Alkaline hydrolysis coupled with array gas membrane separation device and HPLC-FL for the determination of metformin in complex samples.

ABSTRACT The novelty of this letter lies in preliminarily analysis of the wave mapping mechanism using Gaofen-3 (GF-3) acquired in extended wide (EW) mode at low incidence angle of 10–20°. In total, 35 Chinese GF-3 images in vertical-vertical (VV) were collocated with hindcasted wave spectra from the numeric model WAVEWATCH-III (WW3). Validation of WW3-simulated significant wave heights (SWHs) against the Haiyang-2 (HY-2) altimeter wave products yields a root mean squared error (RMSE) of 0.44 m with a correlation coefficient (r) of 0.94 and a scatter index (SI) of 0.19, confirming the reliability of the WW3 simulations for this study. Subsequently, the synthetic aperture radar (SAR) intensity spectrum is simulated by multiplying the hindcasted wave spectrum by three modulation transfer functions (MTFs), i.e. tilt, hydrodynamic modulation, and velocity bunching. Based on experimental results, the spectrum correlation coefficient (Cor) and the spectrum squared error (E) of total energy between SAR intensity spectra and simulations using three MTFs are 0.94 and 7.79, respectively. These values represent significant large compared to other MTF combinations, which yield higher errors (approximately 6 E) and lower correlations (around 0.91 Cor). Therefore, it is concluded that velocity bunching has less influence on SAR mapping mechanism at low incidence angle, which is further supported by the Shapley Additive exPlanations (SHAP) analysis performed using eXtreme Gradient Boosting (XGBoost). This study establishes the foundation of wave retrieval from SAR image at low incidence angle.

• The analytical model for the interpretation of a Harmonic Pulse Test (HPT) in naturally fractured geothermal reservoirs is derived. • The radial composite effect due to the thermal front is also considered. • Differently from Pressure Transient Analysis, neither a preliminary well closure nor the closure of neighbor wells is required. • Synthetic validation is provided against established analytical and numerical models. • The HPT is suitable for thermal front monitoring during ongoing operations in naturally fractured geothermal reservoirs. Well testing and conventional Pressure Transient Analysis (PTA) are fundamental and well-established methodologies for characterizing well and reservoir parameters. However, the applicability of PTA is limited during production or injection operations, since it requires a shut-in of the tested well, and it is significantly affected by interferences from neighboring wells. In previous works, we proposed, implemented, and validated against real data a methodology called Harmonic Pulse Testing (HPT). HPT is complementary to PTA. By specifically deploying the periodicity of rate and pressure signals, it has been designed to be applied during ongoing field operations. In this work, we present a new analytical solution for HPT in naturally fractured reservoirs. The proposed solution is also applied to geothermal systems, as it is coupled with a radial composite model capable of approximating the thermal front. The model has been validated against well-established analytical and numerical models under different scenarios. The calculation steps for converting the numerical dual-porosity model into storativity ratio and inter-porosity flow coefficient are also provided. The results of a validation exercise demonstrate that our model is robust against potential interference from other wells and allows the detection of the thermal front. The methodology can therefore be successfully applied during ongoing operations in naturally fractured geothermal reservoirs.

With the rapid growth of the electric vehicles with drive systems with higher voltages, power outputs, frequencies, and speeds, mitigating electrically induced bearing damage (EIBD) in electric motors has become critical. In this study, a novel numerical model characterizing discharge-induced current density and voltage drop at the elastohydrodynamic lubrication line contact interface is presented. The current density and voltage drop constitute a linear complimentarily problem, which is efficiently solved using the conjugate gradient method. This paper sheds light on electrical characteristics at the inaccessible lubrication interface during discharge, highlighting the significance of roughness radius of curvature on current density. This numerical model lays the groundwork for future research on mitigating or even permanently solving EIBD problems in electric motor bearings. • An electrified EHL line contact with discharge is modeled numerically. • Interfacial current density and voltage drop constitute a linear complimentarily problem. • EHL contact transits from capacitive to resistive type as the electrical load increases. • Higher frequency components of the rough surface increase the local current density.

Numerical modelling of wave-current-seabed-pipeline system: pore pressure dynamics and pipeline stability in liquefiable seabed

Experimental and numerical investigation of transient responses and mooring tensions of SFT induced by sudden mooring failure

In our previous work, microwave regeneration of 30 wt% ethanolamine solvents in a hollow fiber gas-liquid contactor was studied. In this system, the solvent was heated by microwaves as it traversed a microwave applicator while passing through the lumen of the hollow fiber. Experimental results do not provide insight into the operation of microwave regeneration. The aim of this study is therefore to develop a model to simulate the microwave solvent regeneration in the single fiber system. The numerical approach is based on coupling 3D microwave heating of solvent flow, and 1D chemical desorption of CO 2 applicable to non-isothermal conditions along the fiber. The model was successful in reproducing with reasonable accuracy the global desorption data from the regeneration experiments, assuming a low wetting fraction of the membrane. The effects of operating conditions were explored: results show that increasing the solvent flow rates induces higher temperature gradients at the boundary of the fiber lumen thus increasing desorption rates. It has been found that increased fiber radius leads to better desorption rates at the expense of lowering the interfacial surface density. On another note, numerical results show that isothermal regeneration performs better than microwave mode although the latter is able to outperform where hotspots persist along the fiber. With regards to flow configurations during microwave regeneration, counter-current mode performed better than co-current one: the sweeping gas in the former mode passes from the hot solvent side to the cold solvent side which encourages reabsorption of the desorbed CO 2 .

Antibacterial mechanism of octyl gallate against methicillin-resistant staphylococcus aureus and its application in pork preservation: insights from multi-omics and computational simulation.

Subaortic stenosis, a heart disease characterised by a narrowing of the left ventricular outflow tract, is frequently caused by the presence of a subaortic membrane (SAM) located at the aortic valve inlet. This anatomical obstruction leads to significant haemodynamic alterations and leaflets fluttering, whose mechanisms are not yet fully understood. This research investigates, through computer simulations, the SAM's haemodynamic impact and the mechanism behind leaflets fluttering. A mono-physics fluid-structure interaction approach, based on the meshless smoothed particle hydrodynamics method, was employed. This approach represents both blood and structures with particles without defining interfaces, efficiently capturing large deformations and dynamic phenomena. Two common types of SAMs were investigated - a discrete thin SAM layer (flexible) and a thick fibromuscular ridge SAM (stiff) - and compared with a healthy aortic valve. Projected dynamic valve area (PDVA) was used as a reference parameter to quantify leaflet oscillation. While the PDVA in the healthy aortic valve stabilised at 283mm2 without oscillation, both pathological cases exhibited self-sustained periodic fluctuations. In the presence of discrete thin SAM layer, the mean PDVA decreased by 3% compared to the healthy control. This reduction was more pronounced for thick fibromuscular ridge configurations, where the mean PDVA was 9% lower than the healthy case. Notably, stiffer SAM configurations more than doubled the oscillation amplitude (from 3.12mm2 to 6.77mm2) and increased the oscillation frequency by 8% relative to flexible membranes. Vortices dynamics was analysed, determining the phases of their formation, growth and migration. Through the analysis of velocity, vorticity, and shear stress maps, this study provides critical insights into the origin of fluttering and its influence over these key haemodynamic parameters. Findings demonstrate that the oscillatory leaflet motion is the result of vortices formation and shedding. The stiffness of the SAM significantly modulates the fluttering behaviour. While structural damage and haematological complications were not directly simulated, the identified oscillations represent haemodynamic conditions associated in literature with such pathologies. The observed alterations in wall shear stress magnitude and direction provide a physical basis for the mechanical environment that could contribute to endothelial cell dysfunction in the presence of SAM.

Identifying myocardial regions perfused by coronary arteries through detailed human microvasculature data.

Liquiritigenin targets transferrin receptor to potentiate ferroptosis sensitivity in colorectal cancer cells.

Environmental and technical assessment through computer simulation and design of a solar hybrid power plant with MSF/TVC-MED/TVC desalination

Uranium is the main raw material for nuclear energy, which is an alternative to renewable energy sources. In nature, hexavalent uranium (U(VI)) is the most stable and highly soluble form. U(VI) present in deep repositories created for the disposal of radioactive waste or nuclear reprocessing can leach into water systems, posing environmental and human health risks. Therefore, uranium species must be removed from the environment. Adsorption is considered an efficient technique for removing uranium from water resources based on the ease of adsorption on bioadsorbents such as cellulose, hemicellulose, and lignin compounds. Therefore, this study evaluated the adsorption mechanisms of uranyl ions ( UO 2 2 + ) from an aqueous medium onto cellulose (CE), hemicellulose with arabinose groups (Hm1) and without arabinose groups (Hm2), and lignin with coniferyl and sinapyl groups (GS) matrices via computer simulations. The adsorbate-adsorbent systems were optimized, and it was observed that among the matrices, UO 2 2 + exhibited the highest interaction energy with CE owing to its abundant hydroxyl groups, followed other matrices with increasingly weaker interactions. All evaluated interactions were exothermic (Δ r H < 0) and almost all were spontaneous (Δ r G < 0), except for Hm1– UO 2 2 + 1 and GS– UO 2 2 + 1 . The topological parameters obtained by the quantum theory of atoms in molecules showed that all types of interactions are non-covalent, in which the interactions between uranium atoms and the oxygen atoms in the matrices are partially covalent, and those between the oxygen atoms of UO 2 2 + and the hydrogen atoms of the matrices are electrostatic. These trends were confirmed by the isosurface graphs obtained from non-covalent interaction analyses, which identified strong adsorbent U O interactions and weak Van Der Waals O adsorbate –H adsorbent interactions. Thus, it was concluded that unmodified cellulose, hemicellulose and lignin are good adsorbent matrices for removing UO 2 2 + from water resources. The theoretical studies on the adsorption mechanisms of cellulose, lignin, and hemicellulose matrices shown in this work can provide insights into the interaction mechanisms and enhance our understanding of UO 2 2 + ∙∙∙biopolymer interactions during environmental remediation processes. • DFT study of uranyl ion UO₂ 2+ adsorption on cellulose, hemicellulose, and lignin. • Identification of the most stable adsorption sites and coordination modes for U(VI). • Lignocellulosic biopolymers are proven effective eco-friendly adsorbents for uranium recovery. • Calculated Gibbs free energies ($\Delta G < 0$) confirm the spontaneity of the uranium removal process in aqueous media.

While the heterogeneity and co-occurrence of heritable neurodevelopmental conditions such as autism, attention deficit hyperactivity disorder (ADHD), and dyslexia remain issues of debate, these conditions are nevertheless all characterised by uneven cognitive profiles exhibiting strengths and weaknesses. There have been advances in understanding neural markers and genetic predictors of these conditions, but little insight into how DNA variation can influence functional brain development in such a way as to produce uneven cognitive profiles as developmental outcomes. Uneven cognitive profiles (e.g., across verbal and non-verbal intelligence) also characterise individual differences, and similarly, their genetic basis is little understood. Two main sources of uneven profiles appear possible: that there are regional genetic effects on brain development that act on mechanisms which play an influential role in the development of a particular cognitive or socioemotional ability (domain-specificity); or that genetic effects on brain development have a more widespread influence on neurocomputational properties, but the development of particular abilities is differentially sensitive to variation in those properties (domain-relevance). In this article, we present computational simulations that combine genetic algorithms and artificial neural networks to explore the second of these possibilities, domain relevance. Selection is used to alter the population frequency of alleles that influence the neurocomputational properties of a common substrate, under a polygenic model. Different regions of the substrate become specialised for developing different functions, modelled by five tasks. Across 20 generations, we assess how selection for a given task, which serves to tune substrate-wide neurocomputational properties in favour of this task, serves to alter the development of the other four tasks, which must employ the same range of neurocomputational properties. We demonstrate that such selection can enhance or impair acquisition in non-selected domains, depending on the computational demands of each task domain. We also show that behavioural deficits associate with an increase in the heritability of individual differences. We discuss the results in the context of contemporary theories of the influence of genetic variation on functional and structural brain development, and assess the merits of the domain-specific and domain-relevant accounts of uneven cognitive profiles in neurodevelopmental conditions and individual differences. SUMMARY: Heritable neurodevelopmental conditions such as dyslexia, attention deficit hyperactivity disorder, autism, developmental language disorder, and developmental coordination disorder are characterised by uneven cognitive profiles. However, little is known about how genes produce such uneven cognitive profiles. It is a puzzle because genetic effects on brain development are typically more widespread than areas showing functional specialisation in adults. The work presents computational modelling to demonstrate how the relationship between cognitive domains and processing properties of a substrate constrains behavioural development. A common substrate for different domains (such as association cortex in a cortical lobe), where domains are specialised to different regions with shared properties, may exhibit uneven cognitive profiles if the processing properties of the substrate are better tuned to supporting some domains than others (so-called domain-relevance). Simulations then test the hypothesis that domain relevance is a plausible mechanism for explaining how common genetic variation might contribute to specific and uneven cognitive profiles seen in neurodevelopmental conditions. The computational simulations therefore give insight into how conditions such as dyslexia may emerge, why they would be heritable, and why the relationship between genotype and phenotype in common neurodevelopmental conditions is likely to be highly polygenic.

Innovative approaches for estimating the efficiency of a single-tilt solar still: a comprehensive theoretical and numerical analysis

• Local and local–flexural interactive buckling behaviour of ferritic built-up I-section columns was studied. • Tests were conducted on ten ferritic stainless steel built-up I-section column specimens. • FE models were validated against test results and then used for parametric studies. • Accuracy and reliability of the codified design rules were assessed based on test and FE data. Cold-formed steel built-up section members have attracted increasing interest due to their potential to provide higher load-carrying capacities than conventional single-section members. Ferritic stainless steels, characterised by their low nickel content, offer a cost-effective and sustainable alternative to austenitic grades, while maintaining adequate mechanical properties and corrosion resistance. This paper investigates the structural behaviour and capacity of ferritic stainless steel built-up I-section columns failing by local buckling and local–flexural interactive buckling. An experimental programme was first conducted, including tensile coupon tests, measurements of initial global and local geometric imperfections, and axial compression tests on ten built-up I-section column specimens. Each specimen comprised two identical press-braked ferritic stainless steel channel sections connected using self-drilling screws. Subsequently, finite element models were developed and validated against experimental results. Parametric studies were carried out to discuss the effects of key design parameters. The accuracy and reliability of the codified Effective Width Method and Direct Strength Method in predicting the capacities of ferritic stainless steel built-up I-section columns were evaluated, indicating that: (i) the Effective Width Method offers consistently conservative predictions, underestimating column failure loads by 10% on average; (ii) the Direct Strength method yields greater scatter but improved accuracy, underestimating load-carrying capacities by an average of 1%; (iii) the Effective Width Method provides accurate and consistent predictions for columns failing by local buckling, while its predictions for local–flexural interactive buckling are more scattered and conservative; (iv) both methods exhibit increasingly conservative and scattered predictions as the column slenderness increases. In summary, the existing codified design methods specified in AISI S100 can be extended to the design of ferritic stainless steel built-up I-section columns.

Deciphering solute transport in crack networks-clay matrix systems: Insights from experiments and numerical modeling

Point fixed glass façade systems (PFGFSs) are critical modern building envelopes that merge architectural appeal with structural and thermal performance, yet lack robust methodologies for dynamic simulation and risk assessment. This study bridges the gap by developing a highly accurate, computationally efficient numerical benchmark model for full-scale PFGFSs validated against in-plane cyclic loading tests. The model integrates component-level validation of laminated glass panels (including interlayer effects), stainless steel spider arms, and carbon steel substructure to ensure physical fidelity while employing a simplified yet high-fidelity finite element approach to minimise computational cost without sacrificing precision. System-level validation demonstrated excellent agreement with experimental results, capturing critical behaviours such as dominant principal tensile stresses, elevated inner-layer glass stresses, and frame lateral resistance—key insights for seismic design. The results demonstrated strong performance in two evaluation metrics, accuracy and computational efficiency. the benchmark model achieved an average difference of 4.75% in reaction forces, indicating high accuracy, and required only 5% of the computational time compared with existing numerical models of the same experimental test. These outcomes highlight the efficiency and reliability of the developed benchmark model. By balancing accuracy with computational simplicity, this benchmark model provides a reliable foundation for seismic risk assessments and performance-based design, offering researchers a practical tool to enhance the safety and efficiency of modern façades.

Understanding and modeling phase change inside a cryogenic hydrogen tank of a rocket upper stage or an envisioned fuel depot is essential to enable future exploration goals. Boiling under compensated gravity conditions is caused by local hot spots and influences the thermodynamic state of the fluid, the position of the liquid, and can cause a rise in system pressure. Modeling the boiling process which ranges from the micrometer scale of the cavity at the tank wall to the millimeter scale of the vapor bubbles is important in order to predict the full fluid behavior in the tank. Empirical data for individual hydrogen vapor bubbles under compensated gravity does not exist in literature and is a valuable baseline for analytical and numerical models. The lack of buoyancy increases the observation time and leads to larger bubbles which are better suited for evaluation. In the presented work, the growth of singular hydrogen vapor bubbles for a time of 3.6 s under isobaric conditions has been caused and observed. The growth was initiated at an artificial nucleation site with a diameter of 92.4 µm and a depth of 310 µm by dissipating a known heat flow. The bubble growth data is unique because the defined system conditions allow for a precise correlation of the applied stimuli to the growth behavior. • Isobaric boiling of individual bubbles in a cryogenic hydrogen system. • Cryogenic experiments under microgravity conditions. • Bubbles stays at nucleation site due to absence of buoyancy. • Artificial cavity was manufactured for cryogenic hydrogen fluid system. • Experimental data for liquid hydrogen is relevant for depots and upper stages.

A new rock cutting and splitting method for hard-rock excavation: methodology, scaled model test and numerical modelling, and field validation