Controlled Preparation of Highly Stretchable, Crack-Free Wrinkled Surfaces with Tunable Wetting and Optical Properties.

Constructing wrinkles by utilizing strain-driven surface instability in film-substrate systems is a general method to prepare micronano structures, which have a wide range of applications in smart surfaces and devices such as flexible electronics, reversible wetting, friction, and optics. However, cracks generated during the preparation and use process significantly affect the uniformity of wrinkled surfaces and degrade the functional properties of the film devices. The realization of crack-free wrinkles with high stretchability in hard film systems is still a great challenge. Here, we report on a facile technique for controllable preparation of large-area, highly stretchable, crack-free wrinkled surfaces by ultraviolet ozone (UVO) treatment of Ecoflex. The thickness dependence of the wrinkles and the in situ wrinkling process during mechanical loading are investigated. The wrinkles including striped, labyrinth-like, herringbone, and transitional structures are controllable by changing strain mode (uniaxial or biaxial), loading history (simultaneous or sequential), strain anisotropy, and gradient loading. The wrinkled surfaces obtained using UVO-treated Ecoflex have tunable wetting and optical properties and can maintain excellent mechanical stability under large strains. This study provides a facile method for the preparation of large-area, crack-free wrinkles, which is simple, fast, low-cost, and robust. The resulting wrinkled surfaces remain stable under high stretching, which is beneficial for many practical applications, especially in the cases of large strains.

Melatonin Attenuates Cisplatin-Induced Ototoxicity via Regulating the Cell Apoptosis of the Inner Ear.

Objective: The mechanism of ototoxicity caused by cisplatin is currently unclear, and the induced apoptosis may play an important role in inner ear injury. Melatonin has high antioxidant and antiapoptotic effects. This study is aimed at clarifying the protective effect on the inner ear and the underlying mechanism of melatonin. Design: The mice and HEI-OC1 cells were randomly separated into four groups: control group, cisplatin group, melatonin group, and cisplatin exposure after melatonin pretreatment group. Place and Duration of the Study. From September 2018 to September 2021, all experiments were completed at the Second Hospital of Shandong University. And the study was approved by the Ethics Committee of the Second Hospital of Shandong University (KYLL-2020 (KJ) A-0191). Methodology. Mice were pretreated with peritoneal injection of melatonin prior to the application of cisplatin. Auditory Brainstem Response (ABR) test was performed before and after treatment, then the temporal bones were collected for histology investigation. HEI-OC1 cells were pretreated with melatonin before adding cisplatin. The apoptosis of HEI-OC1 cells was observed by MTS, TUNEL, and flow cytometry, respectively. Moreover, the mRNA expression of apoptosis-related factors was detected by qRT-PCR. Results: ABR and morphological analysis showed that cisplatin caused damage to the function and structure of the inner ear. MTS, TUNEL, and flow cytometry showed that the application of cisplatin caused a significant increase in the apoptosis level of HEI-OC1 cells, and melatonin pretreatment reduced this damage. Moreover, melatonin pretreatment reversed the mRNA expression changes of apoptosis-related factors induced by cisplatin. Conclusions: Apoptosis is involved in the inner ear dysfunction caused by cisplatin. Melatonin reduces the ototoxicity of cisplatin by regulating the induced apoptosis response.

Preparation of Magnetic Metal-Organic Frameworks@Molecularly Imprinted Nanoparticles for Specific Extraction and Enrichment of Bisphenol A in Food.

Metal-organic frameworks (MOFs) with systematically tailored structures have been suggested as promising precursors to the preparation of diverse functional materials. Herein, a facile and versatile layer-by-layer strategy without any special surface modifications has been proposed for the preparation of magnetic metal-organic frameworks (MMOFs) supported molecularly imprinted polymer nanoparticles (MMOFs@MIP), which are based on a magnetically susceptible core conjugated with an imidazole-derived self-assembled layer and a silane-based imprinted shell. The obtained MMOFs@MIPs, which integrated the advantages of Fe3O4, MOFs, and MIPs, were characterized and exhibited good magnetic properties, a rapid mass transfer rate, and an excellent adsorption selectivity as well as capacity for the targeted molecular - bisphenol A (BPA). Moreover, the MMOFs@MIPs were employed as adsorbents in magnetic solid phase extraction (MSPE) to selectively bind and rapidly separate BPA from real samples with satisfactory recoveries ranging from 88.3% to 92.3%. More importantly, the desirable reusability of MMOFs@MIP was also evaluated, and the recoveries still maintained above 88.0% even after five re-use cycles. Furthermore, combined with high-performance liquid chromatography (HPLC) analysis, a novel MSPE-HPLC method was developed, enabling the highly selective and sensitive detection of BPA in a wide linear range of 0.5-5000 µg L-1 with a low limit of detection (LOD) of 0.1 µg L-1. This work contributes a promising method for constructing various functional nanoparticles @MOFs@MIP hybrid materials for applications in many different fields.

Hydrodynamics of Irregular-Shaped Graphite Particles in Coaxial Two-Phase Jet Flow.

Expanded graphite particle is characterized by the low density in comparison with those of bead glass and copper particles. Hydrodynamics of the irregular-shaped graphite particle swirling flows in a coaxial chamber are investigated via an improved kinetic frictional stress model. A drag force coefficient considering the effects of irregular shapes based on the artificial neural network algorithm is adopted to describe the momentum transfer between nonspherical particles and gas phases. The proposed model, algorithm, and source code for modeling and simulation are validated by measurement using spherical glass beads, and acceptable agreement is obtained. Lower sphericity particles enhance the anisotropic particle dispersions and induces the redistributions of the Reynolds stresses of the two-phase flow. Irregular-shaped particles are more sensitive to the gas followability instead of own inertia, whereas spherical particles are easier to be affected by the inlet effects. The interlock force between nonspherical particles takes great effect on particle flow than the spherical particle. The axial-axial normal stresses of sphericities of 0.63 and 0.72 are approximately 3.4 times larger than those of shear stress of spherical particle, and their axial velocities locating at near central regions are 3.0 times larger than those of sphericities.

Transient behavior of compressed magnetorheological brake excited by step currents.

Transient behavior of a magnetorheological brake excited by step currents under compression-shear mode has been experimentally studied. The results show that the amplitude of the applied current had little effect on the rising time of transient torque, while the rising time was significantly affected by the rotational speed, the compressive speed and the compressive strain position. The falling time of transient torque was independent of the amplitude of the applied current, the compressive speed and the compressive strain position, and it was affected by the rotational speed. The falling time of the transient torque was much shorter than the rising time by a step current. The transient process of MR brake applied as a step current was different from a stable process pre-applied at constant current in different particle chain structure forming processes. In addition, the compressive processes applied in one step current and randomly on/off current were compared and experimentally verified: the particle chains in two processes both experienced the same evolutionary of transient torque. The results achieved in this study should be properly considered in the design and control of magnetorheological brake under compression-shear mode.

Hydrodynamic Modeling of Turbulence Modulation by Particles in a Swirling Gas-Particle Two-Phase Flow.

Turbulence modulations by particles of a swirling gas-particle two-phase flow in an axisymmetric chamber are numerically simulated. To fully consider the preferential concentrations and the anisotropic dispersions of particles, a second-order moment model coupling particle-particle collision model was improved. Experimental validation for the proposed model, algorithm, and in-house codes by acceptable match was carried out. The effects of ultralight-expanded graphite and heavy copper particles with a large span of Stokes number on gas velocities and fluctuations, Reynolds shear stresses and tensor invariants, turbulence kinetic energies, and vortice structures are investigated. The results show that turbulent modulation exhibits strong anisotropic characteristics and remains in a close relationship with the flow structure. Modulation disturbances and vortex evolution are enforced by heavy-large particles with higher Stokes numbers. Preferential accumulations of ultralight particles in shear stress regions at lower vortices are weaker than those of heavy particles. For axial turbulence modulations, a heavy particle plays the primary role in the inhibition action because of larger inertia, and a light particle contributes to the enhancement effect due to excellent followability. The instantaneous flow information and coherent turbulent structure are failed to be acquired due to the limitation of the Reynolds time-averaged algorithm.

Compressions of magnetorheological fluids under instantaneous magnetic field and constant area.

Compressions of magnetorheological (MR) fluids have been carried out under instantaneous magnetic fields. The yield strength of the MR fluid in compressive mode has been derived by assuming that it was a transformed shear flow in Bi-visous model. The compressive stresses have experimentally studied under different magnetic fields, different initial gap distances and different compressive velocities. The nominal yield shear stresses of the compressed MR fluid under different influential factors have been calculated. The compressive stress increased in a power law as the applied magnetic field increased, while it decreased as the initial gap distance and the compressive velocity increased. With the increase of magnetic field, the difference between the nominal yield shear stress curves increased, and the exponents of the power law increased with the increase of the magnetic field strengths. A larger initial gap distance and a lower compressive velocity resulted in a higher nominal yield shear stress under the same instantaneous magnetic field. The achieved results of the nominal yield shear stress with magnetic field seemed to deviate from the prediction of dipole model, and the chain structure aggregation effect, the sealing effect and the friction effect by compression should be considered.

Hydrodynamic Modeling of Swirling Binary Mixture Gas-Particle Flows Using a Second-Order-Moment Turbulence Model.

The polydisperse behaviors of a binary ultralight-heavy mixture particle flow in a swirling axisymmetric chamber were investigated based on a developed second-order-moment gas-particle turbulent model. A binary particle Reynolds stress transport equation to depict the anisotropic interactions between gas-mixture particles and binary ultralight-heavy particles was established to close the governing equations. Hydrodynamic parameters, including particle number density, particle and gas velocities, and fluctuation velocities, Reynolds stress tensors, and their invariants, turbulent kinetic energy, and vortex structure, are numerically simulated. The detailed effects of the density, the diameter of the particle, the Stokes number, and the ultralight particle mass loading ratios on the flow status were studied. It is shown that normal and shear Reynolds stresses and kinetic turbulent energies of mixture particles have been redistributed, particularly, they are very sensitive to the mass loading ratios. Higher particle mass loading ratios enhanced the anisotropic characteristics. The particle number density at central regions of the farthest downstream is approximately three times larger than those of smaller mass loading ratios. Larger Stokes number particles reinforced the axial fluctuations up to 1.2 times that of the light particles, whereas ultralight particles increased tangential fluctuation to 2.5 times for axial ones.

A unique radioprotective effect of resolvin E1 reduces irradiation-induced damage to the inner ear by inhibiting the inflammatory response.

BACKGROUND: In addition to the direct effects of irradiation, the induced inflammatory response may play an important role in the damage to the inner ear caused by radiotherapy for the treatment of head and neck cancers. Resolvin E1 (RvE1) has anti-inflammatory activity, acting by reducing neutrophil infiltration and proinflammatory cytokine expression. Therefore, in this study we sought to confirm whether the inflammation induced by irradiation was involved in damage to the inner ear after radiotherapy and to investigate the protective effect and underlying mechanism of RvE1 using mouse models. METHODS: A dose of RvE1 was delivered by intraperitoneal injection to mice before irradiation. Changes in the auditory brainstem response (ABR), relative balance ability, inner ear morphology and the expression levels of inflammatory factors in the inner ear were analyzed on days 7 and 14 after irradiation and compared among different experimental groups. RESULTS: Changes of ABR and relative balance ability showed the inner functions of experimental mice presented severe damage after irradiation, but the damage was significantly alleviated after RvE1 pretreatment compared to irradiation alone. Morphological analysis of the inner ear showed severe damage to the cochlea and vestibule after irradiation. In contrast, damage to the cochlea and vestibule was significantly reduced in the RvE1-pretreated group compared to that in the irradiation alone group. Along with these functional and morphological changes, the mRNA expression level of anti-inflammatory factors interleukin-2 was significantly increased, while those of proinflammatory factors interleukin-6 and tumor necrosis factor-α were significantly decreased in the inner ear of mice after RvE1 pretreatment compared to irradiation alone. CONCLUSIONS: We believe that inflammation induced by irradiation is involved in the damage to the inner ear caused by radiotherapy, and that RvE1 reduces the damage caused by irradiation to the inner ear by regulating the induced inflammatory response.

Effects of Epstein-Barr virus infection on liver function in children.

OBJECTIVE: In order to analyze the effect of Epstein-Barr (EB) virus infection on the liver function of children, the age and season of children susceptible to EB virus were analyzed in this study. METHODS: In this study, 118 children with EB infection from Cangzhou Central Hospital were selected as the subjects, and 10 children with normal liver function were selected as the control group. Compared with normal children, the changes of blood cells, immune cells and indicators related to liver function in patients with EB virus infection were compared, and the expression of EB virus -DNA in patients' peripheral blood was analyzed. Immunohistochemistry was used to analyze the location and changes of CD4+T lymphocytes, CD8+T lymphocytes, and granzyme B cells in the liver of the patients. And changes in liver tissue were studied by in situ hybridization. RESULTS: It was found that children in early childhood (1-3 years old) were the most susceptible group, and summer and autumn were the most susceptible seasons. Compared with normal children, the number of red blood cells and white blood cells in patients infected with EB virus increased, while the number of platelets decreased, but the difference was not significant. The liver function indexes of Alanine transaminase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), total bilirubin (TBIL), and lactate dehydrogenase (LDH) increased after infection. The content of CD4+T lymphocytes decreased, while that of CD8+T lymphocytes increased. The level of immune factor IgG increased significantly (P<0.01), granzyme B cells were positive compared to that of normal humans, and positive lymphocytes containing EBER appeared. CONCLUSION: Therefore, EB virus may affect liver function by acting CD8+T lymphocytes in children.

Effect of garlic powder on acrylamide formation in a low-moisture model system and bread baking.

BACKGROUND: Acrylamide (AA) is of concern worldwide because of its neurotoxicity, genotoxicity and reproductive/developmental toxicity. Consequently, methods for minimizing AA formation during food processing are vital. RESULTS: In this study, the formation and elimination of AA in an asparagine/glucose low-moisture model system were investigated by response surface methodology. The effect of garlic powder on the kinetics of AA formation/elimination was also evaluated. The AA content reached a maximum level (674.0 nmol) with 1.2 mmol of glucose and 1.2 mmol of asparagine after heating at 200 °C for 6 min. The AA content was greatly reduced with the addition of garlic powder. Compared to without garlic powder, an AA reduction rate of 43% was obtained with addition of garlic powder at a mass fraction of 0.05 g. Garlic powder inhibited AA formation during the generation-predominant kinetic stage and had no effect on the degradation-predominant kinetic stage. The effect of garlic powder on AA formation in bread and bread quality was also investigated. Adding a garlic powder mass fraction of 15 g to 500 g of dough significantly (P < 0.05) reduced the formation of AA (reduction rate of 46%) and had no obvious effect on the sensory qualities of the bread. CONCLUSION: This study provides a possible method for reducing the AA content in bread and other heat-treated starch-rich foods.

Spontaneous formation of hierarchical wrinkles in Cr films deposited on silicone oil drops with constrained edges.

We report on the spontaneous formation of hierarchical wrinkling patterns in Cr films deposited on silicone oil drops with constrained edges. The appearance of the wrinkling patterns is strongly dependent on the film thickness and the size of the silicone oil drop. Because the Cr film at the drop edge is constrained due to the strong adhesion between the film and the glass surface, the wrinkle wavelength merely depends on the distance starting from the drop edge. When the distance increases, the wavelength increases quickly first, and then it slows down gradually in compliance with a simple power law. The evolution of the wrinkle amplitude is similar to that of the wavelength, but it is also closely related to the film thickness and the oil drop size. Based on the fact that the silicone oil is polymerized to form an elastic layer during deposition, the formation and evolution of the hierarchical wrinkling patterns have been analyzed in detail.