ABSTRACT Often in approximate formulations for embedded foundations, the foundation-base is simulated using the expression of a rigid disk ‘on’ a half-space. However, a mechanistically more correct and rigorous treatment of the foundation-base would be to incorporate an expression of a rigid disk ‘in’ an open trench. In this paper, a formulation for the torsional dynamics of embedded foundation is shown in which the soil adjacent to the footing is modelled using the Vlasov-Leont′ev foundation model and the base-resistance is described through an expression of a rigid disk ‘in’ a half-space. From the comparative results, it is found, this formulation captures the foundation response at high values of pile-soil stiffness ratio, unlike, the expression of a rigid disk ‘on’ a half-space. Furthermore, from a parametric study, it is found, the pile-soil density ratio has a substantial effect on the foundation response. The extent of soil domain participating in the interaction process increases with the pile-soil stiffness ratio, and remains, more or less, unaltered/unaffected with increase in the dimensionless frequency and pile-soil density ratio.

Abstract High-purity fractionation of microparticles of different particle features is of great importance, especially in clinical diagnosis, recycling applications, and the food industry. We show that high-purity particle separation driven purely by hydrodynamic effects in a microchannel can be realized, achieving not only size, but also density and shape fractionation. For this, a microchannel with periodic contraction-expansion sections is used. A key feature of the method is that the Reynolds number at which a transition between particle equilibrium focusing regimes occurs decreases with increasing particle size, density, or aspect ratio. The evolution of inertial lift forces and centrifugal forces acting on individual particles is studied based on experimentally-determined, local features of the flow field, to gain a deeper insight into the particle migration dynamics. For this purpose, the General Defocusing Particle Tracking method is employed to reconstruct the three-dimensional positions of ellipsoidal and spherical particles. By enabling efficient, purely hydrodynamic separation of microparticles based on size, density, and shape, this approach opens new possibilities for passive separation in microfluidic applications.

The coastal communities of southern Kerala, though rich in cultural and ecological heritage, face mounting socio-economic challenges due to both natural and human-induced pressures. This study offers a comprehensive assessment of the socio-economic vulnerability of 253 villages spread across the coastal plains from Ernakulam to Thiruvananthapuram. Using data from the 2011 Census and household records, the research analyzes key indicators such as population and household density, child and female population ratios, literacy rates, primary workers, and socially weaker groups to evaluate levels of vulnerability. These indicators were spatially mapped and ranked to create a composite vulnerability index, providing a clear picture of where and why vulnerability is most pronounced. Geographic Information System (GIS) tools played a central role in visualizing and interpreting these spatial patterns. To deepen the analysis, hotspot mapping was carried out using the Getis-Ord Gi* statistic in ArcGIS, identifying statistically significant clusters of high vulnerability, particularly in villages located in Thiruvananthapuram, Kollam, and Alappuzha. Villages like Ochira, Arattupuzha, Attingal, and Vakkam emerged as major hotspots requiring immediate attention. The findings highlight the spatial disparities in vulnerability across districts and underscore the importance of localized, data-driven strategies for disaster risk reduction and sustainable planning. This study emphasizes the value of integrating socio-economic data with spatial analysis to better target interventions and build resilience among Kerala’s most at-risk coastal populations. Keywords: Disaster, Vulnerability, Kerala, GIS, Coastal plains

Abstract Gas turbine secondary air systems enable elevated turbine entry temperatures for increased cycle efficiency and work output. To prevent the ingress of hot mainstream gas into the turbine cavity, purge flow is supplied to the cavity from the upstream compressor. It subsequently exits the cavity through a rim seal into the mainstream gas-path (egress). The interaction between egress and the mainstream alters the endwall secondary flow structures that form within the rotor blade passage. Purge has a significantly lower temperature than the mainstream flow and so a non-unity purge-mainstream density ratio (DR) exists, with unknown implications on the endwall secondary flow. Phase-locked, ensemble-averaged Volumetric Velocimetry (VV) measurements of the flow field within the rotor blade passage were conducted using a 1-stage, optically accessible, rotating turbine test facility. The effect of DR was simulated by varying the concentration of purge CO2 to achieve three DR conditions: 1, 1.26 and 1.54. Pitch-wise and radial positions of the endwall secondary flow vortices were tracked using a non-local vortex detection method. A significant pitch-wise shift in the egress vortex occurred when the cavity sealing effectiveness was increased. An independent increase in either the non-dimensional sealing flow parameter (Φ0) or DR resulted in increased radial migration (h), annulus blockage ratio (ξ) and circulation (Γ) of the passage vortex. A new cavity-derived blowing ratio, Φe*, was developed.

ABSTRACT In the present investigation, the collisions of weakly nonlinear wave structures in an unmagnetized plasma comprising inertial ions, Vasyliunas–Cairns (VC) distributed electrons, and electron beams are analyzed based on experimental data. The study focuses on face‐to‐face collisions involving soliton–soliton, soliton–breather, and breather–breather interactions. To carry out this analysis, the extended Poincaré–Lighthill–Kuo (PLK) reductive perturbation method is employed, leading to the derivation of two coupled Korteweg–de Vries (KdV) equations. At a critical value of the number density ratio, two coupled modified Korteweg–de Vries (mKdV) equations are used to study soliton–soliton, soliton–breather, and breather–breather interactions of the ion‐acoustic wave. The effects of various plasma parameters—namely, the superthermality of electrons (), the nonthermality of electrons (), and the electron beam‐to‐ion density ratio () at equilibrium—on the colliding soliton profiles are examined. The plasma parameter values used in the analysis are taken from the interplanetary space environment.

Introduction Alteplase is known to increase the risk of blood-brain barrier integrity disruption, potentiating hemorrhage and edema. Evolving edema reduces chances of good functional outcomes. There is a paucity of studies that investigate the role of alteplase administration in subacute edema progression. Here we aim to associate alteplase administration in combination with the degree of reperfusion on edema, measured by net water uptake. Methods We included 115 patients from the MRCLEAN NO-IV trial with baseline, 24-h and 1-week follow-up non-contrast CT scans. The cohort consisted of patients who received intravenous thrombolysis (IVT)+ endovascular treatment (EVT) vs. EVT alone. Net water uptake (NWU) was calculated as a ratio of mean lesion density compared to its homologous, contralateral region-of-interest. Unadjusted linear regression analysis was performed to assess the association between NWU progression and alteplase administration, successful reperfusion [expanded Thrombolysis in Cerebral Infarction (eTICI)2B/3], and excellent reperfusion (eTICI2C/3). Adjusted regression analysis was performed to correct for potential confounders. Results IVT administration was not statistically significantly associated with NWU progression. Regardless of treatment arm, there was substantial increase in NWU during the first 24 h and 1 week post-stroke. In adjusted analysis, successful reperfusion was significantly associated with reduced NWU progression at 24 h (β = −4.6; 95% CI: −8.4, −0.80) and 1 week (β = −6.5; 95% CI: −11, −2.3). Conclusion Alteplase administration prior to EVT did not impact the subacute edema progression in our cohort, whereas successful reperfusion was strongly associated with reduced edema progression, particularly at later timepoints. These results suggest that alteplase administration according to current guidelines is unlikely to contribute to accelerated edema progression and emphasize that achieving high-grade reperfusion is crucial for reducing secondary injury.

Plating is widely used as a method to add the function of the plated metal only to the surface without changing the strength and other properties of the substrate.As a material for corrosion protection of steel, Al is mainly plated by hot dip plating method. If the substrate is a material that can resist high temperatures, such as steel, hot-dip plating is an appropriate method, but it is not applicable to materials such as plastics. Electroplating using ionic liquids is a candidate for plating on plastic materials because plating at temperatures below 100°C is required. In this study, Al electroplating on ABS resin and its color anodizing and Al electroplating on CFRP and its surface modification by anodizing are introduced.The electrolyte was 1-ethyl-3-methylimidazolium chloride (EmImCl)-AlCl3 ionic liquid mixed at a molar ratio of 1 : 2. As a leveling agent, 1,10-Phenanthroline was added to the ionic liquid. Copper electroless plated ABS resin and copper plates were used for the test and support electrodes, and Al mesh for the counter electrode. Electroplating was performed at a temperature of 60 oC and a pulse current density of 20 mA cm-2 (ton = 1 s, toff = 0.2 s) with an electric charge of 57.9 C cm-2. The Al plating was anodized in sulfuric acid and then colored with dye.In the Al electroplating on CFRP, the resin part of the CFRP surface was etched with sulfuric acid to prepare a surface occupied mostly by carbon fiber parts. Al mesh was used as the counter electrode and Al wire as the reference electrode. The current density and duty ratio of the pulsed electrolysis were the same as described above, and an electric charge of 115.8 C cm-2 was applied. The samples were then anodized in sulfuric acid, and the surface hardness after anodic oxidation was measured with a micro-Vickers hardness meter.In the Al plating on ABS resin electroless plated with Cu, about 20 µm of plating film was formed almost uniformly at the center and the edge of the substrate. The adhesion strength of the Al plated film on the resin substrate was 2.8 MPa. In the sample where color anodizing was performed on the Al plated film. It was confirmed that the Al plating film was colored with the dyes respectively and was at the same level as the anodized aluminum film on the bulk Al plate. In the case of Al plating on CFRP and its anodization, about 40 µm of Al plating was anodically oxidized to an oxide film of about 10 µm. The hardness of this film was 318 Hv, which is about 7 times harder than the 44 Hv of CFRP (PEEK resin part).

The morphology and types of inclusion, as well as the microstructure, fundamentally affect the properties of high-strength peritectic steel. Rare earth elements not only modify inclusions but also act on the transformation of the microstructure. In this paper, the evolution mechanism of yttrium for the inclusions and microstructure in high-strength peritectic steel was investigated through experimental testing and thermodynamic analysis. The results show that yttrium treatment can modify the main large-sized irregular inclusions into spherical or near-spherical rare earth inclusions, accompanied by a reduction in the number density, area fraction, average diameter, and aspect ratio of inclusions. The evolution route for the inclusions follows Al2O3 + MnS + Al2O3-MnS→Y2O3 + Y-O-S + Y-S + Y-O-S-MnS with yttrium addition. The microstructural characteristics of yttrium-free steel show significant differences from those of yttrium-containing steel. Compared to yttrium-free steel, the yttrium-0.015 wt.% steel shows a refined austenite structure with more uniform size distribution and the absence of grain boundary ferrite films. The Y2O3 and Y2O2S inclusions mainly formed in liquid steel were found along the austenite grain boundary to prevent the grain growth and the formation of ferrite films. Additionally, after adding rare earth yttrium, the fraction of high-angle grain boundaries (HAGBs) increases, together with a decrease in the fraction of low-angle grain boundaries (LAGBs) in steel. The research results can provide a theoretical basis for the application of adding rare earth yttrium to high-strength peritectic steel.

Abstract Soil microbial biomass (SMB) and stoichiometric ratios of carbon and nutrients in microorganisms are crucial to predict biogeochemical and nutrient cycling in terrestrial ecosystems, particularly under global change. Using SMB data from 1,288 studies in China, we mapped the distribution of microbial biomass carbon (MBC), nitrogen (MBN), and phosphorus (MBP) and their stoichiometric ratios using the random forest model. The stocks of MBC, MBN, and MBP in the topsoil (0–30 cm) were (mean with 25% and 75% quantiles), , and Tg, respectively; the corresponding stocks in the subsoil (30–100 cm) were Tg C, Tg N, and Tg P, respectively. The mean MBC/MBN, MBC/MBP, and MBN/MBP ratios in the topsoil were estimated to be 10, 29, and 3.9, respectively, and the corresponding ratios in the subsoil were 8.6, 19, and 2.5, respectively. Soil physico‐chemical properties (pH and moisture) are the main direct drivers of SMB and their stoichiometric ratios, while climate (temperature) indirectly affects SMB. Climate indirectly affects SMB by altering soil moisture and substrate availability, the physico‐chemical properties directly shape SMB content through habitat and resource constraints. The Coupled Model Intercomparison Project Phase 6 demonstrated that SMB stocks will increase until 2,100. Under the Shared Socioeconomic Pathway 5–8.5, SMB stocks increased, especially in the topsoil. Our study clarified SMB stocks and microbial stoichiometric ratios for soils up to 1.0 m depth and revealed the main drivers. We assessed SMB density and microbial stoichiometric ratios, compiled databases across climatic regions, and provided recommendations for regional C, N, and P management.

ABSTRACT Numerous spacecraft observations have revealed that particle velocity distributions in space plasmas often exhibit high‐energy tails, which can be effectively represented by non‐thermal models. In this study, the dispersion and damping characteristics of the bump‐on‐tail (BOT) instability are revisited using the Vlasov‐Poisson formalism of plasma kinetic theory for an isotropic, unmagnetized, and collisionless plasma. The core population is modeled by a Maxwellian distribution, while the high‐energy tails are described using one‐dimensional reduced Cairns and hybrid Vasyliunas‐Cairns (VC) distributions. The corresponding longitudinal dielectric response function is derived analytically and evaluated numerically using solar wind data. The effects of key physical parameters—such as temperature ratio, number density ratio, and the non‐thermality indices and —are systematically examined to assess their influence on the growth and damping rates of the BOT instability. The results demonstrate that the simultaneous presence of the two non‐thermality parameters ( and ) significantly alters the instability behavior. Moreover, temperature and density ratios are found to play a crucial role in modulating the instability characteristics. Overall, this investigation provides a comprehensive framework for understanding wave–particle interactions and energy transfer processes in non‐thermal space plasma environments such as the solar wind and magnetosphere.

Early deep brain stimulation attenuates parkinsonism progression in a neurotoxin-induced Parkinson's disease mouse model.

Abstract Understanding the reproductive behaviour of invasive species is crucial for developing control techniques. This study investigated the mating behaviour and reproduction of Philornis downsi , an invasive parasitic fly that is threatening the survival of endemic birds in the Galapagos Islands. An observational study describing the mating behaviour of P. downsi was combined with experimental studies examining factors (feeding on a hormone analogue that influences sexual maturity, density and sex ratio, and body size) that could increase the low reproductive success in the laboratory. Males actively pursue females in flight, mount them, land, and copulation occurs when the male inserts the aedeagus and the female extends her ovipositor toward the male. Copulation duration ranged from 2 to 13 min. Male–male interactions were observed and point to a behaviour that defends access to females. The addition of methoprene to the diet did not increase copulation frequency or mating success (sperm stored) and reduced female fecundity and survival. No effect of density or sex ratio was found in copulation frequency or mating success; however, females laid more eggs at higher densities with a male biased sex ratio, and more fertile eggs were found at high densities regardless of sex ratio. Additionally, we found no influence of body size of wild or laboratory-reared male or females on mating success in the laboratory. These results bring us closer to understanding the mating behaviour of P. downsi .

Recent studies on the planet-dominated regime of type II migration have demonstrated the presence of a correlation between the direction of massive planet migration and the parameter K that describes the depth of the gap opened by the planet. Indeed, it has been reported that high (low) values for the K parameter correspond to an outward (inward) migration. In this paper, we aim to understand the mechanism driving inward and outward migration and why these mechanisms are correlated with the gap depth. We performed a suite of 2D, live-planet, long-term simulations of massive planets migrating in disks with the hydro-code Fargo3D . We focused on a range of planet masses (1–13 m_ J) and disk aspect ratios (from 0.03 to 0.1). We analyzed the evolution of orbital elements and gap structure. We also studied the torque contributions from outer Lindblad resonances to investigate their role in the migration outcome. We find that while all planets initially migrate inward, those with high enough K values eventually enter a phase in which the torque reverses sign and migration turns outward, until the point where it stalls. This behavior is associated with eccentricity growth in the outer disk and changes in the gap structure. We identified the surface density ratio at the 1:2 and 1:3 outer Lindblad resonances as a key output diagnostic that are correlated with the migration direction. In general, this ratio regulates the migration for all the cases where the massive planet remains in an almost circular orbit and the outer gap region exhibits moderate eccentricity. This characteristic sequence of inward-reversal-outward-stalling can occur for a variety of K values. Thus, further work is required to identify the simulation input parameters that determine the onset of this sequence. Our results suggest that outward migration in the planet-dominated regime is primarily governed by the relative importance of the 1:2 and 1:3 resonances. Therefore, the gap profiles play a crucial role in determining the direction of migration.

Abstract In soil mechanics and geotechnical engineering, the influence of soil fabric on mechanical properties is a topic of fundamental importance, albeit one that is inherently complicated. This paper examines the evolution of small-strain shear modulus G 0 in saturated sands subjected to a sequence of long-term drained cyclic loadings, considering various initial soil fabrics induced by sample preparations methods, including moist tamping, dry tamping, dry deposition, and water sedimentation. The evolution trend of G 0 with loading cycles is intricately influenced by a combination of factors, including the initial soil fabric, specimen density, and cyclic stress amplitude ratio. Microscale pore size distribution of sand specimens, prepared using various methods and at different densities, was also quantified through X-ray technology to enhance the analysis and interpretation of the experimental findings (127 words).

Abstract. Metal layer forms as a result of meteoric ablation and exist as a layer of metal elements between approximately 80 and 105 km altitude, and it provides information about the physics and chemistry of the boundary between the atmosphere and space. There are some studies about the wind field disturbances in Mesosphere and Low Thermosphere (MLT) region and the plasma variations in ionospheric E-region during magnetic storms, but no study on the impact of storms on the metal atom layers in mesosphere. During the super substorm on 4 November 2021, the atmospheric metal layers were observed to decrease by observations from three lidars at the mid-latitudes of China. The Na, Ca and Ni densities on the storm day were significantly lower than in other days in October and November. The O/N2 column density ratio observed by the Global Ultraviolet Imager (GUVI) on the storm day was much higher than on quiet days, and the numerical simulation results demonstrate a substantial increase in atomic oxygen density at the heights of the metal layer. The increase in oxygen density may lead to the formation of more metal compounds, thus more metal atoms are consumed. This is an interesting phenomenon that magnetic storm can perturb the atmospheric metal layer through chemical reactions.

ABSTRACT We study the integer autoregressive model of order one with Poisson innovations. Focusing on the autoregressive parameter, we derive the large sample confidence distribution function and the confidence density. We then study the implied prior (the ratio of the confidence density to the likelihood), for which we obtain some approximate results valid near the endpoints of the unit interval. These results, as well as simulation studies, illustrate that the implied prior is not flat. However, we find by simulations and two empirical examples that for moderately large sample sizes, Bayesian credibility regions assuming a flat prior are very close to corresponding frequentist confidence regions.

The trend towards higher bypass ratios and downsized cores in modern compressors leads to locally reduced Reynolds numbers, intensifying flow separation and unsteadiness, which limits the reliability of RANS models and motivates the use of LES as a feasible and attractive high-fidelity approach for these conditions. In this paper, we assess the capabilities of low- and high-fidelity numerical tools for predicting the effects of varying incidence angles for a linear compressor cascade at a Reynolds number of 150,000 and a Mach number of 0.6 based on the inflow conditions. The comparison is supported by experiments carried out at the Transonic Cascade Wind Tunnel at the DLR in Cologne, which feature an incidence angle variation of plus/minus 5 degrees. Particular emphasis is put on the numerical setup to reproduce the cascade experiment, discussing the effects of spanwise domain size, axial-velocity density ratio and inflow turbulence. The effects of the incidence angle variation are studied on the basis of instantaneous and mean flow quantities with a focus on separation, transition and loss mechanisms.

Effect of density ratio on the stability of a Couette flow past viscoelastic compliant solid

The Richtmyer–Meshkov instability (RMI) develops when a planar shock front hits a rippled contact surface separating two different fluids. After the incident shock refraction, a transmitted shock is always formed and another shock or a rarefaction is reflected back. The pressure/entropy/vorticity fields generated by the rippled wavefronts are responsible of the generation of hydrodynamic perturbations in both fluids. In linear theory, the contact surface ripple reaches an asymptotic normal velocity which is dependent on the incident shock Mach number, fluid density ratio and compressibilities. In this work we only deal with the situations in which a shock is reflected. Our main goal is to show an explicit, closed form expression of the asymptotic linear velocity of the corrugation at the contact surface, valid for arbitrary Mach number, fluid compressibilities and pre-shock density ratio. An explicit analytical formula (closed form expression) is presented that works quite well in both limits: weak and strong incident shocks. The new formula is obtained by approximating the contact surface by a rigid piston. This work is a natural continuation of J. G. Wouchuk (2001 Phys. Rev. E vol. 63, p. 056303) and J. G. Wouchuk (2025 Phys. Rev. E vol. 111, p. 035102). It is shown here that a rigid piston approximation (RPA) works quite well in the general case, giving reasonable agreement with existing simulations, previous analytical models and experiments. An estimate of the relative error incurred because of the RPA is shown as a function of the incident shock Mach number $M_i$ and ratio of $\gamma $ values at the contact surface. The limits of validity of this approximation are also discussed. The calculations shown here have been done with the scientific software Mathematica. The files used to do these calculations can be retrieved as Supplemental Files to this article.

The identification of anomalous data objects within massive datasets is a critical technique in financial auditing. Most existing methods, however, focus on global outlier anomalies detection with less effective in contexts such as Chinese financial budget auditing, where local outliers are often more prevalent and meaningful. To overcome this limitation, a unified outlier detection framework is proposed that integrates both global and local detection mechanisms using k-nearest neighbors (KNN) and kernel density estimation (KDE) methodologies. The global outlier score is redefined as the sum of the distances to the k-nearest neighbors, while the local outlier score is computed as the ratio of the average cluster density to the kernel density—replacing the cutoff distance employed in Density Peak Clustering (DPC). Furthermore, an adaptive adjustment coefficient is further incorporated to balance the contributions of global and local scores, and outliers are identified as the top-ranked objects based on the combined outlier scores. Extensive experiments on synthetic datasets and benchmarks from Python Outlier Detection (PyOD) demonstrate that the proposed method achieves superior detection accuracy for both global and local outliers compared to existing techniques. When applied to real-world Chinese financial budget data, the approach yields a substantial improvement in detection precision-with 38.6% enhancement over conventional methods in practical auditing scenarios.