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Repurposing clinically approved drugs to construct novel nanomedicines is currently a very attractive therapeutic approach. Selective enrichment of anti-inflammatory drugs and reactive oxygen species (ROS) scavenging at the region of inflammation by stimuli-responsive oral nanomedicine is an effective strategy for the treatment of inflammatory bowel disease (IBD). This study reports a novel nanomedicine, which is based on the excellent drug loading and free radical scavenging ability of mesoporous polydopamine nanoparticles (MPDA NPs). By initiating polyacrylic acid（PAA）polymerization on its surface, a “core-shell” structure nano-carrier with pH response is constructed. Then, under alkaline conditions, using the π-π stacking and hydrophobic interaction between the anti-inflammatory drug sulfasalazine (SAP) and MPDA, the nanomedicines (PAA@MPDA-SAP NPs) loaded efficiently (928 μ g mg(−1)) of SAP was successfully formed. Our results reveal that PAA@MPDA-SAP NPs can pass through the upper digestive tract smoothly and finally accumulate in the inflamed colon. Through the synergistic effect of anti-inflammation and antioxidation, it can effectively reduce the expression of pro-inflammatory factors and enhance the intestinal mucosal barrier, and finally significantly alleviate the symptoms of colitis in mice. Furthermore, we confirmed that PAA@MPDA-SAP NPs have good biocompatibility and anti-inflammatory repair ability under inflammation induction through human colonic organoids. In summary, this work provides a theoretical basis for the development of nanomedicines for IBD therapy.

With the development of high-speed railway, researchers pay much attention to the fatigue damage evaluation of critical components. For high-speed railway axles, surface scratches are defined as a main defect. The maximum scratch depth was detected carefully about 128 μm based on EA4T axles. To reveal the negative effect of surface scratches on fatigue performance of EA4T steel, rotating bending fatigue texts were carried out. The results indicated that the critical scratch depth (x0) of EA4T steel is about 10 μm. Less than 10 μm, surface scratch has no obvious effect on fatigue performance of EA4T steel. In addition, to evaluate the operation safety of scratch-affected axles, the geometry and loading type effects were considered. The fatigue limit curve of scratch-affected axles was estimated by Murakami equation. A fatigue estimation method of scratch-affected axles was proposed based on three-dimensional Kitagawa-Takahashi diagram that can be used in the maintenance and evaluation of damaged high-speed railway axles.

The construction of novel photosensitizer for effective reactive oxygen species generation has attracted extensive interest, in particular the design of a new photosensitizer with long excitation wavelength remains challenge. In this paper, we design a novel two-photon active Ruthenium(II) complex (RuL1) based on donor-acceptor configuration ligand. Notably, benefiting from the coordination of Ru ion, the electron transfer between donor and acceptor moiety gave rise to enhanced two-photon activity and prolonged excitation wavelength. The results showed that RuL1 exhibited excellent two-photon activity under near-infrared light excitation (920 nm), which provided a potential platform for photodynamic therapy in “therapeutic window”.

Silicosis is characterized by inflammation and pulmonary fibrosis due to long-term inhalation of crystalline silica (SiO2). To clarify the role of macrophage polarization in the inflammatory response of silicosis, we used iTRAQ-coupled 2D LC–MS/MS to study the change in the secretome in RAW264.7 macrophages. We successfully screened 330 differentially expressed proteins, including 120 proteins with upregulated expression and 210 proteins with down-regulated expression (p

The development of electronic-skin (e-skin) with artificial tactile-perception is crucial for emerging artificial-intelligence systems. However, considering the relatively simple function of existing e-skins, their performances still have much room for improvement. Here, a cuttable, transparent, stretchable, and lightweight e-skin that functions on the basis of the triboelectric effect is demonstrated. Well-designed micro-gaps are introduced to make the e-skin respond sensitively to various mechanical stimulations, including pressing, stretching, folding, and twisting. Ag nanowires coated with graphene quantum dots are employed as the electrode, as well as the friction layer, to increase the sensitivity to external mechanical stimulations. Self-powered, smart, artificial fingers with tactile sensation to monitor the actions of the fingers were fabricated to demonstrate the potential application of our newly developed e-skin. The architecture and the material system of the device demonstrated in this work will promote the development of human-machine interfaces and intelligent machines.

The ability to combine the color-tunability capability of natural organisms with a memory function in a single device is highly desired and holds promise for potential applications such as intelligent artificial skin and human-machine interfaces. In this work, we propose a universal strategy to realize color-tunable skin with the compound function of memory by ingeniously integrating a memristor interface into a flexible quantum-dot light-emitting device. The devices developed using this strategy have multiple responses to electrical and light stimulations and can easily change their color over a wide range from red to green. Moreover, these color-tunable devices can mimic the unique function of “once bitten, twice shy” to enhance self-protection, and their color tunability is consistent with the memory-forgetting curve proposed by psychologists.

In this work, rotating bending fatigue, scanning electron microscope in-situ fatigue, pre-fatigue (and post-fatigue) electron backscatter diffraction tests were carried out for rolled Ti–6Al–4V alloys. The macrozone sizes and orientations of the materials were classified and the effect of macrozones on fatigue cracking behavior and fracture mechanisms was studied. The results indicated that intra-granular fracture was dominated in the process of crack propagation. Basal and prismatic slip systems were favored for the macrozones whose crack paths were straight and zigzag, respectively. Multiple active slip systems can also induce the fatigue crack deflections inside grains. Moreover, fatigue crack propagation rate, threshold stress intensity factor range (ΔKth) and fracture toughness (KIC) were measured for different kinds of macrozones. For the macrozones favorably orientated for prismatic slip, their crack propagation resistance and ΔKth were excellent. However, the KIC values for different macrozones were similar. Finally, the effect of macrozone orientations on fracture mechanisms (cleavage and plastic fracture) was discussed through a combination of Schmid factor, active slip systems and the Δθ angle (between ɑ-Ti phase (0001) plane normals (c-axes) and cyclic load directions). The Δθ is an adequate parameter to predict the fatigue fracture modes.

The performance of perovskite quantum dot light-emitting diodes (PeQLEDs) has been rapidly enhanced recently, but the devices are still stuck in the stage of using small-scale solution processes, such as spin-coating. In this work, we report the realization of high performance PeQLEDs by using inkjet printing technique. We demonstrate the preparation of a printable perovskite quantum dot ink by using a hybrid solvent consisting of high boiling solvent dodecane and low boiling solvent n-octane. A universal strategy for eliminating coffee rings during inkjet printing of perovskite inks is developed based on the modulation of ink formulation, and the stacking model of perovskite quantum dot in a pixel pit structure is proposed. The inkjet-printed PeLEDs exhibit a low turn-on voltage of 2.7 V, a brightness of 10992 cd/m2 at 6.6 V and a maximum current efficiency of 8.67 cd/A, which is by far the highest value reported for inkjet-printed PeLEDs. The results pave a way for future realization of high performance pixelated PeLED displays with inkjet printing technique.

Hypertensive disorder in pregnancy (HDP) refers to a series of diseases that cause the hypertension during pregnancy, including HDP, preeclampsia (PE) and eclampsia. This study screens differentially expressed proteins of placenta tissues in PE cases using 2D LC-MS/MS quantitative proteomics strategy. A total of 2281 proteins are quantified, of these, 145 altering expression proteins are successfully screened between PE and control cases (p

In this work, we demonstrated the field emission properties of few layer molybdenum disulphide (MoS 2 ) nanosheets synthesized by a hydrothermal method. Structural investigation indicates the as-synthesized MoS 2 layers were two dimensional few layer nanosheets with a sharp atomic edges. The field emission properties of the MoS 2 nanosheets were investigated and the results indicate that the MoS 2 nanosheets had an excellent field emission performance with turn on field of 1.0 V/μm, threshold field of 2.1 V/μm, and a field enhancement factor of 9880. Furthermore, the emission current shows the stability over 2 h of continuous operation. The as-synthesized MoS 2 few layer nanosheets hold potential for application in next-generation field emission devices.

In the present work, selective laser melted (SLM) AlSi10Mg samples were used in rotational bending fatigue, scanning electron microscope in-situ fatigue and nanoindentation tests. The effects of building directions (0°, 15°, 45° and 90°) and molten pool boundaries (MPBs) on the fatigue performance and crack propagation behavior of the AlSi10Mg samples were studied. The results indicated that the SLM samples (from 0° to 15° building directions) were in high fatigue performance range. The fatigue fracture parameters (fatigue strength, threshold stress intensity factor range and fracture toughness) of the 0° and 15° samples were higher than those of the 45° and 90° samples. Moreover, the differences of elasticity modulus and hardness between the MPBs and molten pool cores were identified. Under cyclic loads, the mechanical property differences resulted in the MPBs severe strain concentration and plastic deformation. By finite element simulations, the fatigue crack propagation behavior of the SLM samples can be explained. Finally, the crack aspect ratios (a/b) were measured from fracture surfaces. The building directions had no obvious impact on the ratio of a/b whose constant values (a > 300 μm) were about 0.45–0.60.

Additive manufacturing-selective laser melting (AM-SLM) technology for Ti6Al4V alloys has been industrialized and widely used for complex components in recent decades. However, with the effect of AM defects (especially the AM internal defects), the quantitative evaluation of the SLM specimen fatigue limits is difficult but necessary. In the present work, lots of high cycle fatigue data of the SLM Ti6Al4V alloy were provided. To estimate the fatigue limits of the specimens whose fatigue cracks initiate from the SLM internal defects under vacuum-like condition, the linear relation between the Ti6Al4V alloy threshold stress intensity factor range and the logarithmic of vacuum pressures was first identified. Based on the physical mechanisms, a new fatigue limit prediction model was presented. Moreover, the fatigue crack propagation behaviour and deformation mechanisms were discussed by using in-situ scanning electronic microscope and transmission electron microscope observation technologies. The results indicate that, for SLM Ti6Al4V alloy fatigue short cracks, inter-granular fracture is more common. The intersecting slip crack propagation behaviour of crack tips is identified. A zigzag crack path can be observed. Finally, with the increase of crack lengths, intra-granular crack propagation is predominant.

Zinc oxide (ZnO) nanoparticles (NPs) are extensively adopted material to be used as efficient electron transport layer (ETL) in quantum dot light emitting diodes (QLEDs) due to their suitable properties of high electron mobility, good stability, and easy processability. However, because of the naturally high work function of ZnO NPs, the electrons can be spontaneously transferred at the quantum dot/ZnO interface. In addition, the enormous difference in electron and hole mobility can lead to interfacial exciton quenching and unbalanced charge injection. In this paper, the strategy of replacing the ZnO in QLEDs with Mg and polyvinylpyrrolidone (PVP) inorganic-organic hybrid co-doped ZnO NPs are introduced. The energy band structures of ZnO NPs are tailored by tuning the concentrations of Mg, resulting in a significant suppression of the spontaneous charge transfer at the quantum dot/ETL interface. Furthermore, the surface quenching sites and the electronic mobility of ETL were adjusted via PVP doping. The proposed method significantly enhances the current efficiency and external quantum efficiency to 16.16 cd/A and 15.45%, respectively, an improvement of about 2.5-fold compared to the devices with pure ZnO NPs.