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In this paper, the energy absorption performance of braided composite tubes under combined shear-compression loading is investigated. ABAQUS/Explicit is employed to analyze the energy absorption of braided composite tubes, and quasi-static compression tests are carried out. Braided composite materials absorb energy through the damage accumulation in laminate. Thus, to maximize energy absorption performance, a progressive crushing mode should be induced. While extensive research has been conducted on cases of axial loading, understanding of the energy absorption performance of braided composite tubes under combined shear-compression loading remains limited. Experimental results reveal that under both axial and combined shear-compression loading at 30 degrees, the braided composite tube exhibits a progressive crushing mode. The test results are utilized to validate the finite element model. Through finite element analysis, it is confirmed that the damage accumulation in laminate is maximized due to the induction of a progressive crushing mode. It means that the energy absorption principles of braided composites apply similarly to combined shear-compression loading, allowing for the maintenance of superior energy absorption performance of braided composites under various load angles. [ABSTRACT FROM AUTHOR]

Abstract3D additive manufacturing of metamaterials, especially honeycomb structures, has gained prominence in industrial manufacturing for their exceptional mechanical properties and energy absorption (EA) capabilities. This study introduces a novel circular tubular honeycomb structure to enhance EA characteristics. Through quasi-static compression experiments and finite element simulations, specific energy absorption (SEA) of various circular structures is analyzed. Results show that the circular tubular honeycomb structure excels in SEA performance, lightweight construction, and reduced Poisson’s ratio. An equation for structural neutral layer offset is derived and validated, showcasing potential in thin-walled pipe-in-pipe (PIP) interlayers. [ABSTRACT FROM AUTHOR]

Yamanashi et al., conducted a study on the absorption of cholesterol and β-sitosterol, as well as the inhibitory effect of ezetimibe (EZE). They used CaCo-2 cells to simulate the intestines and investigated how different mixed micelles, acting as carriers, were absorbed into these cells through the Niemann-Pick C1-like 1 (NPC1L1) protein. The study focused on the impact of micelle shape, size, and zeta potential on absorption and the inhibitory effect of EZE. I utilized small-angle X-ray scattering and a zeta potential measuring device to measure these characteristics. The findings revealed a two-step mechanism: NPC1L1 selectively bound micelles based on their shape and size, and once bound, the absorption was regulated by the molecular structure of the micelle components. EZE's inhibitory effect changed with micelle composition, influencing micelle size and shape. EZE initially acted on the micelle's shape and size, and then NPC1L1 selectively bound micelles based on their shape and size, allowing EZE to directly inhibit absorption by interacting with NPC1L1. This groundbreaking discovery challenges existing concepts and holds significant implications for researchers in drug development, as well as physicians and pharmacists. [ABSTRACT FROM AUTHOR]

Microplastics have become a ubiquitous contaminant, but their fate in food animals is largely unknown. In this study, [14C]-polystyrene microplastic (PS-MP) particles were orally dosed to lactating sheep to evaluate their absorption and disposition. Elimination of the [14C]-PS-MP was predominately through faeces with faecal radioactivity peaking at 24 h post-dosing but continuing to be present throughout the entire 72 h study period. Only a small fraction (≤ 1%) of the dosed [14C]-PS-MP was present in blood, milk, and urine. Pharmacokinetic analysis of blood plasma radioactivity, using non-compartment modeling, indicated rapid absorption (T1/2 0.4 to 3 h) with slow elimination (T1/2 37 to 48 h). Radioactivity in milk and urine had similar elimination patterns with radiocarbon activities peaking 24 h post-dosing with detectable elimination throughout the 72 h study period. No radioactivity was quantifiable in tissues at the 72 h withdrawal period. [ABSTRACT FROM AUTHOR]

The modern additive manufacturing process enables the fabrication of innovative structural designs of lattice structures with enhanced mechanical properties. Characterizing the designability of lattice geometries and the corresponding mechanical performance, particularly the compressive strength is vital to commercializing lattice structures for lightweight components. In this paper, a Novel hybrid type of lattice structure was developed inspired by the overlapping pattern of scales on dermal layers of the species like fish and circular patterns observed from the bamboo tree structure. This research designed the lattice cell with 20%,30%,40%, and 50% overlapping areas based on the proposed circular area. The unit cell wall thickness varies between 0.4 mm and 0.6 mm. The designed structures with a constant volume of 40x40x40 mm, varied circular diameters, overlapping areas, and unit wall thickness are modeled in Fusion 360 software. 3D-printed lattice structures were fabricated using the vat polymerization type three-dimensional printing machine using the principle of stereolithography (SLA) technique. Then, the 3D-printed specimens are tested for quasi-static compressive response in a universal testing machine (UTM) by following ASTM standards. The test results are evaluated and compared with the simulation results. Finally, the best lattice structure is selected for energy absorption application in the aerospace and defense sectors. [ABSTRACT FROM AUTHOR]

The combined effect of active shielding packaging and relative phase sweeping on heating performance in a dual-port solid-state microwave heating process was evaluated. Four types of heating strategies that combine two factors (passive and active packaging and fixed and sweeping relative phase) were used in heating a tray of 300 g gellan gel sample for 3 min. The temperature distributions at the top and middle layers of the heated samples were collected and analyzed for heating uniformity index (HUI) and power absorption efficiency (PAE). The results showed that both active shielding package and relative phase sweeping can individually improve the HUI while maintaining high PAE. The packaging factor and relative phase factor showed a significant interaction effect (p = 0.0021) in influencing HUI but not PAE, highlighting the necessity of considering both factors (packaging and relative phase) when optimizing the microwave heating uniformity. The combination of active packaging and sweeping relative phase is a robust heating strategy that delivers the best heating performance that is significantly better than or similar to other combinations of packaging and relative phase strategies. [ABSTRACT FROM AUTHOR]

Selecting the appropriate surfactant as a foaming agent is crucial in the production of foamed concrete. In this study, multiple technological approaches were employed for the investigation of the effect of three different types of surfactants as foaming agents; the approaches included surface tension measurement, zeta potential analysis, spectrophotometry, and nanoindentation. The results showed that the surface activity, solution viscosity, and environmental pH all influenced the generation and stability of foam in foaming agents. The adsorption process of surfactants onto cement particles was complex and could be effectively explained using the double-layer theory. The adsorption of anionic surfactant molecules on cement particles significantly altered the zeta potential, up to −17 mV, with an adsorption efficiency over 10 times greater than that of cationic surfactants and more than 5 times greater than that of nonionic surfactants. Furthermore, after cement hardening, the mechanical properties of the resulting pores were notably improved due to the presence of adsorbed anionic surfactants, and the maximum compressive strength could exceed 10 MPa. [ABSTRACT FROM AUTHOR]

AbstractUnder compressive loads, shear band formation in lattice structures can lead to stress fluctuations, resulting in a decrease in energy absorption capacity. To specifically suppress shear bands, it is necessary to expound the formation mechanisms. This study used theoretical analysis, experiments, and finite element (FE) simulations to elucidate the mechanism underlying shear band formation in strut-based lattice structures. It was determined that stress concentration at strut joints along the 45° diagonal plane induced shear deformation. Shear bands were most pronounced along the four body diagonals, and their existence diminished as the distance from the diagonal increased. Therefore, a design of oblique graded lattice structure (OGLS) was proposed, and quasi-static compression experiments were performed using FE method. The results showed that the main internal stress of OGLS is combined with the original 45° shear stress and the annular staggered stress produced by the oblique graded design, which constrains each other and avoids mutual dislocation deformation, thus realizing shear band suppression. However, an excessively large graded coefficient excessively weakens the 45° shear stress and results in the appearance of an annular compact band. By optimizing the graded coefficient based on the deformation consistency of the outer contour, the optimized OGLS exhibited significant improvements in yield strength, plateau stress, and energy absorption, which are increased by 36.06%, 39.29%, and 34.41%, respectively. This research offers novel perspectives on how lattice structures can attain stable compression deformation and a high energy absorption capacity. [ABSTRACT FROM AUTHOR]

AbstractThe design of heat exchangers plays an important role in the performance of solid-state hydrogen storage devices. In this study, three different designs of hydrogen storage devices were investigated, incorporating phase change material (PCM), specifically, RT25HC into their walls in various shapes. A mathematical model, validated using previous experimental data, was employed to calculate heat and mass transfer and determine the reaction time period. The calculations were conducted using ANSYS Fluent, with a constant hydrogen supply pressure of 10 bars and a temperature of 295 K. The absorption properties of the storage reactor were investigated through various parameters such as liquid fraction, hydrogen concentration, and natural convection heat transfer coefficients. Results showed that the geometric structure and PCM distribution significantly impacted the performance of the hydrogen storage devices. Design 1, with a centralized PCM distribution, demonstrated moderate heat transfer rates and a longer reaction time. Design 2, featuring a more distributed PCM layout, improved heat transfer rates and reduced hydrogen kinetics time by 40%. Design 3, which optimized the geometric structure with advanced PCM shapes, achieved the highest heat transfer rates and improved hydrogen kinetics time by 50%. This design also enabled the storage of thermal energy at a high density, ranging from 10.2 J/g to approximately 190.5 J/g. The study provides critical information on the design of efficient solid hydrogen storage processes. The findings suggest significant potential for improved performance in industrial applications such as electric vehicles and domestic energy supply. The high efficiency of the large-scale reactor is due to its well-designed system, which effectively converts chemical energy into thermal energy. Optimizing the reactor geometry and PCM distribution is crucial for achieving superior hydrogen storage and retrieval performance. [ABSTRACT FROM AUTHOR]

AbstractDrawing inspiration from hierarchical structures, axisymmetric design layouts were introduced, and hybrid hierarchical chiral structures (HHCS) based on four- and six-chiral structures were proposed. The performance of HHCSs under in-plane compression is investigated using finite element methods and experiments. The effect of different loading conditions on the behavior of HHCSs is discussed. Under low-speed impact, HHCSs exhibit a negative Poisson’s ratio (NPR) effect, which diminishes as the velocity increases and the inertial effects gradually become dominant. The parameter study shows that increasing the connectivity between subunits and the thickness can enhance the energy absorption capacity of the structure while maintaining a good NPR effect. The conventional inclined deformation mode of the chiral structure is improved by the axisymmetric layout, which effectively improves the energy absorption. [ABSTRACT FROM AUTHOR]

To enhance the out-of-plane mechanical performance, a novel honeycomb with arc-curved edge is proposed. The numerical model is built based on the elastoplastic failure criterion. The impact performance of proposed honeycomb is investigated and revealed. The influence of central angle and thickness on the crashworthiness is researched. The results show that the numerical result is in agreement with that of experimental test. The central angle has great influence on the deformation mode. The global buckling of edge tube is exhibited for the small central angle, and the consistent deformation mode is demonstrated for the central area. With the increasing of central angle, the energy absorption ability is enhanced for the plastic hinge could absorb more impact energy. The more stable deformation mode is exhibited for the larger central angle. The honeycomb with relatively large central angle has the best crashworthiness performance for the balance of energy absorption and structural mass. Compared with traditional honeycomb, the proposed honeycomb could improve the out-of-plane energy absorption characteristics. [ABSTRACT FROM AUTHOR]

AbstractSandwich structure is a lightweight structure with high specific strength and specific stiffness, as well as excellent energy absorption and load-carrying capacity. Sandwich structures are widely used in aerospace, high-speed rail and marine applications. Low-velocity impact of a sandwich beam with foam-filled sinusoidal corrugated core is investigated by means of theoretical derivations and numerical calculations. A yield criterion is used to obtain an analytical solution of the dynamic behavior of champed sandwich beams with foam-filled sinusoidal corrugated cores under low-velocity impact. Numerical calculations are performed. The analytical results are in excellent accordance with the finite element results. Influences of the amplitude, half-wavelength and thickness of the sinusoidal corrugated plate, foam strength, metal-sheet strength, and the impact location on the dynamic behavior of the sandwich beams with foam-filled sinusoidal corrugated cores under low-velocity impact are discussed. The present analytical model can predict reasonably well the dynamic behavior of foam-filled sinusoidal corrugated core sandwich beams under low-velocity impact. [ABSTRACT FROM AUTHOR]

A Lamb dip spectroscopic measurement of the Q(1) transition in the (2-0) overtone band of ortho- $ \hbox {H}_2 $ H 2 is performed with the ultra-sensitive NICE-OHMS intracavity absorption technique at $ 1238\,\hbox {nm} $ 1238 nm . For the first time individual hyperfine components of a vibrational transition in $ \hbox {H}_2 $ H 2 are resolved, displaying a pattern of 4 overlapping components with singly isolated components at the red and blue side. Weak components at a line strength of $ 4.4 \times 10^{-28} $ 4.4 × 10 − 28 cm/molecule could be observed as a Lamb dip. Analysis yields a hyperfineless purely rovibrational transition frequency for the Q(1) (2-0) line in $ \hbox {H}_2 $ H 2 at unprecedented accuracy for any rovibrational transition in a molecular hydrogen isotopologue. Its frequency is 242,091,630,140 $ \,(9)\,\hbox {kHz} $ (9) kHz under the assumption that only a blue recoil component is observed. A 1.7σ deviation from the most advanced quantum electrodynamics calculations is obtained, forming a challenge for theory. [ABSTRACT FROM AUTHOR]

AbstractSanguinarine (SAN) is an alkaloid with multiple biological activities, mainly extracted from Sanguinaria canadensis or Macleaya cordata. The low bioavailability of SAN limits its utilization. At present, the nature and mechanism of SAN intestinal absorption are still unclear. The pharmacokinetics, single-pass intestinal perfusion test (SPIP), and equilibrium solubility test of SAN in rats were studied. The absorption of SAN at 20, 40, and 80 mg/L in different intestinal segments was investigated, and verapamil hydrochloride (P-gp inhibitor), celecoxib (MPR2 inhibitor), and ko143 (BCRP inhibitor) were further used to determine the effect of efflux transporter proteins on SAN absorption. The equilibrium solubility of SAN in three buffer solutions (pH 1.2, 4.5 and 6.8) was investigated. The oral pharmacokinetic results in rats showed that SAN was rapidly absorbed (Tmax=0.5 h), widely distributed (Vz/F = 134 L/kg), rapidly metabolized (CL = 30 L/h/kg), and had bimodal phenomena. SPIP experiments showed that P-gp protein could significantly affect the effective permeability coefficient (Peff) and apparent absorption rate constant (Ka) of SAN. Equilibrium solubility test results show that SAN has the best solubility at pH 4.5. In conclusion, SAN is a substrate of P-gp, and its transport modes include efflux protein transport, passive transport and active transport. [ABSTRACT FROM AUTHOR]

In this paper, the technique of surface absorption of a uniform laser radiation is used to illuminate the upper surface of a thermoelastic layer whose properties are temperature-dependent utilizing the new modification of Green's and Lindsay's thermoelasticity theory. The upper surface of the layer is exposed to heat losses and the lower surface is considered insulated, while both are traction free. The general solution of the problem obtained by applying Laplace transform in which whose inverse obtained computationally. In addition to the usual temperature-dependent consideration, we also investigate the case of temperature-dependent absorption coefficient of the surface. [ABSTRACT FROM AUTHOR]

This paper presents a review of the literature, published in the last 5 years, reporting antimicrobial compounds and factors affecting the release, absorption, and concentration in food packaging. This overview shows that concentration of natural antimicrobials plays an important role in bacterial inhibition to prolong food shelf life in antimicrobial packaging. The extension of bacterial inhibition depends on antimicrobial stability inside the packaging system, where the antimicrobial concentration should be maintained above the minimum inhibitory concentration. However, too high concentration of natural compounds affects food sensory and leads to undesired odour, consequently food consumers refuse to consume the packaged foods. Controlled release of the antimicrobials potentially maintains the concentration not going under and over the concentration limit in a longer period. This review gives an overview of the controlled-release mechanisms of various natural compounds in an antimicrobial food packaging. Factors influencing release, absorption and concentration of natural antimicrobial in microbial inhibition are defined in three categories: (1) physical characteristics of antimicrobial-releasing carrier, (2) food structure and properties, (3) external factors. Considering these factors in regulating antimicrobial packaging is discussed comprehensively, so the effectiveness of the packaging in prolonging the food shelf life can be achieved. [ABSTRACT FROM AUTHOR]

A Lamb dip spectroscopic measurement of the Q(1) transition in the (2-0) overtone band of ortho- $ \hbox {H}_2 $ H 2 is performed with the ultra-sensitive NICE-OHMS intracavity absorption technique at $ 1238\,\hbox {nm} $ 1238 nm . For the first time individual hyperfine components of a vibrational transition in $ \hbox {H}_2 $ H 2 are resolved, displaying a pattern of 4 overlapping components with singly isolated components at the red and blue side. Weak components at a line strength of $ 4.4 \times 10^{-28} $ 4.4 × 10 − 28 cm/molecule could be observed as a Lamb dip. Analysis yields a hyperfineless purely rovibrational transition frequency for the Q(1) (2-0) line in $ \hbox {H}_2 $ H 2 at unprecedented accuracy for any rovibrational transition in a molecular hydrogen isotopologue. Its frequency is 242,091,630,140 $ \,(9)\,\hbox {kHz} $ (9) kHz under the assumption that only a blue recoil component is observed. A 1.7σ deviation from the most advanced quantum electrodynamics calculations is obtained, forming a challenge for theory. [ABSTRACT FROM AUTHOR]

AbstractThe growing co-consumption of botanical natural products with conventional medications has intensified the need to understand potential effects on drug safety and efficacy. This review delves into the intricacies of intestinal pharmacokinetic interactions between botanical natural products and drugs, such as alterations in drug solubility, permeability, transporter activity, and enzyme-mediated metabolism. It emphasizes the importance of understanding how drug solubility, dissolution, and osmolality interplay with botanical constituents in the gastrointestinal tract, potentially altering drug absorption and systemic exposure. Unlike reviews that focus primarily on enzyme and transporter mechanisms, this article highlights the lesser known but equally important mechanisms of interaction. Applying the Biopharmaceutics Drug Disposition Classification System (BDDCS) can serve as a framework for predicting and understanding these interactions. Through a comprehensive examination of specific botanical natural products such as byakkokaninjinto, green tea catechins, goldenseal, spinach extract, and quercetin, we illustrate the diversity of these interactions and their dependence on the physicochemical properties of the drug and the botanical constituents involved. This understanding is vital for healthcare professionals to effectively anticipate and manage potential natural product-drug interactions, ensuring optimal patient therapeutic outcomes. By exploring these emerging mechanisms, we aim to broaden the scope of natural product-drug interaction research and encourage comprehensive studies to better elucidate complex mechanisms. [ABSTRACT FROM AUTHOR]

AbstractTheaflavins, a major kind of component in black tea, have been reported to show a variety of biological activities and health effects. However, the unstable chemical properties, low bioavailability and unclear metabolism pathways of theaflavins have left much to be desired in terms of its specific efficacy and applications. This paper provides a comprehensive knowledge on the digestion, absorption, metabolism, distribution and excretion of theaflavins. We find that pH-dependent stability, efflux transport proteins are closely related to the low absorption rate and low bioavailability of theaflavins. When pass through the gastrointestinal tract, TFDG, TF2A and TF2B are gradually degraded to TF1, and release gallic acid. Then, the theaflavins skeleton are degraded into small molecular phenolic substances under the action of enzymes and microorganisms. In addition, theaflavins are widely distributed in the human body including brain, lung, heart, kidney, liver, blood tissue in a low content and can be excreted through feces. However, the influence of digestive enzymes barrier and gut microbial barrier on theaflavins are still unclear. Importantly, most findings are reported by in vitro methods and animal experiments, the metabolites and metabolic pathways of theaflavins in human body are not fully understood and need to be further investigated. We hope to lay a theoretical basis for exploring methods to improve the bioavailability of theaflavins and expanding the application of theaflavins in health foods as well as pharmaceuticals. [ABSTRACT FROM AUTHOR]

\nPlain Language SummaryThe effect of non-ionizing millimeter range electromagnetic waves (MM EMW) (30–300 GHz) on the bovine serum albumin (BSA) interaction peculiarities with acridine orange (AO) has been studied in vitro. The frequencies 41.8 and 50.3 GHz were chosen, since the first one is nonresonant frequency for the water, while the second one is resonant for water. The binding constant and number of binding sites were calculated at both irradiation presence and absence. AO was revealed to bind to BSA, while after the protein irradiation the interaction force strengthens. However, it was also shown that there are differences of the interaction parameters while irradiating by 41.8 or 50.3 GHz. AO binds to BSA, irradiated by MM EMW with the frequency 41.8 GHz much more weaker, than to that, irradiated by MM EMW with the frequency 50.3 GHz.The manuscript is devoted to the study of the effect of millimeter range electromagnetic waves with the frequencies 41.8 and 50.3 GHz on the model biological system, being on molecular level of organization. Nowadays millimeter range electromagnetic waves compose a significant part of electromagnetic pollution in the environment and affect biological material, besides these waves are used in extremely high frequencies-therapy ((30–300 GHz), which are millimeter range electromagnetic waves (1–10 mm)). On the other hand, the problem of their effect mechanism is mainly connected to water, since the resonant frequencies for water molecules are in the interval of millimeter waves. In the present study, as such biological molecule, the bovine serum albumin has been chosen, which interacts with acridine orange. Serum albumins are known to carry and transport various endogenous and exogenous agents, including drugs throughout circulatory system. In turn, acridine orange has been extensively used for biological staining to differentiate DNA from RNA by fluorescence emission for years, Nowadays, it is considered as a promising agent for antitumorous treatment and diagnosis.The data obtained show that the interaction between bovine serum albumin and acridine orange changes, when the solution of albumin is irradiated by the millimeter waves with the frequencies 41.8 and 50.3 GHz. However, the interaction alteration depends on the frequency as well. Thus, the irradiation with the frequency 41.8 GHz makes insignificant changes, while that with the frequency 50.3 GHz induces significant changes of measured parameters. The studies were conducted by absorption, fluorescence and CD spectroscopy methods. [ABSTRACT FROM AUTHOR]

AbstractTo enhance the performance of the six-missing rib honeycomb (ASRH), two axisymmetric missing rib honeycombs, ASRH-1 and ASRH-2, are proposed in this study. First, the in-plane impact performance of ASRH, ASRH-1, and ASRH-2 is experimentally compared to verify the accuracy of the finite element model. Then, the deformation patterns, specific energy absorption (SEA), and negative Poisson’s ratio (NPR) effects of the three honeycombs under different parameters were parametrically investigated. The results indicate that ASRH-1 and ASRH-2 exhibit higher SEA than ASRH at an impact velocity of 10 m/s, but the NPR effect does not change significantly. The axisymmetric honeycomb demonstrates no advantage at 50 and 100 m/s high-speed impacts. The Poisson’s ratio effect of the three honeycombs varied greatly with the internal ligament r of the honeycomb. The axisymmetric design offers a new concept for a NPR honeycomb design. [ABSTRACT FROM AUTHOR]

AbstractHierarchical tubes have been proved to be excellent energy absorbers under axial compression. However, there are limited studies exploring their oblique crushing performance. Therefore, the oblique crushing characteristics of hierarchical tubes, bio-inspired hierarchical multi-cell square tubes (BHMS), hierarchical multi-cell square tubes (HMSA and HMSB), have been numerically studied. The influencing factors of loading angle and hierarchical order on deformation modes, force-displacement curves, and energy absorption (EA) behaviors were explored. It is found that BHMS tubes present the superior crushing performance among these hierarchical square tubes. Moreover, BHMS tubes display the excellent crushing characteristics in comparison with single square tubes. Specifically, the specific EA of BHMS-3 tubes is 213%, 212%, 66%, and 42% greater than that of single square tubes at loading angles of 0°, 10°, 20°, and 30°. The findings demonstrate the priority of hierarchical square tubes under oblique crushing, and provide the reference and insight for the design of energy absorbers. [ABSTRACT FROM AUTHOR]

AbstractA new type of bi-double square gradient hierarchical tube (DSGHT) is proposed, and its crashworthiness under consistent wall thickness is analyzed. The results show that the energy absorption (EA), specific energy absorption (SEA), and crush force efficiency (CFE) of DSGHT3 are increased by 1305.14%, 430.14%, and 469.50%, respectively, compared to DSGHT0. The combination of double square tubes and gradient laminar design effectively enhances the crashworthiness of the structure. A parametric study indicates that increasing wall thickness significantly improves crashworthiness, with EA, SEA, and CFE improvements of 805.75%, 125.83%, and 126.83%, respectively, at a wall thickness of 0.8 mm compared to 0.2 mm. However, the effect of wall thickness gradient distribution on structural crashworthiness is minimal. Conversely, the ratio of the inner to outer square tube edge length (δ) significantly impacts crashworthiness; SEA and CFE increase by 37.77% and 37.35%, respectively, when δ is 6/12 compared to 8/12. Finally, DSGHT3 was compared to other hierarchical, tree-shaped fractal structures, and it demonstrated superior crashworthiness. Specifically, DSGHT3 has 35.32% and 34.29% higher SEA and CFE, respectively, compared with MSTL2-2. [ABSTRACT FROM AUTHOR]

The work of 1930s writers Antonin Artaud, Stanley Weinbaum, and Max Herrmann, reveals an early history of Virtual Reality and a burgeoning interest in how the virtual can be concretized through experiences requiring the complicity of willing participants within a live performance setting. This sheds light on techniques underlying, and potentially overlooked, in contemporary illusory practices modifying perceptions of reality through the related terms that developed over the century, including ‘self-hypnosis,’ ‘creative work,’ ‘consensual hallucination,’ and ‘metaxis’. The paper speculates that the prerequisite for immersive technologies to function is the concretization of the virtual in the participant’s body achieved through complicity, suspension of disbelief, and absorption. This line of inquiry begins to connect with Karen Barad’s agential realism through mattering, specifically with the computational and virtual, which seem not to matter and are too often overlooked as immaterial. It proceeds through three sections exploring the purported modifiers of reality (especially X-Reality, Extended Reality, and Mixed Reality), how performance brings the virtual to matter, and testing these ideas through a case study, the immersive VR/MR/XR artwork Child of Now staged in Melbourne in 2022. [ABSTRACT FROM AUTHOR]

Epigallocatechin gallate (EGCG), a typical flavone-3-ol polyphenol containing eight free hydroxyl groups, is associated with a variety of bioactivities, such as antioxidant, anti-inflammatory, anti-cancer, and antibacterial activities. However, the poor bioavailability of EGCG restricts its use. In this review, we discuss the processes involved in the absorption and metabolism of EGCG, with a focus on its metabolic interactions with the gut microbiota. Next, we summarize the bioactivities of some key metabolites, describe the biotransformation of EGCG by different microorganisms, and discuss its catabolism by specific bacteria. A deeper understanding of the absorption, metabolism, and biotransformation of EGCG may enable its disease-preventive and therapeutic properties to be better utilized. This review provides a theoretical basis for further development and utilization of EGCG and its metabolites for improving the gut microbiota and physiological health. [ABSTRACT FROM AUTHOR]

AbstractThis study aims to investigate the crashworthiness performance of a novel hierarchical multi-cell double circular tubes (HMDC) structure under axial impact. Various dual-tube structures of different cross-sections were designed. The effects of hierarchical order, peak number of the core column, and inner circle diameter on the structure were analyzed using Abaqus finite element analysis. The results indicate that in dual-tube structures, replacing the traditional multi-cell structure with a hierarchical multi-cell structure in the interlayer significantly improves energy absorption (EA) characteristics. With the inner circle diameter of the HMDC fixed at 20 mm, the ratio of mean crushing force (MCF) to peak crushing force at the third order increased by 70.70% and 35.68% compared to the first and second orders, respectively. Experimental results and finite element results show that the initial peak value differed by 1.47%, indicating a close match between the experimental and simulation results. The parametric study shows that the inner circle diameter and the peak number of the core column significantly affect EA. The findings of this study provide effective guidance for designing multi-cell dual circular tubes with high EA efficiency. [ABSTRACT FROM AUTHOR]

To achieve the goals of high energy dissipation, a low initial peak, and small load fluctuation, a differentiated combination design of multitube combined structure was developed. Based on a combination of experiment, simulation, and theory, the influences of height and fold distribution on the peak-formation time sequence were investigated, and the combined method of two configurations in the multitube combination was determined. The results show that the initial peak and load fluctuation of the combined structure with variable tube heights and different fold distributions are reduced by 18.42% and 67.77%, respectively, compared with the multitube structure of the same configuration. [ABSTRACT FROM AUTHOR]

The present study aims to assess a new lattice structure with high energy absorption capacity. Lattice structures with surface-based unit cell have higher energy absorption than those with strut-based unit cell. A new lattice structure is presented by adding the strut to the surface-based unit cell which has a higher energy absorption capacity than the lattice structures with surface-based unit cell. First, the high energy absorption capacity of surface-based lattice structures was evaluated by adding the strut. Such analyzes are conducted by providing a numerical model which considers the elasto-plasto-damage properties of materials under tension and compression. Then, a number of experimental samples were made using additive manufacturing and the compression test was performed. The results of finite element analysis were consistent with those of the experimental results. Based on the results, adding strut increased the energy absorption for surface-based lattice structures by about 106%. Finally, the effect of the ratio of geometric parameters of the unit cell on its mechanical behavior was evaluated. [ABSTRACT FROM AUTHOR]

In this work, we report a series of stretching-dominated plate-based mechanical metamaterials to simultaneously achieve vibration insulation and energy absorption. The performances of vibration insulation and energy absorption of these mechanical metamaterials are synthetically compared. The optimal mechanical metamaterial, namely S8, is extracted from all relevant mechanical metamaterials by the complex proportional assessment (COPRAS) method. Additionally, parametric studies of the S8 are performed to reveal the effect of structural parameters on the performances of vibration insulation and energy absorption. Finally, multi-objective optimization of the S8 is implemented to obtain the Pareto front. Findings from this work can provide effective guidance for the design of mechanical metamaterials with simultaneous vibration insulation and energy absorption. [ABSTRACT FROM AUTHOR]

Hierarchical design and gradient design have proven to be effective in improving the crashworthiness of honeycombs. In this study, a novel graded hierarchical hexagonal honeycomb (GHHH) is proposed by introducing wall thickness variation into the vertex-based hierarchical hexagonal honeycomb (VHHH). The VHHH is obtained by replacing every vertex of the regular hexagonal honeycomb (RHH) with a smaller hexagon. Numerical simulations and theoretical analysis are performed to study the crashworthiness performance of GHHH under the out-of-plane impact. The numerical results show that the specific energy absorption (SEA) of GHHH can be 146.09%, 39.01%, and 50.23% higher than that of RHH, VHHH, and graded hexagonal honeycomb (GHH), respectively, while their peak stresses are nearly the same. In addition, a theoretical model for the plateau stress of GHHH is developed, and the theoretical values show good consistency with numerical results of GHHH with in-extensional mode. The findings of this study provide an effective guideline for the design of honeycombs with enhanced crashworthiness. [ABSTRACT FROM AUTHOR]

Inspired by the tree fractal structure, a novel hexagonal hierarchical gradient tube with axial variable thickness (HHGAVT) is proposed and its crashworthiness performances are systematically investigated. Results show that when the axial variation coefficient of wall thickness k > 0, the peak crushing force (PCF) of HHGAVT will significantly decrease meanwhile the energy absorption maintains at a high level compared with the referenced structures under the same mass. When k > 0, the PCF and CFE of HHGAVT have absolute advantage compared with the uniform wall thickness tube. The crashworthiness performance can further increase by rational designing the distance factor δ. [ABSTRACT FROM AUTHOR]

Based on the conventional star-shaped tube, a star-shaped multicellular tube was proposed and designed; finite element modeling was carried out using Abaqus/Explicit software, and the accuracy of the finite element model was verified under axial impact, the crashworthiness study shows that the star-shaped multicellular tube is significantly improved compared to the conventional star-shaped tube for the same wall thickness and same mass conditions. Namely, for the same wall thickness conditions, the energy absorption of the star-shaped quadrangular multicellular tube (SSMT-4-140°) is 1.77 times that of the star-shaped quadrangular tube (SST-4-140°), and the crush force efficiency is 1.24 times that of SST-4-140°; at the same mass, the energy absorption of SSMT-4-140° is 1.17 times that of SST-4-140°, and the crush force efficiency is 1.14 times that of SST-4-140°. Subsequently, the parametric study of the number of corners N, angle between two adjacent corners θ°, and wall thickness on the star-shaped multicellular tube was systematically carried out. The results of this paper can provide valuable information toward the innovative design of multicell tube structures. [ABSTRACT FROM AUTHOR]

It is still a challenge to achieve perfect ((near-unity)) absorption across a wide wavelength range with a three-layer structure. This paper presents a metamaterial absorber (MA) based on MXene that can achieve broadband and perfect absorption in the near-infrared and visible regions. The MA with a simple three-layer structure consists of a top Ti3C2Tx layer, an intermediate dielectric layer and a bottom gold layer. It can achieve perfect absorption (the absorptivity over 99%) in the wavelength range of 730–900 nm. The electric field distribution reveals that the localized surface plasmon resonance occurring at the interface of Ti3C2Tx and SiO2 leads to strong absorption over the wide wavelength range. Furthermore, the MA exhibits excellent angular stability. This work provides a method to construct MAs with broadband perfect absorption in the near-infrared and visible band. [ABSTRACT FROM AUTHOR]

Recently, auxetic honeycombs have attracted widespread attention with characteristics of lightweight, excellent energy absorption capacity and high shear stiffness. The present paper proposes the hybrid star-shaped tetra-chiral honeycomb (STCH) by embedding the tetra-chiral honeycomb (TCH) into the star-shaped honeycomb (SSH). The deformation mode and compression behavior of the STCH were studied numerically and compared with that of the SSH and TCH. Particularly, under the impact velocity of 2 m/s, the specific energy absorption (SEA) of the STCH increases by 80 and 179% than that of the SSH and TCH, respectively. Through investigating the effect of impact velocity and relative density on the crushing behavior of the STCH, the deformation modes map was summarized, and the empirical formula of the plateau stress was presented. Subsequently, the detailed parameter analysis of the STCH revealed that in a certain range, the SEA and stability of the STCH increase with the increase of N x , θ , and R , and with the decrease of L 2 and L 1. Finally, the improved STCH (ISTCH) with stable deformation and better crashworthiness was further proposed, and the crashworthiness of it was comprehensively compared with other structures. The result shows the excellent crashworthiness of the ISTCH. Particularly, the SEA of ISTCH can be nearly 8 times higher than that of the TCH. The novel star-shaped tetra-chiral honeycomb (STCH) can absorb more energy due to the increase of plastic hinges and the complex coupling deformation. The deformation modes map of the STCH was summarized and the plateau stress was fitted. The change of radius and cell wall angle can greatly change the Poisson's ratio from positive to negative. The STCH and improved STCH have excellent crashworthiness. [ABSTRACT FROM AUTHOR]

In order to improve the crashworthiness of traditional Thin-Walled Struct, a new method for designing multicellular tubes is presented in this paper. In this work, multicellular columns based on origami centripetal folding method (MCOCFM) are proposed. The cross section of MCOCFM is designed in the way of origami. The mechanical properties of MCOCFM under uniaxial compression are analyzed by numerical simulation. Studies have shown that increased levels and wall thickness facilitate energy absorption. In addition, the theoretical prediction of MCF is in good agreement with the simulation results. Compared with some existing structures, MCOCFM has better crashworthiness. [ABSTRACT FROM AUTHOR]

The diffusion and wide application of green technologies are important means to achieve climate change mitigation. Concerning the green technology absorption capacity and technology diffusion willingness of enterprises, this paper divided enterprises into four categories, constructed a green technology diffusion model and analysed the equilibrium point and stability of the model. Then, we studied the diffusion process and laws of green technology through simulation experiments. The results show that in the green technology diffusion system, the basic regeneration number is the key factor in determining the equilibrium state of green technology diffusion. The disease-free equilibrium point of the green technology diffusion system is globally asymptotically stable, and the endemic equilibrium point is locally asymptotically stable. In order to improve the speed and scale of green technology diffusion, it is necessary to create green technology diffusion sources through multiple channels, improve enterprise technology absorption capacity through multiple methods, and enhance enterprise green technology diffusion willingness at multiple levels. [ABSTRACT FROM AUTHOR]

Fiber-reinforced composite tubes have remarkable advantages in energy absorption due to the high specific strength, stiffness, and fracture energy, etc. While, the energy absorption capacity is severely dominated by buckling deformation. To this end, the buckling behaviors and corresponding mechanism of CFRP (carbon fiber reinforced polymer) tubes are systematically investigated in this work. Furthermore, an advanced bionic method referring to bamboo and human bones is adopted to improve the buckling. To effectively analyze the buckling, drop weight impact experiments and corresponding numerical simulations are carried out. The results show that the specific energy absorption (SEA) of CFRP tubes is significantly affected by the diameter-to-height ratio and fiber ply direction, and the influencing mechanism is excessive buckling caused by the geometric characteristics and brittle failure of CFRP. At last, the SEA of CFRP tubes were improved through bio-inspired multi-layered metal/composite hybrid, where the buckling is suppressed reasonably well. The conclusions drawn would be inspiring or guiding the optimal design of high energy-absorbing composite tubes in engineering application. [ABSTRACT FROM AUTHOR]

Honeycomb structures have attracted wide attention due to outstanding mechanical properties as promising light material structures. Inspired by nature and artistic design, various honeycombs with different microstructural configurations have been designed for the sake of better mechanical performances and functions. Here, the Miura-origami reentrant honeycomb (MRH) structure integrating reentrant honeycombs (RH) and Miura-origami structures is investigated systematically. Dynamic impact behaviors of the present MRH structure are investigated numerically. The deformation modes and energy absorption capacity of RH and MRH are compared under different impact velocities, including low-velocity, medium-velocity and high-velocity. The results show that the plateau stress and the specific energy absorption(SEA) of MRH is much higher than RH. Moreover, the parametric study indicates that raising the inclined angle will decrease the plateau stress and the absolute value of Poisson'ratio for MRH structures. The specific energy absorption curves increase as the inclined angle of MRH grows up. In addition, the MRH with smaller dihedral angle can absorb much more impact energy and the variation of absorbed energy is proportional to the cell wall thickness of the MRH structure. This work is expected to provide a new thought for designing advanced energy absorption metastructures and achieving superior mechanical performances. [ABSTRACT FROM AUTHOR]

This study analyzes the behavior of CFRP tape laminates under high-velocity impact when they are subjected to in-plane tensile preload. Experimental tests were carried out using a gas-gun setup in non-loaded and preloaded laminates. Impact and residual velocities were measured, the ballistic limit and damage area were estimated, and it was observed that the ballistic limit was lower in preloaded specimens. An analytical model was developed and validated. Some differences were observed in terms of energy absorption mechanism distribution between preloaded and non-loaded laminates for impact velocities close to the ballistic limit. The influence on the ballistic limit with the preload level was studied. [ABSTRACT FROM AUTHOR]

Portion of energy employed by a single, tightly focused laser pulse in various transparent dielectrics was demonstrated versus the incident energy fluence or alternatively, intensity. The measurements were conducted for both the femtosecond and nanosecond laser pulses. Moreover, the energy scattered during the long-lived breakdown process was estimated within the integrating sphere. It appeared that the recorded strongly non-linear dependence of absorptance on the energy fluence (intensity) can be well approximated by the sigmoidal Hill function. The stationary points of the absorptance curve were used to determine threshold-like values characterizing breakdown development. In this way, we defined threshold for the non-linear absorption which can be considered as an empirical laser-induced breakdown threshold (LIBT). Additionally, the fitting parameters of the experimental data substantiated the absorption character for short and long laser pulses. [ABSTRACT FROM AUTHOR]

As a vitro absorption model, the Caco-2 cells originate from a human colon adenocarcinomas and can differentiate into a cell layer with enterocyte-like features. The Caco-2 cell model is popularly applied to explore drug transport mechanisms, to evaluate the permeability of drug and to predict the absorption of drugs or bioactive substances in the gut. However, there are limitations to the application of Caco-2 cell model due to lack of a mucus layer, the long culture period and the inability to accurately simulate the intestinal environment. The most frequent way to expand the Caco-2 cell model and address its limitations is by co-culturing it with other cells or substances. This article reviews the culture methods and applications of 3D and 2D co-culture cell models established around Caco-2 cells. It also concludes with a summary of model strengths and weaknesses. [ABSTRACT FROM AUTHOR]

This research deals with the improvement in the mechanical properties of pavement quality concrete (PQC) when mixed with Class-F Fly-Ash (FA) and Copper Slag (CS) as replacements for ordinary Portland cement (OPC) and river sand (RS), respectively. Forty-eight different PQC mixes of M40 and M50 grades were prepared, in which RS is replaced by CS to the extent of 100%, and OPC is replaced by FA to the extent of 30%, with each replacement done at a certain increment. The combined effects of CS and FA on fresh and hardened concrete properties such as workability, density, water absorption, volume of voids, cube compressive strength, split tensile strength, flexural strength, cylinder compressive strength and ultrasonic pulse velocity (UPV) are experimentally investigated. All mixes containing up to 20% FA and up to 100% CS replacements showed increased strength compared with that of the control mix. The PQC mix containing 20% FA and 60% CS resulted in superior strength properties at a 90-day curing period. However, PQC mixes with 30% FA showed a decrease in strength properties with respect to the control mix. X-ray diffraction (XRD) and scanning electron microscope (SEM) studies were employed for the characterisation of selected PQC samples. Furthermore, multiple linear regression equations were established to predict all the strength parameters. The PQC mixes made with FA and CS provide superior strength, reduce waste disposal problems and preserve natural resources for future generations, making such developed mixes sustainable. [ABSTRACT FROM AUTHOR]

This paper aimed to investigate the effect of Nano-TiO2 as a semi-conductor additive on the pollutant's absorption of a micro-surfacing layer. In this research, micro-surfacing samples with Nano-TiO2 values of 5, 7, 9, 11, and 13% (by weight of bitumen) and two types of aggregates (immersed and non-immersed aggregates in Nano-TiO2) were tested to determine contaminant absorption and evaluate rutting performance at two temperatures of 20 and 40°C. The results revealed that NOX absorption improved with increasing Nano-TiO2, reaching 40% in samples with the optimal amount of Nano-TiO2 (11% by weight of bitumen). Wheel track test results showed that the optimum sample had a better performance compared to the control sample. Also, it was observed that the absorption of pollutants decreased after conducting the wheel track test. [ABSTRACT FROM AUTHOR]

Unequal spatial concentration is at the heart of economic imbalance in South Africa. This research aimed at spatially characterizing labor absorption patterns and exploring the link to spatial development. Labor absorption is often used as an indicator of labor market well-being and for many countries, the indicator is often more insightful than the unemployment rate. The research used secondary data to create a longitudinal data set of labor absorption, functional literacy, the ratio of urban population and gross domestic product growth rate, among others, at a municipal level. Exploratory spatial data analysis and thematic mapping were undertaken to illustrate the characteristics of the labor market, while spatial grouping created clusters of municipalities based on labor absorption. A positive upward trend was observed between labor absorption and the share of people in an urban area; that is, the more urban an area, the higher the labor absorption rate. Furthermore, the spatial clustering of municipalities highlighted linear patterns and when this was overlayed with roads and development corridors, clearly indicated the impact of regional spillovers. The findings suggest a more integrated focus on regional innovation policy to reduce spatial disparities in the economic landscape. [ABSTRACT FROM AUTHOR]

The basic principle for the treatment of idiopathic diarrhoea (functional diarrhoea K59.1) is to delay transit through the gut in order to promote the absorption of electrolytes and water. Under mild conditions, bulking agents may suffice. With increasing severity, antidiarrhoeal pharmaceuticals may be added in a stepwise manner. In diarrhoea of unknown aetiology, peripherally-acting opioid receptor agonists, such as loperamide, are first-line treatment and forms the pharmaceutical basis of antidiarrheal treatment. As second-line treatment opium drops have an approved indication for severe diarrhoea when other treatment options fail. Beyond this, various treatment options are built on experience with more advanced treatments using clonidine, octreotide, as well as GLP-1 and GLP-2 analogs which require specialist knowledge the field. Chronic diarrhoea without an established cause is common. There are a small number of clinical trials, often with a limited number of patients or healthy volunteers. Treatment is often carried out on a trial-and-error basis, with considerable variation in the choice of treatment. There is a paucity of guidelines, and there is a gap in knowledge concerning treatment goals, such as the frequency, consistency and form of stool. The stepwise approach to the treatment of chronic idiopathic diarrhoea described in this article is based on clinical knowledge and experience. [ABSTRACT FROM AUTHOR]

Most autobiographical memories are based on real-life experiences, but memories of fiction have many similarities to real-life autobiographical memories. However, the phenomenological nature of this similarity, the potential differences between media types, and the role of individual differences need further investigation. Based on previous findings, we expected differences between media types on emotional intensity, sensory vividness, and confidence about the recall. To provide insight into these issues, we collected one real-life autobiographical memory and one memory of fiction (book, film, or video game) from 291 participants. We asked them to rate their memories phenomenologically. The participants also provided information regarding their motivations for engaging with fictional stories. Our results show phenomenological differences in several dimensions between media types and differences in the similarity of media types to real-life memories. While absorption seems to be a good predictor for immersion, escapism tendency is a motivation to engage with fiction frequently. [ABSTRACT FROM AUTHOR]

Proanthocyanidins, widespread in natural plant sources, are bioactive substances that exhibit broad benefits to human health. Of note, proanthocyanidins have been reported to lower blood pressure and prevent hypertension, but a critical review of this is lacking. In this review, information on the basic structures and absorption of dietary proanthocyanidins as well as their bioactivities and related mechanisms on the lowering of blood pressure derived via in vivo and clinical studies are summarized. Clinical studies have shown that proanthocyanidins have a pronounced blood pressure-lowering effect, effectively preventing hypertension and reducing the occurrence of cardiovascular and cerebrovascular diseases. The potential mechanisms, which are herein reviewed in detail, involve the improvement of vascular function, reduction of oxidative stress and inflammation, and modulation of lipid metabolism. Taken together, this work provides information for a better understanding of the antihypertensive effects of proanthocyanidins, which may promote their use to reduce the risk of developing hypertension. [ABSTRACT FROM AUTHOR]

AbstractTo realize the safe disposal of solid waste containing heavy metals, sewage sludge jointly with slag and metakaolin was used to prepare alkali-activated materials (AAMs), and the effect mechanism of polycarboxylate acid superplasticizer (PCE), naphthalene superplasticizer (NS) and aliphatic superplasticizer (AS) in AAMs were studied. The results showed that both the fluidity and strength of AAMs decreased with the addition of sludge. For the NaOH + Na2SiO3 activated mortar specimen, the incorporation of sludge can reduce their fluidity and strength from 206 mm and 80.25 MPa to 193 mm and 42.43 MPa, respectively. However, the addition of superplasticizers into sludge-containing AAMs leads to a reduction of 3–9% of the fluidity. Interestingly, it can enhance the strength of the AAMs, especially the NS and AS, which increase the strength by approximately 25%. This is attributed to the increase of particle dispersion by superplasticizers. However, the free water released in the process is reabsorbed by the sludge, which increases the local alkali concentration and promotes the activation of the activity. The dispersed sludge particles can play the role of physical filling, making the structure denser. HIGHLIGHTSSludge is adverse effects on both the fluidity and strength of alkali-activated materials (AAMs).The addition of superplasticizers (SPs) increases the strength of AAM with sludge.SPs do not affect improving the fluidity of AAMs with sludge, even slightly bad.The dispersion effect of SPs on the sludge is beneficial to promote its activity in AAMs.Sludge is adverse effects on both the fluidity and strength of alkali-activated materials (AAMs).The addition of superplasticizers (SPs) increases the strength of AAM with sludge.SPs do not affect improving the fluidity of AAMs with sludge, even slightly bad.The dispersion effect of SPs on the sludge is beneficial to promote its activity in AAMs. [ABSTRACT FROM AUTHOR]

Auxetic structures possess high energy absorption, especially under impact loads that are influenced by their negative Poisson's ratio (NPR). This negative ratio is due to their specific microstructural designs. In this article, newly modified designs for an existing chiral auxetic structure have been proposed and their mechanical and energy absorption performances have been investigated. In the proposed designs, the geometry of slots in an available peanut-shaped auxetic structure has been modified and some extra masses have been removed to introduce innovative auxetic structures with higher NPRs, higher energy absorption, and lower structural weight. By performing finite element simulations in ABAQUS software, it has been found that the proposed modifications in the design of the available auxetic structure result in up to 7.3% and 76.6% increases in Poisson's ratio and energy absorption respectively. The accuracy of simulations has also been confirmed by performing a comparison study with some available results of experimental tests. [ABSTRACT FROM AUTHOR]

CO2 capture experiments were carried out in a small-scale bubble column reactor using alkaline solutions of sodium hydroxide. The results of the experiments show that a higher NaOH content in the liquid phase and elevated CO2 concentrations in the gas mixture led to a higher CO2 removal efficiency. A mathematical model was developed to describe the CO2 absorption as a function of CO2 gas inlet and OH- concentrations at low CO2 and OH- concentrations. The CO2 uptake at high OH- concentrations (high pH) was accurately predicted by the model, whereas the CO2 uptake at lower OH- concentrations could not be predicted with the same accuracy. [ABSTRACT FROM AUTHOR]