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OBJECTIVE: Prediabetes in young people is an emerging epidemic that disproportionately impacts Hispanic populations. We aimed to develop a metabolite-based prediction model for prediabetes in young people with overweight/obesity at risk for type 2 diabetes. RESEARCH DESIGN AND METHODS: In independent, prospective cohorts of Hispanic youth (discovery; n = 143 without baseline prediabetes) and predominately Hispanic young adults (validation; n = 56 without baseline prediabetes), we assessed prediabetes via 2-h oral glucose tolerance tests. Baseline metabolite levels were measured in plasma from a 2-h postglucose challenge. In the discovery cohort, least absolute shrinkage and selection operator regression with a stability selection procedure was used to identify robust predictive metabolites for prediabetes. Predictive performance was evaluated in the discovery and validation cohorts using logistic regression. RESULTS: Two metabolites (allylphenol sulfate and caprylic acid) were found to predict prediabetes beyond known risk factors, including sex, BMI, age, ethnicity, fasting/2-h glucose, total cholesterol, and triglycerides. In the discovery cohort, the area under the receiver operator characteristic curve (AUC) of the model with metabolites and known risk factors was 0.80 (95% CI 0.72–0.87), which was higher than the risk factor-only model (AUC 0.63 [0.53–0.73]; P = 0.001). When the predictive models developed in the discovery cohort were applied to the replication cohort, the model with metabolites and risk factors predicted prediabetes more accurately (AUC 0.70 [95% CI 40.55–0.86]) than the same model without metabolites (AUC 0.62 [0.46–0.79]). CONCLUSIONS: Metabolite profiles may help improve prediabetes prediction compared with traditional risk factors. Findings suggest that medium-chain fatty acids and phytochemicals are early indicators of prediabetes in high-risk youth. [ABSTRACT FROM AUTHOR]

• Biochar-amended soils as intermediate covers mitigates acid accumulation. • Biochar-amended soils as intermediate and final covers increases CH 4 yield by 25%. • Biochar-amended soils as intermediate covers enhances decomposition of MSWs. • Biochar-amended soils as landfill covers reduces ammonia accumulation. The effects of biochar-amended soils as landfill covers have been extensively studied in terms of liquid and gas permeability. However, the influences of biochar-amended soils on the performance of municipal solid wastes (MSWs) in bioreactor landfills have not been well understood. This paper investigates the potential application of biochar-amended soils as final and intermediate covers in landfills. The MSWs with biochar-amended soils as final and intermediate covers were recirculated with mature leachate in laboratory-scale bioreactors. The pH, chemical oxygen demand, ammonia and volatile fatty acids (VFAs) concentrations of leachates, mass reduction rates, settlement, methane, and total gas generations of MSWs were investigated. The results indicate that biochar-amended soils as intermediate landfill covers can provide pH-buffer capacity, increase the pH of leachate and decrease the accumulation of VFAs in the early stage of decomposition. The concentration of ammonia in the leachate with biochar-amended soils as intermediate cover is lower than that with natural soils. The application of biochar-amended soils as intermediate and/or final covers increases the biocompression ratios and settlement of MSWs. The application of biochar-amended soils as final cover slightly decreases the methane generation potential (L 0). Biochar-amended soils as intermediate covers increase L 0 by 10%, and biochar-amended soils as both intermediate and final covers enhance L 0 by 25%. The increase in the ammonia removal, settlement, and methane yield indicates the viability of biochar-amended soils as intermediate landfill covers. Further studies can focus on the long-term behaviour of MSWs with soil covers with different biochar amendment rates and particle sizes. [ABSTRACT FROM AUTHOR]

Per- and poly-fluorinated compounds (PFAS) and heavy metals constitute two classes of environmental exposures with known immunotoxicant effects. In this pilot study, we aimed to evaluate the impact of exposure to heavy metals and PFAS on COVID-19 severity. We hypothesized that elevated plasma-PFAS concentrations and urinary heavy metal concentrations would be associated with increased odds of ICU admission in COVID-19 hospitalized individuals. Using the University of Southern California Clinical Translational Sciences Institute (SC-CTSI) biorepository of hospitalized COVID-19 patients, urinary concentrations of 15 heavy metals and urinary creatinine were measured in n = 101 patients and plasma concentrations of 13 PFAS were measured in n = 126 patients. COVID-19 severity was determined based on whether a patient was admitted to the ICU during hospitalization. Associations of metals and PFAS with ICU admission were assessed using logistic regression models, controlling for age, sex, ethnicity, smoking status, and for metals, urinary dilution. The average age of patients was 55 ± 14.2 years. Among SC-CTSI participants with urinary measurement of heavy metals and blood measures of PFAS, 54.5% (n = 61) and 54.8% (n = 80) were admitted to the ICU, respectively. For heavy metals, we observed higher levels of Cd, Cr, and Cu in ICU patients. The strongest associations were with Cadmium (Cd). After accounting for covariates, each 1 SD increase in Cd resulted in a 2.00 (95% CI: 1.10–3.60; p = 0.03) times higher odds of admission to the ICU. When including only Hispanic or Latino participants, the effect estimates between cadmium and ICU admission remained similar. Results for PFAS were less consistent, with perfluorodecanesulfonic acid (PFDS) exhibiting a positive but non-significant association with ICU admission (Odds ratio, 95% CI: 1.50, 0.97–2.20) and perfluorodecanoic acid (PFDA) exhibiting a negative association with ICU admission (0.53, 0.31–0.88). This study supports the hypothesis that environmental exposures may impact COVID-19 severity. • COVID-19 has become an endemic disease, impacting millions per year. • In the United States, COVID-19 disproportionately impacts Hispanic populations. • In this population, urinary cadmium was linked to more severe COVID-19 outcomes. • Plasma PFAS had less consistent associations with COVID-19 severity. • Decreasing cadmium exposure may help reduce health disparities of COVID-19. [ABSTRACT FROM AUTHOR]

Microplastic (MP) can significantly affect soil behaviour and the ecosystem. This paper presents an experimental study to investigate the effects of MP contamination and leachate exposure on the desiccation cracks, hydraulic conductivity, and water retention properties of the natural black clay. The leachate was from a landfill in Australia. The black clay was incorporated with up to 2.0% MPs by weight (w/w) with diverse dimensions and mixed with water/leachate. The measured properties include saturated hydraulic conductivity (k sat), soil-water characteristic curves, moisture evaporation rates, and crack intensity factors. The results suggest that the inclusion of MPs significantly increases k sat , and this increase is more obvious for soils with larger dimensions and contents of MPs, e.g., k sat of the black clay with 2.0% of 500 μm MP increases significantly by 206% (p < 0.05). The black clay exposed to leachate exhibits a slight increase in k sat due to the low viscosity of leachate. The existence of MPs decreases the residual moisture contents and air-entry pressures, and so does the water retention capacity (v/v %) of the black clay. The exposure to leachate increases the air-entry pressures by 6.0%–15.8% of the clay. The evaporation rates increase with the dimensions and concentrations of MPs. The highest evaporation rate (0.96 g/h) can be observed in samples exposed to 2.0% 500 μm MP with water addition. For all samples, the crack intensity factors increase when MP content is between 0.2% and 1.0% and decreases slightly after that. After being exposed to leachate, the evaporation rates and crack intensity factors of the black clay are decreased by 2.4%–12.6% and 3.6%–13.7%, respectively. • Contamination of MPs increases the saturated hydraulic conductivity of clays. • Mature leachate does not significantly affect permeability or flow channel of clays. • MPs affect residual moisture contents and air-entry pressure of clays. • Existence of MPs affects the evaporation rate and desiccation crack of clays. • Leachate affects air-entry pressure, evaporation rate, and crack intensity of clays. [ABSTRACT FROM AUTHOR]

Introduction: Lupus mesenteric vasculitis (LMV) is a rare but potentially life-threatening clinical entity in systemic lupus erythematosus (SLE) patients. Objective: The present study was initiated to explore the clinical features and associated factors of LMV in SLE patients. Methods: We conducted a retrospective study on 50 cases of SLE patients with lupus mesenteric vasculitis (LMV) from January 2010 to December 2019 and 89 cases of non-LMV-SLE patients with similar demographic and comorbidities were included as control. All the data regarding clinical features, laboratory findings, and treatment were reviewed independently by two experts in the field. Both univariate and multivariate logistic regression analyses were employed to identify the associated factors of LMV. Results: The incidence of LMV was 2.9% among hospitalized SLE patients in the current study. The most frequent symptom and physical sign of LMV were respectively abdominal pain (48, 96%) and abdominal tenderness (45, 90%). Through univariate and subsequent multivariate analysis, oral ulcer (OR, 4.25; P = 0.024), urinary tract involvement (OR, 5.23; P = 0.021), and elevated D-dimer (OR, 1.121; P = 0.008) were demonstrated to be positively associated with LMV, while percentage of lymphocytes (OR, 0.928; P = 0.004) and complement 3 (OR, 0.048; P = 0.008) were negatively correlated with LMV. Conclusions: Oral ulcer, urinary tract involvement, reduced percentage of lymphocytes and complement 3, elevated D-dimer could be associated factors for LMV in SLE patients. [ABSTRACT FROM AUTHOR]

• Key developments in dynamic testing techniques of yarns and fabrics are summarized. • Gripping fibers effectively is essential in dynamic tensile tests. • The morphology of a yarn affects its transverse deformation behavior. • Polymer spray coating is a method for improving fabric penetration resistance. • Current challenges and future research directions are discussed. This mini review provides a succinct overview of dynamic mechanical tests for woven fabrics and ballistic fibers, which are widely used for penetration-resistant applications. Considering the structural hierarchy of woven fabrics, this work highlights recent studies at different scales, encompassing uniaxial tensile tests and transverse impact tests of yarns, yarn pull-out tests from fabrics, and transverse impact tests of fabrics. The dynamic characterization techniques employed in these tests are discussed, along with the associated challenges. This paper serves as a quick guide for those seeking to gain insights into the dynamic behavior of woven fabrics. [ABSTRACT FROM AUTHOR]

This paper presents the details of experimental work on characterising the tensile properties of UHMWPE (Spectra® 1000) single yarns at different strain rates from 3.3 × 10−5 to 400/s. According to the measured stress–strain curves, there was a transition from ductile to brittle behaviour as the strain rate increased from 3.3 × 10−5 to 0.33/s; the tensile properties were highly sensitive to strain rate in this range. Specifically, the tensile strength and Young's modulus increased distinctly with increasing strain rate while the failure strain and toughness decreased. However, these tensile properties were not dependent on strain rate over the range from 0.33 to 400/s. The results showed that the measured tensile strength, failure strain and Young's modulus were independent of the tested gauge lengths (25 and 50 mm). Moreover, yarn type (warp and weft) had a noticeable effect on tensile strength, but the effect of yarn type on failure strain and Young's modulus was negligible. The microscopic examination of fractured fibres' ends revealed that fibrillation and axial splitting were the dominant fracture modes at low strain rates, while the fibres failed in a more brittle manner with little fibrillation at high strain rates. [ABSTRACT FROM AUTHOR]

This paper reports a method to construct the complete constitutive model of carbon fiber‐reinforced plastic (CFRP) by distinguishing the strain rate state and modifying the material stiffness. In quasistatic (low strain rate) compression, the initial nonlinear effect caused by the material defects was described by introducing an nonlinear increasing factor. In dynamic (high strain rate) impact, the nonlinear strengthening effect was described by introducing the dynamic amplification factors of stress and strain based on the reference state. Considering the instantaneous temperature rise obtained from the impact work–temperature generation equation and the influence of temperature on modulus and strength, the coupled thermomechanical constitutive models combining the strain rate effect and the temperature effect were established. The user‐defined material subroutines (VUMAT) were developed, and then these constitutive models were verified by finite element analysis (FEA). Finally, the developed material subroutine was applied to predict the impact penetration of CFRP laminates, and the results show that the opening holes, damage and energy dissipation are in good agreement with the reference experiment. This work comprehensively analyzed the construction method of CFRP constitutive models, which would provide a guidance for the coupled thermomechanical behavior under dynamic impact. Highlights: An anisotropic continuum mechanical constitutive behavior considering strain rate effect and damage evolution behavior was established.A macroscopic anisotropic constitutive model including the coupled impact temperature generation‐mechanical behavior was established.Combined with the incremental finite element method, the three‐dimensional user‐defined material subroutines (VUMAT) were developed and verified.The thermomechanical impact penetration behaviors of CFRP laminates was predicted, and the stress field, temperature field and failure characteristics were visualized. [ABSTRACT FROM AUTHOR]

An important factor for the prognosis of spinal surgery is the perioperative use of opioids. However, the relationship is not clear. The purpose of this study was to evaluate the effect of perioperative opioid use on the prognosis of patients following spinal surgery. Systematic review and meta-analysis. A meta-analysis was conducted using the random-effects method to calculate pooled odds ratios (ORs) with 95% confidence intervals (CIs). The PubMed, Embase, and Cochrane Library databases were systematically searched to find relevant articles that were published until September 2, 2022. The primary outcome was prolonged postoperative opioid use, and secondary outcomes included the length of stay (LOS), reoperation, the time to return to work (RTW), postoperative complications, gastrointestinal complications, new permanent disability, central nervous system events and infection. In addition, subgroup analysis of the primary outcome was conducted to explore the main sources of heterogeneity, and sensitivity analysis of all outcomes was performed to evaluate the stability of the results. A total of 60 cohort studies involving 13,219,228 individuals met the inclusion criteria. Meta-analysis showed that perioperative opioid use was specifically related to prolonged postoperative opioid use (OR 6.91, 95% CI 6.09 to 7.84, p<.01). Furthermore, the results also showed that perioperative opioid use was significantly associated with prolonged LOS (OR 1.74, 95% CI 1.39 to 2.18, p<.01), postoperative complications (OR 1.72, 95% CI 1.26 to 2.36, p<.01), reoperation (OR 2.38, 95% CI 1.85 to 3.07, p<.01), the time to RTW (OR 0.45, 95% CI 0.39 to 0.52, p<.01), gastrointestinal complications (OR 1.39, 95% CI 1.30 to 1.48, p<.01), central nervous system events (OR 1.99, 95% CI 1.21 to 3.27, p=.07) and infection (OR 1.22, 95% CI 1.09 to 1.36, p=.01). These results were corroborated by the trim-and-fill procedure and leave-one-out sensitivity analyses. Based on the current evidence, patients with perioperative opioid use, in comparison to controls, appear to have prolonged postoperative opioid use, which may increase the risk of poor outcomes including prolonged LOS, complications, reoperation, RTW and so on. However, these results must be carefully interpreted as the number of studies included was small and the studies were statistically heterogeneous. These findings may help clinicians to realize the harmfulness of perioperative use of opioids, reduce the use of prescription opioids, necessarily withdraw before operation or significantly wean to the lowest tolerable preoperative amount, and provide some inspiration for standardizing the use of opioids in the future. [ABSTRACT FROM AUTHOR]

Tantalum nitride (Ta3N5) is one of the most promising photoresponsive semiconductor materials for efficient solar energy conversion, but its fast carrier recombination has hindered research progress severely. Fabricating a heterojunction structure is an effective strategy to promote the charge separation efficiency and thus enhance solar conversion efficiency. Herein, we designed a p-n heterojunction photoanode consisting of n-type Ta3N5 nanorod arrays (NRAs) that grew along the a-axis (light electron effective mass) and p-type Cu2O nanoparticles. This NRA heterojunction shortens the hole diffusion distance, transfers electrons along the a-axis effectively, and enlarges the space charge region. The heterojunction improves the charge separation efficiency of Ta3N5 NRAs significantly, and Ta3N5-Cu2O exhibits a photocurrent density of 9.19 mA cm−2 at 1.6 V vs normal hydrogen electrode (VNHE, pH = 0), an onset potential of 0.326 VNHE, and a maximum incident photon to current efficiency of 60% at 380 nm. Our results demonstrated a potential crystal oriented growth strategy of nanostructured heterojunctions for overcoming the short carrier diffusion distance and fast carrier recombination. [ABSTRACT FROM AUTHOR]

An accurate measurement of force and biomechanical energy that people can impart through kicking is useful for kick-related sports training. Existing methods are indirect measurements or focus on force and not on the total energy of the kick. A kick test rig was designed, constructed and instrumented to measure the force and displacement of a vertical target subjected to kicking. The kick energy was calculated from the recorded force and displacement histories. The methodology for measurement of kick force and energy was validated by an open stance front kick test by 52 volunteers. The results showed that 67% of the participants could achieve an average energy above 100 J. An increasing trend of kick energy with increasing body weight of participant was observed. The participant’s gender had a strong influence on the kick energy, while training in martial arts does not appear to be a significant parameter. A probability analysis showed that one in one hundred adults will be able to kick with energies exceeding 215 J. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the dynamic response of multi-ply woven fabrics subjected to impact by a spherical steel projectile in a velocity regime ranging from 120 to 200 m/s. A plain weave fabric made of Spectra 1000 fibres was used to fabricate test samples having different numbers of layers and fold patterns. The effect of fabric folding was investigated by comparing the impact performance of samples consisting of separate unfolded fabrics, continuous accordion-fold fabrics, and continuous roll-fold fabrics, respectively. It was found that the perforation resistance and energy absorption capacity were significantly improved by folding a fabric into multiple plies compared to the unfolded counterparts, and the roll-fold fabrics performed best in this study. Fabric folding seemed to have only a negligible effect on the back-face deflections of woven fabrics. The effect of thickness (or the number of layers) on energy absorption efficiency was different among the tested fabrics, due to the different inter-layer interactions depending on fold patterns. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study on the impact behaviour of composite laminates made of a Dyneema ® woven fabric and four different resin matrices. Three thicknesses of each kind of resin laminate were subjected to impact by a spherical steel projectile in a velocity regime ranging from 100 to 200 m/s. The results revealed that the laminates having flexible matrices performed much better in perforation resistance and energy absorption, but had a greater extent of deformation and damage than the counterparts with rigid matrices. It was found that the matrix rigidity played a crucial role in controlling the propagation of transverse deformation, and thereby the local strain and perforation resistance of laminates. The more rigid matrix restrained the laminate's transverse deformation to a smaller area at a given time, which led to higher local strain and lower perforation resistance. Fibre failure in tension was identified as the dominant failure mechanism for the tested laminates. [ABSTRACT FROM AUTHOR]

Neuropilin-1 (NRP-1) participates in the progression of cholangiocarcinoma (CCA) and lenvatinib is an approved tyrosine kinase inhibitor treating several other cancers. Our exploratory study reveals that the inhibitory activities of lenvatinib largely rely on the expression levels of NRP-1 in CCA cells, leading to the present study that aims to investigate whether inhibition of NRP-1 could enhance the effects of lenvatinib in suppressing CCA. By using stable transfected CCA cells depleted of NRP-1 and EG00229, a specific NRP-1 inhibitor, we examined cell proliferation, cell cycle distribution and apoptosis, and detected the expression of key molecules and the involvement of the c-Met pathway. Xenograft mouse models were employed to verify the in vitro results. NRP-1 depletion and EG00229 strengthened lenvatinib in inhibiting the proliferation and promoting the apoptosis of CCA cells, and their additive or synergistic effects were confirmed in animal models. Mechanistically, lenvatinib induced the activation of the c-Met pathway, while either NRP-1 depletion or EG00229 inhibited this activation, which could be stimulated by its ligand hepatocyte growth factor. NRP-1 inhibition resulted in a significant alteration in the expression/activation of downstream pathways and molecules, which are key factors regulating cell proliferation and apoptosis. In conclusion, the present results indicate that the inhibition of NRP-1 enhances the efficacy of lenvatinib via the c-Met pathway, and warrant further studies on the pharmacological utility of EG00229, particularly, in the combination of lenvatinib as a promising adjunct therapeutic strategy for combating CCA. • The activities of lenvatinib against CCA cells depend on NRP-1 expression levels. • NRP-1 depletion increases the effects of lenvatinib in inhibiting CCA cells. • EG00229 works with lenvatinib synergistically or additively to suppress CCA cells. • NRP-1 inhibition enhances the efficacy of lenvatinib via the c-Met pathway. [ABSTRACT FROM AUTHOR]

The impact response of sandwich panels is not only dependent on the facesheet but also on the core material. This paper compares the dynamic response of sandwich panels with different core materials when subjected to medium velocity impacts. The sandwich panels were made of aluminium facesheets with five different cores, viz., low density balsa wood, high density balsa wood, cork, polypropylene honeycomb, and polystyrene foam. All the specimens were impacted by an instrumented projectile with a hemispherical steel head at three impact energies of 43, 85 and 120 J. An accelerometer attached to the projectile and a high speed camera were used to collect data and record the impact process. 3D scanning technique was used to measure the deformation of front and back faces after impact. The impact properties of the sandwich panels with the five different cores were compared in terms of contact force, energy absorption, depth of indentation, overall bending deflection, etc. Post-mortem sectioning was conducted to examine the impact induced failures such as facesheet rupture, crush of core material, and debonding between facesheet and core. Finite element modelling was also carried out to elucidate the observed experimental results and further understand the effect of core material. [ABSTRACT FROM AUTHOR]

Haliotis discus hannai Ino ( Haliotis ) is a highly valued marine shellfish, and it is sometimes replaced by another cheaper Gastropoda mollusk, Volutharpa ampullacea perryi ( Volutharpa ). Polysaccharides from pleopods, viscera and gonads of these two gastropods were compared by analyzing the mono- and di-saccharides in their acid hydrolysates using high performance liquid chromatography-mass spectrometry (HPLC-MS n ) after 1-phenyl-3-methyl-5-pyrazolone (PMP) derivatization. Disaccharide analysis revealed the distribution of uronic acid-containing polysaccharides (UACPs) in the biological samples. GlcA-(1→2)-Man, GlcA-(1→3)-GalN, and another disaccharide consisting of a hexuronic acid linked to a hexose were found in the hydrolysates, which indicated the existence of AGSP (abalone gonad sulfated polysaccharide) with the backbone composed of →2)-α-Man(1→4)-β-GlcA(1→ repeating unit, AAP (abalone glycosaminoglycan-like polysaccharide) with the backbone of →3)-GalNAc-(1→2)-GlcA-(1→3)-GalNAc-(1→4)-GlcA-(1→ repeating unit, and unidentified DS1P containing a hexuronic acid linked to a hexose unit, respectively. As shown by extracted ion chromatograms (XICs), AAP was the only UACP found in pleopods of the two gastropods; gonads and viscera of Haliotis contained DS1P and AGSP, while those of Volutharpa contained DS1P, AGSP as well as AAP. Monosaccharides in the acid hydrolysates were demonstrated in XICs by extracting their corresponding PMP derivative quasi-molecular ions one by one, and the results indicated the similar conclusion to the disaccharide analysis. Therefore, it could be concluded that polysaccharides from pleopods of the two gastropods are very similar, while those from their viscera and gonads differ greatly. [ABSTRACT FROM AUTHOR]

• Recent studies on bio-inspired concrete materials and structures are reviewed. • The biological methods of concrete self-healing and soil improvement are discussed. • Bio-inspired building envelopes and facades and their applications are reviewed. • Potential of 3D printing techniques in producing bio-inspired concretes is analysed. • The future prospects of bio-inspired building materials and structures are suggested. Nature provides examples of resilient materials and structures with optimised morphologies and topologies to achieve excellent mechanical and structural properties and sustainable options for the construction industry. This paper provides an overview of nature-inspired materials applicable to buildings and civil structures. Current research on bio-inspired novel cementitious composites, bacteria-enhanced materials, building envelopes and facade systems, advanced manufacturing processes, and their applications are discussed. Moreover, this paper provides insights for future research on designing and developing bio-inspired building materials and resilient structures. [ABSTRACT FROM AUTHOR]

• Steel wire mesh can provide reliable protection against windborne debris. • The impact response of steel wire mesh is dominated by transient transverse waves. • The maximum energy absorption by wire mesh occurs at the ballistic limit velocity. • Wire mesh absorbs energy mainly via the plastic deformation and breakage of wires. Considerable property damage is caused by windborne debris during extreme weather. The object of interest in this study, steel wire mesh, is an effective means of providing protection against windborne debris. However, the design and manufacture of security screens made of wire mesh typically depend on a laborious and imprecise trial-and-error process. Additionally, this anisotropic, inhomogeneous, and porous material comprising in-contact wires has rarely been examined in a comprehensive manner. Considering these issues, the current research experimentally tested the impact response of plain-weave steel wire mesh by firing a spherical projectile in a velocity regime ranging from 112 m/s to 152 m/s. The deformation and failure mechanisms of the wire mesh during the impact process were investigated via high-speed photography. The results showed that the wire mesh behaved as a membrane and failed mainly in tension over the impact velocity range of interest. Further, with a detailed finite element model consisting of interlaced warp and weft wires, additional virtual tests were carried out at a broader velocity range of 20–200 m/s. The findings indicated a linear relationship between residual velocity and impact velocity under a velocity range that exceeded the ballistic limit. The energy absorbed by the wire mesh increased with impact velocity (or impact energy) before the material reached peak absorption at the ballistic limit. Beyond this threshold, the energy absorption gradually declined to an asymptotic level. Such energy absorption was well correlated with the extent of transverse deformation in the wire mesh. Internal energy due to the deformation of wires and frictional energy associated with the interactions between sliding wires at their crossovers were two primary energy absorbing mechanisms. Moreover, the effects of impact location, clamped wire direction and projectile size were analyzed. [Display omitted] [ABSTRACT FROM AUTHOR]

The influence of peak compressive stress on the dyamic tensile fracture (spall) in a multi-phase steel, austenite, ferrite and martensite phases, was investigated in as-received and pre-strained conditions. Plate impact experiments were done at ⁓3.0 GPa and ⁓6.0 GPa compressive peak stresses. Results showed that peak stress increase results in about 20% increase in the spall strength for samples tested in the as-received condition, and about 15% increase for the pre-strained samples. These increases could be related to the effects of peak stress on the tensile stress that causes spallation. However, introducing plastic deformations in the pre-strained samples had negligible effects on the spall strength. Microstructural examinations revealed that incipient spall damage was parallel to the phase boundaries and mainly accommodated by ferrite grains as quasi-cleavage transgranular fracture. Samples shocked in the as-received condition with full spallation experienced a quasi-cleavage fracture within the ferrite compared with a cleavage fracture within the ferrite for samples shocked in the pre-strained condition. Deformation within the austenite phase due to plate-impact testing was dependent on the initial sample condition, the pre-strained samples showed more deformation than the as-received samples. [ABSTRACT FROM AUTHOR]

This study explored the impact response of two bio-inspired composite laminates with linear and non-linear helicoidal fibre architectures. The helicoidal laminates, together with quasi-isotropic and cross-ply control samples, were fabricated using heterocyclic aramid fibres and tested against a spherical projectile under high impact velocities. The results revealed that helicoidal lay-ups with small rotation angles led to inferior perforation resistance and energy absorption capacity when compared to the quasi-isotropic and cross-ply counterparts. The cross-ply configuration was confirmed as the optimal fibre architecture for impact perforation. Post-impact inspections highlighted that the failure mechanisms of laminates were significantly affected by their lay-ups. The number of fractured fibres was found to reduce with the decrease of inter-ply angle. This was due to the small rotation angles promoted a wedge-in mechanism. Moreover, a smaller angle mismatch resulted in diminished overall delamination area in a laminate. Due to these two effects, therefore, helicoidal lay-up configurations with small inter-ply angles are not recommended for impact-resistant laminates reinforced by tough fibres. • High-velocity impact behaviour of bio-inspired helicoidal laminates is explored. • Helicoidal lay-ups perform worse than quasi-isotropic and cross-ply counterparts. • The decrease of inter-ply angle results in fewer fractured fibres. • The overall delamination area reduces as the inter-ply angle decreases. • Tough fibre helicoidal lay-ups are not ideal for resisting high-velocity impact. [ABSTRACT FROM AUTHOR]

Abstract: Hematopoietic stem cells (HSCs) are characterized with long-term self-renewal and multi-lineage differentiation. HSCs preferentially reside in osteoblastic niche that is hierarchically organized so as to exactly regulate HSCs properties and maintain organism hematopoietic homeostasis. Hematopoietic stem cell–mesenchymal stem cell pairings share stem cell niches in adult bone marrow under immune–humoral–neural regulation. Here, we review the hierarchical HSC osteoblastic niche in terms of its localization, composition, function, and multi-layer regulation systems. [Copyright &y& Elsevier]

• UHMWPE yarns are highly sensitive to strain rate at low rates of deformation. • There is a threshold for strain rate above which strain rate effect is negligible. • Plain weave fabrics have better impact performance than satin weave fabrics. • Spherical projectile penetrates UHMWPE fabrics by a 'wedge-through' mechanism. • A mesoscopic modelling approach of woven fabrics at the yarn level is proposed. A comprehensive study on the impact behaviour of UHMWPE woven fabrics is presented in this paper, which consists of four parts: geometric measurement of fabric parameters, tensile testing of constituent yarns, impact testing of fabrics, and numerical modelling of fabrics subjected to impact loading. Two fabric materials, i.e. a plain weave fabric made of SpectraⓇ 1000 fibres and a 4-harness satin weave fabric made of DyneemaⓇ SK75 fibres, were examined. Firstly, the geometric features of fabrics, such as yarn cross-sections and weave profiles, were characterised via microscopic analysis. Then the tensile properties of single yarns at different strain rates were measured, and results showed that UHMWPE yarns are highly sensitive to strain rate at very low loading rates. Tensile strength as well as longitudinal modulus showed a noticeable increase, whereas failure strain and toughness decreased with the increase of strain rate. However, these properties remained nearly constant in the strain rate range from 0.33 to 400 s−1. Furthermore, projectile impact tests were conducted on single-ply and multi-ply fabric targets under different impact velocities. The energy absorption characteristics, perforation mechanism, and yarn pull-out behaviour were analysed. Finally, finite element models of the fabrics were developed based on the measured geometric parameters and tensile properties of constituent yarns. The models were able to accurately simulate the impact response of the fabrics studied. The insights gained from this investigation will facilitate the effective utilisation of UHMWPE fabrics in armour and other protective applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The article discusses the transition period and the acceleration of the Chinese socialist transformation in the 1950's. China has witnessed active academic debates on assessment, while contrary views emerged in relation to the assessment of the Sixth Plenary of the 11th Party Congress in 1981 on the socialist transformation. There was a controversy between political leaders Mao Zedong and Deng Zihui in 1955 regarding the pace of transformation in agriculture.

A pre-stressing technique for improving the ballistic performance of a circular silicon carbide tile has been tested against ø12-mm spherical steel projectile. The confining pre-stress was achieved through a heat-shrunk steel collar and was evaluated through neutron diffraction for the ceramic-collar system. Subsequent ballistic experiments and simulations of the impact event were used to elucidate the mechanisms and benefits of pre-stress on the ballistic response. CT-scans of various specimens, post-impact, show that the pre-stress affects the trajectory of the Hertzian cone and limits the overall damage. Furthermore, simulations qualitatively agreed with the experimental result, showing a reduction in crack propagation and altered paths of damage. Greater confining stress led to higher negative triaxiality, which act to arrest the tensile hoop stresses and corresponding cracks. • Measured strain in pre-stressed SiC tiles using neutron diffraction. • Pre-stress alters Hertzian cone morphology during ballistic loading. • Cover plate behaviour a metric for ballistic performance. • Computational model informs fracture response. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Aqueous lithium‐ion batteries offer promising advantages such as low cost, enhanced safety, high rate capability, and the ability to deliver considerable capacity at 1.8 V, making them ideal candidates for large‐scale reserve power sources for renewable energy. However, the practical application of aqueous lithium‐ion batteries has been hindered by the poor cycle stability of layered cathode materials, including LiCoO2, in neutral aqueous electrolytes. This review examines the working principles, material limitations, and research progress of aqueous lithium‐ion batteries. The types and characteristics of materials used in the cathode of aqueous lithium‐ion batteries are summarized, with a primary focus on the attenuation mechanisms of LiCoO2 when used as the cathode material in aqueous electrolytes. Furthermore, this review explores the advancements in utilizing LiCoO2 in the cathode of aqueous lithium‐ion batteries, as well as the combination with machine learning. By addressing these critical aspects, this review aims to provide a comprehensive understanding of aqueous lithium‐ion batteries and shed light on future development and application prospects. [ABSTRACT FROM AUTHOR]

Plastics offer many advantages and are widely used in various fields. Nevertheless, most plastics derived from petroleum are slow to degrade due to their stable polymer structure, posing serious threats to organisms and ecosystems. Thus, developing environmentally friendly and biodegradable plastics is imperative. In this study, biodegradable cellulose/multi-walled carbon nanotube (MCNT) hybrid gels and films with improved ultraviolet-shielding properties were successfully prepared using cotton textile waste as a resource. It was proven that MCNTs can be dispersed evenly in cellulose without any chemical or physical pretreatment. It was found that the contents of MCNTs had obvious effects on the structures and properties of hybrid films. Particularly, the averaged transmittance of cellulose/MCNT composite films in the range of 320–400 nm (T320–400) and 290–320 nm (T290–320) can be as low as 19.91% and 16.09%, when the content of MCNTs was 4.0%, much lower than those of pure cellulose films (T320–400: 84.12% and T290–320: 80.03%). Meanwhile, the water contact angles of the cellulose/MCNT films were increased by increasing the content of MCNTs. Most importantly, the mechanical performance of cellulose/MCNT films could be controlled by the additives of glycerol and MCNTs. The tensile strength of the cellulose/MCNT films was able to reach as high as 20.58 MPa, while the elongation at break was about 31.35%. To summarize, transparent cellulose/MCNT composites with enhanced ultraviolet-shielding properties can be manufactured successfully from low-cost cotton textile waste, which is beneficial not only in terms of environmental protection, but also the utilization of natural resources. [ABSTRACT FROM AUTHOR]

Woven wire mesh is a metallic fabric outperforming traditional metal sheets in air circulation, weight saving, impact resistance, etc. In this study, the dynamic mechanical response of steel wire mesh subjected to low-velocity impact loading was investigated using both experimental and numerical methods. An instrumented drop-weight impact facility was used for experimental impact tests, with the effects of clamping wire direction, impact energy, impactor's mass and size being considered. The extents of damage to the wire mesh specimens under different loading conditions were evaluated after impact tests. Three types of contact force vs. displacement curves corresponding to the plastic deformation, wire breakage, and perforation of wire mesh were identified. Weft wires were found to be stronger and stiffer than warp wires because they could resist higher peak forces and experienced smaller maximum displacements under the same impact energies. The experimental results revealed that the peak contact force increased with impact energy until wire breakage occurred, after which the peak force remained almost unchanged. With the increase of impactor mass, wire mesh specimens experienced severer damage due to the inertia effect and strain rate effect. Impactor size had a significant influence on the dynamic response of wire mesh; a great increase in peak contact force was found when using a larger impactor tip. Moreover, a mesoscale finite element model was developed to analyse the propagation of stress and the evolution of dynamic failure in wire mesh during impact. The simulation results showed that more than 80% of the impactor's kinetic energy was absorbed through the deformation and failure of wire mesh, while the frictional energy dissipation accounted for about 10% of impact energy. • Three types of contact force vs. displacement curves of wire mesh were identified. • Weft wires could resist higher force corresponding to wire breakage than warp ones. • Wire mesh material behaved in a membrane stretching mode under low-velocity impact. • Impact-induced stress propagated in an orthotropic manner in wire mesh. • More than 80% of impact energy was absorbed as the internal energy of wire mesh. [ABSTRACT FROM AUTHOR]

Microstructural changes and ferrite phase transformation under shock loading, between 8.5 GPa and 17.5 GPa, in a hot-rolled Lean Duplex Stainless Steel (commercially known as LDX 2101) were investigated in as-received and pre-deformed conditions. The latter condition was considered to distinguish classical deformation twins at high strain rates from those associated to the reversible ferrite phase transformation. Plate impact experiments were used to introduce compressive shock loading at peak stresses below and above the stress threshold of the ferrite phase transformation, 13 GPa. Effects of shock loading were also examined by compressing shocked samples quasi-statically and comparing their response with those tested in the as-received condition. The microstructural examinations revealed that the ferrite in LDX 2101 experienced a reversible phase transformation at a peak stress of ~17 GPa. The fingerprints for this transformation were {112}<111> primary twins and {332}<113> primary and secondary twins. In addition, the yield stress of the sample pre-shocked at ~17 GPa showed a considerable increase (⁓150 MPa) compared to the flow stress in as-received conditions. [ABSTRACT FROM AUTHOR]

• The critical shear rate decreases with the increase in temperature. • The formation of shear bands evolving into cracks on the free surface of the STF is observed at 0 °C. • The response time for effective energy absorption is faster at lower temperatures and under higher impact velocities. • A one-dimensional model is presented to predict the response time for energy absorption. Shear thickening fluid (STF) material is a suspension with a certain amount of nano- or micro-particles dispersed into a liquid medium whose viscosity increases with the rate of shear strain. Due to its exceptional rate-dependent property, STF has been regarded as a promising energy absorption material with potential application in soft body-armour. This study examines the rheological, impact resistance and energy absorption characteristics of an STF with concentrated polymer submicron particles under various temperatures. The rheological testing was conducted using a rotational rheometer with a temperature-control hood at shear rates measured from 0.01 s−1. The studies reveal that the shear thickening behaviour of the STF is temperature-dependent and the critical shear rate for the onset of shear thickening decreases with the reduction of temperature. In particular, shear thickening behaviour of the STF at 0 °C was observed with the formation of shear bands evolving into cracks on the free surface of the STF. Low-velocity impact tests were conducted using a drop-weight tower with a temperature-control chamber. The study shows that the impact resistance of the STF increases with the decrease in temperature. In particular, the impact resistance shows an early response time when the impact resistance slowly picks up, corresponding to mechanisms of jamming-associated "solidification" and propagation of front of the "solidified" region. A simple one-dimensional model is also adopted to comprehend the response time for effective energy absorption of the STF addressing the mechanisms, and the general agreement of the predicted response time with that from the experiments demonstrates the effectiveness of the model. [ABSTRACT FROM AUTHOR]

Failure prediction modeling and optimization of composite structure under impact loading is reported in the paper. A methodology is presented to optimize the composite laminate subjected to impact loading considering fiber arrangement as a design variable and residual velocity as an objective function. The fitness function is evaluated using ABAQUS/Explicit that works on the continuum damage mechanics model. The damage behavior of composites obtained through this model is validated with simulation and experiments. The results show a substantial impact of fiber arrangement on residual velocity, penetration, energy absorption capacity and ballistic limit of the plate. [ABSTRACT FROM AUTHOR]

This article proposes a new model for predicting sunspot activity based on the inverse number and intelligent fixed point. Firstly, in the training phase, the optimal parameters of the model are selected by the inverse-number formula and intelligent fixed-point algorithm. Secondly, in the validation phase, the model is verified by the data. Finally, the model is applied to the prediction of monthly mean sunspot number (MSN). The model's predictions are compared with those of autoregressive models (AR) and the National Oceanic and Atmospheric Administration (NOAA) predictions. The results show that the prediction accuracy of the proposed method is higher than that of previous methods. The method is then used to predict the 13-month smoothed monthly total sunspot number (MSSN13), and a higher prediction accuracy is obtained. The model proposed in this article is theoretically complete and robust. [ABSTRACT FROM AUTHOR]

Abstract The dynamic responses of sandwich panels with homogeneous and stepwise graded aluminium foam cores subjected to impact loadings were investigated via experimentation and finite element simulation in this paper. The low-velocity impact tests were conducted using a drop-weight impact facility at four different velocities, the results of which were compared in terms of force-displacement response, energy absorption and damage status. It was found that the density gradient of graded foam cores had a marked influence on the deformation and failure behaviour of front facesheets. Moreover, different facesheet materials were experimented with a homogeneous foam core, and the results showed that the impact response of a sandwich panel was dominated by its front facesheet. The front facesheets having same materials deformed and failed in the same manner irrespective of the back facesheet materials. The results of finite element analysis indicated that the critical impact energy required to cause failure to the front facesheet increased with the density of first core layer. Besides, the impact performance of sandwich panels could be improved efficiently by increasing the front-to-back thickness ratio while the total thickness of both facesheets remained the same. Graphical abstract Unlabelled Image Highlights • The density gradient of graded foam cores markedly influenced the deformation and failure behaviour of front facesheet. • The critical impact energy required to cause failure to the front facesheet increased with the density of first core layer. • The perforation resistance of entire sandwich panels was affected slightly by the core density gradient. • The impact performance of sandwich panels was improved by increasing the thickness ratio of front to back facesheet. [ABSTRACT FROM AUTHOR]

Highlights • Increasing facesheet thickness caused smaller deformation depths but larger deformation areas. • Core height had a small effect on the ballistic limit velocity of sandwich panels. • Front facesheet failed more easily due to stress concentration with the increase of core stiffness. • The increase of front-to-back thickness ratio led to higher damage resistance. • A structural optimisation for maximising the specific energy absorption was presented. Abstract This paper presents a combined experimental and numerical study on the dynamic response and failure mechanisms of honeycomb sandwich panels subjected to high-velocity impact by a spherical steel projectile. Impact tests were performed in a velocity range from about 70 to 170 m/s to investigate the effects of facesheet thickness, core height, cell wall thickness and cell size of honeycomb on the impact behaviour of sandwich panels. These geometric parameters were found to influence the impact performance mainly by changing the deformation and failure mechanisms of both sandwich facesheets. Moreover, the ballistic limit velocity and critical perforation energy of each sandwich configuration were obtained by numerical simulation. It was found that increasing facesheet thickness and reducing honeycomb cell size were two weight-efficient ways to enhance the perforation resistance of sandwich panels when the areal density exceeded a certain value. The projectile's penetration process into the sandwich panel and the associated energy absorbing mechanisms were analysed, the results of which showed that facesheets contributed most to energy absorption. Further numerical simulation was conducted to explore the influences of core stiffness and the thickness ratio of front to back facesheet. It was found that core stiffness had a significant effect on the deformation and failure initiation of front facesheet; more specifically, the front facesheet failed more easily due to stress concentration with the increase of core stiffness. When the total thickness of front and back facesheets remained constant, increasing the front-to-back thickness ratio led to higher damage resistance but greater deformation area on the front facesheet. Finally, a discrete optimisation was conducted to generate an optimal design of sandwich structure for achieving the highest specific energy absorption without perforation under a certain impact energy. The optimised sandwich panel exhibited an increase of 23.7% in specific energy absorption compared with the initial design. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the stiffness and energy absorption capabilities of three proposed biomimetic structures based on the internal architecture of a cornstalk. 3D printing was used to manufacture specimens using a tough and impact-resistant thermoplastic material, acrylonitrile butadiene styrene (ABS). The structural stiffness, maximum stress, densification strain, and energy absorption were extracted from the compression tests performed at a strain rate of 10−3 s−1. A numerical model was developed to analyse the behaviour of the biomimetic structures under compression loading. Further, a damage examination was conducted through optical microscopy and profilometry. The results showed that the cornstalk-inspired biomimetic structure exhibited a superior specific energy absorption (SEA) capability that was three times higher than that of the other core designs as reported in the literature. [ABSTRACT FROM AUTHOR]

Background: Castleman disease (CD) is a rare and heterogeneous lymphoproliferative disorder with a spectrum of characteristic pathological abnormalities of lymph node. Furthermore, its clinical diagnosis is very challenging until pathological results are available. This study aimed to investigate the clinical presentations, treatment and prognosis of CD, thereby improving the understanding and diagnosis of CD.Methods: This study retrospectively analyzed the clinical data of 31 patients with CD admitted to the First Hospital Affiliated Hospital of Chongqing Medical University January 2013 to December 2020. The chi-square test and the Mann-Whitney rank sum test were employed to calculate between-group differences for categorical and quantitative data, respectively.Results: Clinically, patients with unicentric CD (UCD) usually present with lymphadenopathy. However, the clinical presentation of patients with multicentric CD (MCD) ranged from mild lymphadenopathy with B-symptoms (5/8, 62.5%) to intense inflammation, vascular leak syndrome (3/8, 37.5%), hepatosplenomegaly (3/8, 37.5%), organ insufficiency (3/8, 37.5%), and even death (2/8, 25.0%). Compared with UCD patients, patients with MCD had significantly lower levels of hemoglobin (104 (90,129) vs 137 (120,149), p=0.018) and plasma albumin (31.5 (27.0,37.0) vs 45.0 (40.0,46.5), p=0.001), but IgG levels were significantly increased. Patients with UCD were mainly treated with surgical resection alone, with a five-year survival rate of 95.65%. When siltuximab is not an option, steroid plus rituximab-based chemotherapy and specific supportive care are common options for MCD. Except for 2 deaths, the remaining MCD patients have stable disease or partial remission.Conclusion: CD describes a heterogeneous group of disorders characterized by morphologically benign lymphoid hyperplasia. Notably, patients with MCD present varying degrees of inflammation responses, even involving multiple systems. Surgery is a direct and effective way to diagnose and treat UCD. In the absence of IL-6 antagonists, anti-inflammatory and immunosuppressive therapeutic strategies, and cytotoxic clearance of cells responsible for hypercytokinemia could be adopted. [ABSTRACT FROM AUTHOR]

• Outperforms existing techniques by identifying both single and non-overlapping delaminations effectively. • Integrates theory, experiments, and algorithms for precise delamination assessment in composites. • Identifies locations and sizes of non-overlapping delaminations in composites. • Potential for future expansion to detect multiple delaminations, enhancing broader applicability. Extensive research has been carried out on the detection of single delamination in fibre-reinforced polymer (FRP) structures using different structural health monitoring (SHM) approaches, including the vibration-based assessment methods. However, there are limited studies that on the detection of multiple delaminations, which could occur in many real-world scenarios. To address this research gap, this paper aims at developing a vibration-based method to assess the two non-overlapping delaminations in FRP beams based on changes in natural frequencies. A theoretical model of vibrating FRP beams with two non-overlapping delaminations was constructed and used for generating the multiple frequencies of the delaminated beams. By analysing the frequency shifts of the FRP beams before and after the occurrence of damage, the delamination characteristics (location and severity) can be inversely predicted using optimisation algorithms. The accuracy and efficiency of the frequency-based inverse algorithm were verified experimentally by modal testing on FRP beam specimens with one and two non-overlapping delaminations. It is interesting to observe that using the proposed vibration-based method, the single delamination in FRP specimens can also be predicted as two non-overlapping delaminations, with a major one matching the original single delamination and a minor one that can be neglected. Thus, the current vibration-based delamination assessment approach is flexible in identifying the prediction of either single or double non-overlapping delaminations in FRP beams, and therefore, it potentially has wider applicability than the existing single delamination detection methods. [ABSTRACT FROM AUTHOR]

Porous structures fabricated through selective laser melting (SLM) are prospective candidates for high-energy-absorbing applications due to their tuneable mechanical properties. The Menger Fractal Cube (MFC) is a unique fractal cube formed through iterative removal of smaller cubes from a larger one. It is distinguished by its intricate self-similar pattern of voids and cubes repeating at diminishing scales, resulting in a lightweight and highly complex structure. Using AlSi7Mg, compression experiments and simulations investigated MFCs with three different orders. Digital image correlation was used to identify the stress concentration areas within the elastic deformation range of MFCs, and the relationship proposed in the Gibson-Ashby model was successfully implemented. The nature of the collapse, fracture mechanism, and energy absorption behaviour were investigated with the plateau and densification region deformation profiles. The highest level of specific energy absorption was recorded in third-order MFC, whereas the maximum densification displacement and energy absorption efficiency were observed in the fourth-order MFC. The test results also showed that the peak force decreased with increasing fractal order, suggesting that high-order MFCs can be employed as protective sacrificial structures that reduce force transmission to the protected structures. In brief, MFCs demonstrate outstanding energy absorption properties and hold promising potential for a wide range of structural applications that require energy-damping characteristics. • The Menger fractal cube inspired porous structures are proposed as a high performing energy absorbing structure. • The densification point of MFCs is getting higher with the increasing fractal order allowing them to absorb more energy. • The Finite Element models predict the mechanical behaviour of Menger fractal inspired porous structures. • Higher order MFCs have greater SEA values in the range of 45-50 J/g. [ABSTRACT FROM AUTHOR]

• Cover plate improves the auxetic response of target. • The thicker the cover plate, the better the auxetic response. • Different overall behaviour observed with different auxetic material structures. • ABS structure behaved poorly, with brittle failure and delayed auxetic response. This study investigated how mild steel cover plates of various thicknesses affected the collapse of re-entrant auxetic structures under penetration at 500 m/s by ø16 mm spherical projectiles. A combination of experimental and numerical methods was used to capture this effect with auxetic structures made from 3D printed titanium alloy (Ti6Al4V) and ABS plastic (acrylonitrile butadiene styrene), and wire cut 304 stainless steel (SS304). Experimentally, structures were tested with a 2.90 mm cover plate and without the cover plate. Numerically, the effect of the cover plate thickness on the auxetic response of the structure was tested with 0.95 mm, 1.50 mm, and 2.90 mm cover plates (as well as no cover plate). The auxetic densification was found to be greatest under the thickest cover. Material characterisation tests were conducted to develop strength and failure models for the mild steel cover and back plates in this study, which produced simulated correlation to the ballistic experiments. Although the simulated auxetic effect generally increased with cover plate thickness, similar to the experiments, the structure material significantly affected the range of this dependence. For the ductile SS304 structures, a thin (0.95 mm) cover plate showed a small improvement in the auxetic response, with a marked improvement with a 1.50 mm cover plate. Whereas the Ti6Al4V structures showed a steady improvement in auxetic densification as the cover plate thickness was increased. Overall densification of the ABS structures was significantly improved by adding cover plates, however collapse was delayed compared to the other materials. These findings therefore indicate that the thickness of cover plates in auxetic sandwiches can be specifically engineered to maximise auxetic effect while considering the ranges of this dependence with different auxetic materials. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) may impair bone development in adolescence, which impacts life-long bone health. No previous studies have examined prospective associations of individual PFAS and their mixture with bone mineral density (BMD) changes in Hispanic young persons, a population at high risk of osteoporosis in adulthood. To examine associations of individual PFAS and PFAS mixtures with longitudinal changes in BMD in an adolescent Hispanic cohort and examine generalizability of findings in a mixed-ethnicity young adult cohort (58.4% Hispanic). Overweight/obese adolescents from the Study of Latino Adolescents at Risk of Type 2 Diabetes (SOLAR; n = 304; mean follow-up = 1.4 years) and young adults from the Southern California Children's Health Study (CHS; n = 137; mean follow-up = 4.1 years) were included in this study. Plasma PFAS were measured at baseline and dual x-ray absorptiometry scans were performed at baseline and follow-up to measure BMD. We estimated longitudinal associations between BMD and five PFAS via separate covariate-adjusted linear mixed effects models, and between BMD and the PFAS mixture via quantile g-computation. In SOLAR adolescents, baseline plasma perfluorooctanesulfonic acid (PFOS) was associated with longitudinal changes in BMD. Each doubling of PFOS was associated with an average −0.003 g/cm2 difference in change in trunk BMD per year over follow-up (95% CI: −0.005, −0.0002). Associations with PFOS persisted in CHS young adults, where each doubling of plasma PFOS was associated with an average −0.032 g/cm2 difference in total BMD at baseline (95% CI -0.062, −0.003), though longitudinal associations were non-significant. We did not find associations of other PFAS with BMD; associations of the PFAS mixture with BMD outcomes were primarily negative though non-significant. PFOS exposure was associated with lower BMD in adolescence and young adulthood, important periods for bone development, which may have implications on future bone health and risk of osteoporosis in adulthood. • PFOS was associated with decreased rates of BMD change in Hispanic adolescents. • In mixed-ethnicity young adults, PFOS was additionally associated with lower BMD. • PFAS mixture effects on BMD were primarily negative though non-significant. • Findings support existing evidence and include a largely Hispanic study population. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are pollutants linked to adverse health effects. Diet is an important source of PFAS exposure, yet it is unknown how diet impacts longitudinal PFAS levels. To determine if dietary intake and food sources were associated with changes in blood PFAS concentrations among Hispanic young adults at risk of metabolic diseases. Predominantly Hispanic young adults from the Children's Health Study who underwent two visits (CHS; n = 123) and young adults from NHANES 2013–2018 who underwent one visit (n = 604) were included. Dietary data at baseline was collected using two 24-hour dietary recalls to measure individual foods and where foods were prepared/consumed (home/restaurant/fast-food). PFAS were measured in blood at both visits in CHS and cross-sectionally in NHANES. In CHS, multiple linear regression assessed associations of baseline diet with longitudinal PFAS; in NHANES, linear regression was used. In CHS, all PFAS except PFDA decreased across visits (all p < 0.05). In CHS, A 1-serving higher tea intake was associated with 24.8 %, 16.17 %, and 12.6 % higher PFHxS, PFHpS, and PFNA at follow-up, respectively (all p < 0.05). A 1-serving higher pork intake was associated with 13.4 % higher PFOA at follow-up (p < 0.05). Associations were similar in NHANES, including unsweetened tea, hot dogs, and processed meats. For food sources, in CHS each 200-gram increase in home-prepared food was associated with 0.90 % and 1.6 % lower PFOS at baseline and follow-up, respectively, and in NHANES was associated with 0.9 % lower PFDA (all p < 0.05). Results suggest that beverage consumption habits and food preparation are associated with differences in PFAS levels in young adults. This highlights the importance of diet in determining PFAS exposure and the necessity of public monitoring of foods and beverages for PFAS contamination. [ABSTRACT FROM AUTHOR]

Environmental pollution and energy shortages are global issues that significantly impact human progress. Multiple methods have been proposed for treating industrial and dyes containing wastewater. Ultrasonic degradation has emerged as a promising and innovative technology for organic pollutant degradation. This study provides a comprehensive overview of the factors affecting ultrasonic degradation and thoroughly examines the technique of acoustic cavitation. Furthermore, this study summarizes the fundamental theories and mechanisms underlying cavitation, emphasizing its efficacy in the remediation of various water pollutants. Furthermore, potential synergies between ultrasonic cavitation and other commonly used technologies are also explored. Potential challenges are identified and future directions for the development of ultrasonic degradation and ultrasonic cavitation technologies are outlined. [Display omitted] • Ultrasonic degradation: a solution for environmental pollution and energy issues. • Exploring acoustic cavitation's ability to efficiently degrade water pollutants. • Examining ultrasonic cavitation's synergy with advanced wastewater treatment technologies. • Addressing the gap between academic and industrial use of ultrasonic cavitation. • Outlining a strategy for ecological conservation through optimizing ultrasonic technology. [ABSTRACT FROM AUTHOR]

In this study, we describe the development of a shell model-based macro-scale approach for a stainless steel 304 wire mesh using Hill's yield criterion and elasto-plastic material behaviors. The constants for orthotropic elastic-material response and the parameters for non-linear behavior were determined from experimental tests. For validation and comparison, the results obtained using this macro-scale model were compared with the experimental data obtained from drop-tower impact tests and the simulation results from a meso-scale model. The comparison highlighted that the macro-scale model of the wire mesh is more suitable for large-size simulations. [ABSTRACT FROM AUTHOR]

This paper presents a combined experimental and numerical study on the low-velocity impact behavior of honeycomb-core sandwich panels with different structural parameters, including facesheet thickness, core height, honeycomb cell size, and cell wall thickness. Impact tests were conducted at four different energies using a drop-weight impact facility, and the deformation and damage characteristics of the tested sandwich panels were analyzed by microscopic X-ray computed tomography. The experimental results revealed two distinct failure modes of sandwich panels: namely mode A, with localized damage in both facesheets and core, which is dominated by indentation; and mode B, which is characterized by global bending deflection of the facesheets and overall core crushing. It was found that a sandwich panel with thin facesheets and a high-density honeycomb core (e.g. with a small cell size and/or a thick cell wall) tended to fail in mode A, but core height did not influence the failure mechanism notably. Furthermore, finite element modeling was carried out to gain further understanding of the effects of these structural parameters. The perforation resistance and energy absorption capacity were significantly enhanced with increasing facesheet thickness. Whereas reducing the cell size and/or thickening the cell wall resulted in lower perforation resistance. When the total thickness of facesheets remained a constant, the impact behavior of the sandwich structure could be optimized by controlling the thickness ratio of the front to back facesheets. Finally, cost efficiency analysis was performed to achieve a rational design of the sandwich structure considering both the impact performance and cost. • Two failure modes of sandwich panels are discovered under low-velocity impact. • Failure mode depends on facesheet thickness, cell size, and cell wall thickness. • Core height does not influence the failure mechanism notably. • The density of honeycomb core shows a negative effect on perforation resistance. • A cost efficiency analysis is proposed to balance the impact performance and cost. [ABSTRACT FROM AUTHOR]

The present paper addresses the development of bio-inspired composite laminates based on the Fibonacci sequence for impact resistant applications. Four methods such as thickness ratio (FT), incremental angle (FI), hybrid (FY) and Fibonacci helicoidal (FH) are devised to create various sets of laminates to exploit the Fibonacci sequence into the laminate design. These methods include controlling of ply group thickness (FT), rotation fiber angle (FI), both thickness and angle (FY), and direct implementation of Fibonacci based helicoidal laminate sequence (FH). The performance of these proposed laminates is analysed by considering ballistic impact loading with six different impact velocities, out of which three are below the ballistic limit of laminates. The behaviour of these laminates under this loading is investigated using an elastic-plastic progressive damage based numerical model. The results obtained through numerical simulation are validated with experimental results and found to be well correlated. The performance of bio-inspired laminates is compared with conventional cross-ply and quasi-isotropic laminates in terms of various parameters such as residual velocity, displacement, energy absorption, peak load, number of plies damaged and delamination. These parameters are correlated by using a level-based methodology and the most versatile method to design Fibonacci based bio-inspired laminates among all methods considered is estimated for all velocities. [ABSTRACT FROM AUTHOR]

This work studied the mechanical response and the associated microstructures and failure mechanisms of additively manufactured Ti matrix composites with in-situ synthesised Ti 2 Ni and TiC x reinforcements under a variety of loading rates. The composites were fabricated using directed energy deposition technique with Ti–6Al–4V (Ti64) and Ni coated graphite (NCG) powders. Different proportions of Ti64 and NCG were mixed to manufacture the specimens with different compositions. Compression tests were conducted at strain rates in the range of 10−3 to 800 s−1. Our results show that the metallurgical and mechanical properties of the composites change with the NCG fraction. The failure mechanisms of the composites are a combination of tensile fracture of brittle TiC x precipitates and shear of the Ti matrix. The composites with higher NCG content exhibit increased strength, reduced ductility and less strain rate sensitivity. Under high strain rate compression loading, the Ti–Ni–C composite can provide enhanced strength with the ductility unchanged, which make it a prospective material for the applications subjected to impact loads. [ABSTRACT FROM AUTHOR]

Improving the charge separation and transport efficiency at semiconductor‐electrolyte interface is critical for high‐performance photoelectrochemical (PEC) water‐splitting devices. Here, the core‐shell‐structured Ni@Co nanoislands were electrodeposited onto the surface of n‐type Si photoanode to construct a metal‐insulator‐semiconductor (MIS) structure. We discover that the high‐quality interface in Si/SiOx/Ni MIS structure is more efficient for charge extraction and transfer than Si/SiOx/Co. Owing to a slightly higher work function for Co (5.0 eV) than Ni (4.6 eV), the Si/SiOx/Ni@Co exhibits the larger band bending to enhance the charge separation efficiency, while the in‐situ formed CoOOH significantly increases the charge injection efficiency due to the decreased oxygen‐evolution overpotentials. As a result, the Ni@Co core‐shell nanoparticles coupling with n‐Si photoanode can afford the PEC performance with an onset potential of 1.02 V versus reversible hydrogen electrode (RHE), saturated current density of 36.7 mA cm−2, and retain good stability in K‐borate buffer solution. This core‐shell structure strategy is efficient and easy to achieve the separation of photogenerated carriers and improve the charge injection efficiency to nearly 100 % She sells core shells: Core‐shell Ni@Co nanoparticles were synthesized on n‐type Si substrate with an island distribution. In this photoanode, Ni has good contact with Si and forms a MIS structure as high‐function metal core, enabling effective photogenerated carriers separation. And the amorphous Co shell with higher work‐function than Ni core could remarkably improve the charge injection efficiency. Therefore, this device achieves high activity in water oxidation to 10.65 mA cm−2 at 1.23 VRHE and 36.7 mA cm−2 at 1.8 VRHE. [ABSTRACT FROM AUTHOR]

The existing damage constitutive models for a composite lamina under impact loading have mainly considered four failure modes: longitudinal fiber failure in tension and compression, matrix failure in tension and compression along the transverse direction. However, when subjected to an impact load in the out-of-plane direction, through-thickness compression failure may also occur in laminates. Therefore, the present paper has established a damage constitutive model considering through-thickness compression failure and has compared it to those constitutive models without such consideration to see the improvement in the impact response analysis and to discuss the necessity of including through-thickness compression damage in the simulation. To this end, impact testing was conducted on manufactured composite panels, and the results were used to validate the finite element simulation of composite laminates under impact. The results showed that the constitutive model with the compression failure mode in the thickness direction had higher accuracy in predicting the impact force, displacement, damage, and energy absorption of laminates. The predicted results by the developed constitutive model showed that through-thickness compression damage indeed occurred in the laminates during the impact process, and it was mainly concentrated in the layers near the impact side. In the layers near the rear side, the tension damage of longitudinal fiber and matrix mainly initiated and developed in the annular region around the impact center on the laminates. [ABSTRACT FROM AUTHOR]

Functionally gradient materials (FGMs) primarily composed of a discretely layered structure with relatively sharp macroscopic interfaces are highly susceptible to interlayer failure under impact loading. Nacre is regarded as a model system for lightweight armor with high impact-resistant performance owing to its multiple length-scale and gradient structures. However, the simultaneous translation of both structural features into artificial assemblies remains challenging. Herein, we constructed new B 4 C/2024Al FGMs with eliminated sharp interfaces, which reproduced the hierarchical and gradient architectures of nacre. A combined experimental and numerical approach was employed to investigate the protective mechanisms of nacre-like FGMs subjected to 7.62 mm armor-piercing incendiary bullet, and two homogeneous composites were also tested under the same conditions for comparison purposes. The FGMs exhibited improved performance to resist ballistic attacks and maintain integrity compared with the uniform structures. As the ceramic contents decreased along the thickness, the energy dissipation mechanisms transitioned from eroding projectile to plastic deformation. The toughness gradient and varying energy dissipation modes prevented the formation of crushed cones at the ceramic-rich layers. The nacre-like structure created several extrinsic toughening mechanisms, which led to the increased energy-absorbing capability of the target. Meanwhile, the eliminated abrupt interfaces avoided the occurrence of interlayer tearing by diminishing the tensile wave strength and the sudden change of wave impedance, which prolonged the projectile-target interaction period and strengthened the eroding effect on the projectile. The present study opens new opportunities to design advanced lightweight FGMs armors with high impact-resistant protective performance. [ABSTRACT FROM AUTHOR]