-square errors (RMSEs). The improvements in forecast performance were even more pronounced when we limited the comparisons to participants who showed at least one instance of transition to drinking.

The environmental effects of nanoparticles have attracted widespread attention. The removal and recycling of nanoparticles are crucial for both environmental protection and resource reuse. However, current removal and recycling methods are not yet mature, and there is a need to explore inexpensive materials for the efficient removal and recycling of nanoparticles. This study investigates the effects of pyrite species, thermal modification temperature, pH and ionic strength on the adsorption of gold nanoparticles (AuNPs) by pyrite. The experimental results demonstrate that the adsorption rate of artificially thermally modified pyrite is slightly faster than that of naturally thermally modified pyrite. However, the concentration of Fe ions dissolved from the artificially thermally modified pyrite is higher. Natural pyrite, when thermally modified at 400°C and 500°C, adsorbs 100% of AuNPs within 10 min. The lower the acidity of the system, the faster the adsorption rate. Conversely, an increase in ionic strength decreases the adsorption rate. Artificially thermally modified pyrite primarily adsorbs AuNPs through electrostatic gravitational attraction, which is supplemented by a significant amount of chemisorption. After four recycling cycles, the adsorption and desorption rates of AuNPs using artificially thermally modified pyrite were 92.1% and 94.2%, respectively, indicating excellent adsorption and recovery performance. The results of this study provide a new method for the recycling of nanoparticles and an experimental basis for the further application of thermally modified pyrite in environmental treatments.

Feed intake, a critical factor for dairy cows during the postpartum period, is intricately linked to the rumen microbiome. However, the specific roles of rumen metagenome and metabolome in modulating feed intake in postpartum dairy cows remain unclear. In the current study, 20 postpartum dairy cows were divided into low feed intake (n = 5) and high feed intake (HFI, n = 5) groups to investigate the role of ruminal microbial composition, function, and metabolism on feed intake using a combined approach of metagenomics and metabolomics. Our analysis revealed a significant enrichment of Bacteroides and Fibrobacter in HFI cows (p < 0.05), contributing to enhanced protein and energy metabolism. Metabolomic analysis disclosed that HFI cows exhibited a higher relative concentration of rumen metabolites, such as alpha-tocopheryl acetate (fold change = 9.2, p = 0.008), linoleic acid (fold change = 5.96, p = 0.007), and leucine (fold change = 4.14, p = 0.004). Spearman correlation analysis pinpointed a positive correlation between specific microbiota (Succinivibrionaceae and Prevotellaceae) and metabolites involved in amino acid and peptide metabolism, fatty acid metabolism, and conjugates. Furthermore, co-occurrence network analysis showed that the unclassified_f_Succinivibrionaceae, Succinatimonas, and Ruminobacte were significantly associated with dry matter intake-associated metabotypes, including rumen metabolites involved in fatty acids and conjugates, favonoids, and gycerophosphocholines. The feed intake variation explained by the rumen microbiome, functions, and metabolites were 29.63%, 27.30%, and 33.50%, respectively. These findings provide comprehensive insights into rumen metagenomics at different feed intake levels in postpartum dairy cows, potentially guiding strategies to manipulate the rumen microbiome for feed intake and production improvement.

Er:CaF2 crystals are crucial gain media for producing 3 μm mid-infrared (MIR) lasers pumped by 976 nm continuous-wave (CW) lasers owing to their low phonon energy and high conversion efficiency. This study investigated the damage characteristics and mechanism of Er:CaF2 crystals irradiated with a 976 nm CW laser. The laser-induced damage threshold of Er:CaF2 crystals with different Er3+ doping levels was tested; the damage morphology consists of a series of regular 70° cracks related to the angle of the crystal slip system on the surface. A finite-element model was used to calculate the temperature and stress fields of the crystals. The results indicated that the damage can be attributed to surface tensile stresses caused by the temperature gradient, and crystals with higher doping concentrations were more susceptible to damage owing to stronger light absorption. These findings provide valuable insights into the development of high-power MIR lasers.

A novel theoretical model for bubble dynamics is established that simultaneously accounts for the liquid compressibility, phase transition, oscillation, migration, ambient flow field, etc. The bubble dynamics equations are presented in a unified and concise mathematical form, with clear physical meanings and extensibility. The bubble oscillation equation can be simplified to the Keller–Miksis equation by neglecting the effects of phase transition and bubble migration. The present theoretical model effectively captures the experimental results for bubbles generated in free fields, near free surfaces, adjacent to rigid walls, and in the vicinity of other bubbles. Based on the present theory, we explore the effect of the bubble content by changing the vapour proportion inside the cavitation bubble for an initial high-pressure bubble. It is found that the energy loss of the bubble shows a consistent increase with increasing Mach number and initial vapour proportion. However, the radiated pressure peak by the bubble at the collapse stage increases with decreasing Mach number and increasing vapour proportion. The energy analyses of the bubble reveal that the presence of vapour inside the bubble not only directly contributes to the energy loss of the bubble through phase transition but also intensifies the bubble collapse, which leads to greater radiation of energy into the surrounding flow field due to the fluid compressibility.

Human alveolar echinococcosis is a hard-to-treat and largely untreated parasitic disease with high associated health care costs. The current antiparasitic treatment for alveolar echinococcosis relies exclusively on albendazole, which does not act parasiticidally and can induce severe adverse effects. Alternative, and most importantly, improved treatment options are urgently required. A drug repurposing strategy identified the approved antimalarial pyronaridine as a promising candidate against Echinococcus multilocularis infections. Following a 30-day oral regimen (80 mg kg−1 day−1), pyronaridine achieved an excellent therapeutic outcome in a clinically relevant hepatic alveolar echinococcosis murine model, showing a significant reduction in both metacestode size (72.0%) and counts (85.2%) compared to unmedicated infected mice, which revealed significantly more potent anti-echinococcal potency than albendazole treatment at an equal dose (metacestode size: 42.3%; counts: 4.1%). The strong parasiticidal activity of pyronaridine was further confirmed by the destructive damage to metacestode tissues observed morphologically. In addition, a screening campaign combined with computational similarity searching against an approved drug library led to the identification of pirenzepine, a gastric acid-inhibiting drug, exhibiting potent parasiticidal activity against protoscoleces and in vitro cultured small cysts, which warranted further in vivo investigation as a promising anti-echinococcal lead compound. Pyronaridine has a known drug profile and a long track record of safety, and its repurposing could translate rapidly to clinical use for human patients with alveolar echinococcosis as an alternative or salvage treatment.

The Indo-Pacific Warm Pool (IPWP) significantly influences the global hydrological cycle through its impact on atmospheric-oceanic circulation. However, gaining a comprehensive understanding of the hydrologic climate dynamics within the IPWP and its broader effects on the global climate have been hindered by spatial and temporal limitations in paleoclimate records on orbital timescales. In this study, we reconstructed precipitation records (approximated from δ18Osw-ivc) over the past 450 kyr, based on planktonic foraminiferal Mg/Ca and δ18O data obtained from International Ocean Discovery Program Site U1486 in the western tropical Pacific. The δ18Osw-ivc record revealed a generally consistent pattern with precession variations over the past 450 kyr, closely corresponding to changes in boreal summer insolation at the equator. The δ18Osw-ivc record displayed an anti-phased relationship with Chinese speleothem δ18O records on the precession band, with lower precipitation in the western tropical Pacific and higher precipitation in the East Asia summer monsoon region during periods of high Northern Hemisphere summer insolation. This anti-phased correlation primarily resulted from the north-south migration of the Intertropical Convergence Zone (ITCZ), influenced by the interhemispheric insolation contrast. By considering additional δ18Osw-ivc records from various locations within the IPWP region, we identified synchronous precipitation changes within the IPWP on the precession band. The synchronization of precipitation on both margins of the ITCZ’s seasonal range and differences between central and marginal regions of the ITCZ within the IPWP revealed the expansion and contraction of the ITCZ on precession band.

In this paper, we present a theoretical, experimental and numerical study of the dynamics of cavitation bubbles inside a droplet suspended in another host fluid. On the theoretical side, we provided a modified Rayleigh collapse time and natural frequency for spherical bubbles in our particular context, characterized by the density ratio between the two liquids and the bubble-to-droplet size ratio. Regarding the experimental aspect, experiments were carried out for laser-induced cavitation bubbles inside oil-in-water (O/W) or water-in-oil (W/O) droplets. Two distinct fluid-mixing mechanisms were unveiled in the two systems, respectively. In the case of O/W droplets, a liquid jet emerges around the end of the bubble collapse phase, effectively penetrating the droplet interface. We offer a detailed analysis of the criteria governing jet penetration, involving the standoff parameter and impact velocity of the bubble jet on the droplet surface. Conversely, in the scenario involving W/O droplets, the bubble traverses the droplet interior, inducing global motion and eventually leading to droplet pinch-off when the local Weber number exceeds a critical value. This phenomenon is elucidated through the equilibrium between interfacial and kinetic energies. Lastly, our boundary integral model faithfully reproduces the essential physics of the non-spherical bubble dynamics observed in the experiments. We conduct a parametric study spanning a wide parameter space to investigate bubble–droplet interactions. The insights from this study could serve as a valuable reference for practical applications in the field of ultrasonic emulsification, pharmacy, etc.

Knowledge of clay mineralogy is essential for understanding the source areas and weathering environments of fluvial sediments, particularly in large reservoirs facing serious problems with sediment deposition, such as the Three Gorges Reservoir (TGR) in east-central China. The purpose of the present study was to identify the sediment provenances and weathering regimes contributing to the sediment load in the TGR by determining the clay-mineral and geochemical compositions of surface sediments during various seasons. X-ray diffractometry and scanning electron microscopy (SEM) were used to identify the clay minerals. The results showed that illite was the dominant mineral, followed in order by kaolinite, chlorite, and montmorillonite. From a mineralogical perspective, distal sources were the main contributors to the TGR sediments, and regional sources (surrounding tributaries) also contributed much during the three seasons, while proximal sources (hillslope soils) supplied sediment in the flood season but not in the other two seasons. The geochemical and hydrological data generally supported the mineralogical results. In the flood season, the chemical indices of the TGR sediments were >0.4, showing that the sediments contained Al-rich illite minerals and experienced intense hydrolysis. In the other two seasons the TGR sediments were enriched in Fe- and Mg-rich illite minerals, resulting from strong physical weathering. Furthermore, precipitation, rather than air temperature or latitude, was the factor that controlled weathering intensity. These findings provide deep insights into the sediment cycle and chemical weathering in this large reservoir basin.

The laboratory generation and diagnosis of uniform near-critical-density (NCD) plasmas play critical roles in various studies and applications, such as fusion science, high energy density physics, astrophysics as well as relativistic electron beam generation. Here we successfully generated the quasistatic NCD plasma sample by heating a low-density tri-cellulose acetate (TCA) foam with the high-power-laser-driven hohlraum radiation. The temperature of the hohlraum is determined to be 20 eV by analyzing the spectra obtained with the transmission grating spectrometer. The single-order diffraction grating was employed to eliminate the high-order disturbance. The temperature of the heated foam is determined to be T = 16.8 ± 1.1 eV by analyzing the high-resolution spectra obtained with a flat-field grating spectrometer. The electron density of the heated foam is about $N_e=4.0\pm 0.3\times {10}^{20}{\text{cm}}^{-3}$ under the reasonable assumption of constant mass density.

Multilayer dielectric gratings (MLDGs) are crucial for pulse compression in picosecond–petawatt laser systems. Bulged nodular defects, embedded in coating stacks during multilayer deposition, influence the lithographic process and performance of the final MLDG products. In this study, the integration of nanosecond laser conditioning (NLC) into different manufacturing stages of MLDGs was proposed for the first time on multilayer dielectric films (MLDFs) and final grating products to improve laser-induced damage performance. The results suggest that the remaining nodular ejection pits introduced by the two protocols exhibit a high nanosecond laser damage resistance, which remains stable when the irradiated laser fluence is more than twice the nanosecond-laser-induced damage threshold (nanosecond-LIDT) of the unconditioned MLDGs. Furthermore, the picosecond-LIDT of the nodular ejection pit conditioned on the MLDFs was approximately 40% higher than that of the nodular defects, and the loss of the grating structure surrounding the nodular defects was avoided. Therefore, NLC is an effective strategy for improving the laser damage resistance of MLDGs.

Iodine is a vital trace element in the human body and is associated with several important coronary artery disease (CAD) risk factors. We aimed to explore the correlation between urinary iodine concentration (UIC) and CAD. Data from 15 793 US adults in the National Health and Nutrition Examination Survey (2003–2018) were analysed. We conducted multivariable logistic regression models and fitted smoothing curves to study the correlation between UIC and CAD. Furthermore, we performed subgroup analysis to investigate possible effect modifiers between them. We found a J-shaped association between UIC and CAD, with an inflection point at Lg UIC = 2·65 μg/l. This result indicated a neutral association (OR 0·89; 95 % CI 0·68, 1·16) between UIC and CAD as Lg UIC < 2·65 μg/l, but the per natural Lg [UIC] increment was OR 2·29; 95 % CI 1·53, 3·43 as Lg UIC ≥ 2·65 μg/l. An interaction between diabetes and UIC might exist. The increase in UIC results in an increase in CAD prevalence (OR 1·84, 95 % CI 1·32, 2·58) in diabetes but results in little to no difference in non-diabetes (OR 0·98, 95 % CI 0·77, 1·25). The J-shaped correlation between UIC and CAD and the interaction between diabetes and UIC should be confirmed in a prospective study with a series of UIC measurements. If excessive iodine precedes CAD, then this new finding could guide clinical practice and prevent iodine deficiency from being overcorrected.