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Background: Elevated tumor necrosis factor alpha (TNF-α) expression is correlated with the progression of intervertebral disc degeneration (IVDD). Progranulin binding to tumor necrosis factor receptor (TNFR) and its derivative Atsttrin are effective for treating inflammatory arthritis. We hypothesize that Atsttrin has a protective effect in IVDD through different roles of TNFR receptor type 1 (TNFR1) and TNFR receptor type 2 (TNFR2) in degenerated discs. Methods: IVDD models were established in TNFR1−/−, TNFR2−/− mice and their control littermates. Nucleus Pulpous (NP) samples from human patients and IVDD murine models were evaluated by X-ray, micro-MRI, μCT, histological staining and immunofluorescence staining. NP cells isolated from wild-type (WT), TNFR1−/− and TNFR2−/− mice were treated with TNF-α or Atsttrin and then assayed by Western blotting, qRT–PCR, and ELISA. Results: TNFR1 and TNFR2 expression was significantly elevated in the disc tissues of both human patients and IVDD murine models. TNFR1 knockout contributed to reduced disc degeneration. In contrast, TNFR2 knockout was associated with enhanced IVDD severity, including degraded cellular composition, increased cell apoptosis and elevated vertebral destruction. Atsttrin protected against IVDD in WT and TNFR1−/− mouse models but had no effect in TNFR2−/− IVDD models. Additionally, in vitro NP cell-based assays demonstrated that TNF-α-stimulated catabolism and Atsttrin-activated anabolism depended on TNFR1 and TNFR2, respectively. Conclusion: TNFR1 is associated with the degenerative progression of IVDD, while TNFR2 contributes to the protective effect on the discs. Atsttrin protects against IVDD at least partially by inhibiting the TNFα/TNFR1 inflammatory/catabolic pathway and activating the TNFR2 protective/anabolic pathway. The translational potential of this article: This study demonstrates that TNFR1 and TNFR2 have disparate roles in disc degeneration and hlights the potential use of Atsttrin as a therapeutic agent against IVDD in mice.

Mercury (Hg), a kind of heavy metal pollutant, has a great impact on the environment and human health. The highly efficient technology for Hg removal has attracted widespread attention from researchers. In this study, the coal gasification slag (CGS) and the slag after sorting were used as sorbents, and the Hg0 removal performance of the sorbents were investigated through the fixed-bed reactor and entrained flow reactor. The characterization methods such as N2 adsorption-desorption, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) were performed to analyze the physical and chemical characteristics of the sorbents. According to the results of fixed-bed Hg0 removal experiment, the Hg0 removal efficiency of the origin slag (OS) and high carbon slag (HCS) could maintain more than 91% at 60–120°C. The high ash slag (HAS) showed the highest Hg0removal efficiency of 97% at 60°C, which was greatly affected by the Hg0 removal temperature. The Hg-TPD (Hg-temperature program desorption) and XPS results indicated that the chemisorbed oxygen on the sorbent participated in the Hg0 oxidation process with HgO formed on the surface of the sorbent. According to the results of entrained flow Hg0 removal experiments, the Hg0 removal efficiencies of OS and HCS were 56% and 57% at C/Hg ratio of 40000 and the Hg0 removal temperature of 60°C, respectively. When the C/Hg ratio was 80000 and the Hg0 removal temperature was 60°C, the Hg0 removal efficiencies of OS and HCS were 100% and 82%, respectively.

Aims Bone marrow mesenchymal stem cells (BMSCs) show great potential in clinical applications such as in intervertebral disc degeneration. Nevertheless, environmental stress during the BMSC transplant or in the injured tissues is a catastrophic factor that causes cell toxicity and poor survival of BMSCs. Mitophagy plays a vital role in maintaining cellular homeostasis and defending against oxidative stress because this process could control mitochondrial quality and quantity by eliminating dysfunctional or damaged mitochondria that can cause cell death. However, the accurate mechanisms of mitophagy in protecting BMSCs against the harshness of oxidative stress remain largely unknown. Main methods BMSCs were treated with H2O2 for various time periods. Mitophagy response was evaluated through the expression levels of LC3-II, p62 and mitophagosomal formation by using Western blot and fluorescence analysis. Cell apoptosis was examined by flow cytometry and TUNEL assay. The interactions of mitophagy and apoptosis and the possible signalling pathways were investigated through the co-treatment of mitophagy inhibitor or mitophagy activator with H2O2. Key findings Oxidative stress rapidly facilitated mitophagy through JNK at an early stage but decreased mitophagy and increased apoptosis at a late stage. Furthermore, mitophagy inhibition significantly enhanced the apoptosis in the cells treated by H2O2. Significance Induced mitophagy may play pivotal roles in protecting cells against oxidative stress in BMSCs.

To decrease the separation density of a dense-medium cyclone by using an online control method, a coaxial coil was placed outside the lower cone position of the dense-medium cyclone, and a separation test of coal with a size of 0–3 mm was performed in a coaxial magnetic field. Subsequently, the density composition of the separation products was determined through a float-and-sink analysis. Further, the magnetic force of the dense-medium particles in a magnetic field generated by the coil was analyzed through the Ansoft software. The results showed that dense-medium particles were attracted into the underflow by the downward axial magnetic field force. Therefore, the separation density of the dense-medium cyclone can be decreased in the magnetic field created by the coil with large passing currents (i.e. 12.5–20 A). Hence, this study may provide a new method to control the separation density of dense-medium cyclones, which has a considerable significance to improve the automation of coal preparation plants.

For cooling system, liquid metal (LM) have attracted many attentions as an excellent coolant. In this study, we propose a superior liquid metal cooling blade dissipator with twin stage electromagnetic pumps (EMPs), whose thinnest dimension was only 4 mm. The coupling model is utilized to solve the distribution of Lorentz force and the field of velocity and temperature simultaneously in the COMSOL multi-physics software, and the validity of numerical model was verified by experimental data. It is demonstrated that the efficiency of twin stage EMPs was obviously higher than that of single stage of EMP at the same input power theoretically. The Nusselt number at the heater is calculated under the different driven current and heating power. It has been found that there was no obvious change for Nusselt number. Also it can be concluded that the superior property of suppressing thermal shock and high performance-cost ratio were presented.

Automatic vessel segmentation is a key step of clinical or pre-clinical vessel bio-markers for clinical diagnosis. In previous research, the segmentation architectures are mainly based on Convolutional Neural Networks (CNN). However, due to the limitation of the receipt of field (ROF) of convolution operation, it is difficult to further improve the accuracy of the CNN-based methods. To solve this problem, a Squeeze-Excitation Transformer U-net (SETUnet) is proposed to break the ROF limitation of CNN. The proposed squeeze-excitation Transformer can introduce the self attention mechanism into the vessel segmentation task by generating a global attention mapping according to the entire vessel image. To test the performance of the proposed SETUnet, the SETUnet is trained and tested on several public vessel data-sets. The results show that the SETUnet outperforms several state-of-the-art vessel segmentation neural networks, especially on the connectivity of the segmented vessels.

In this study, the electroflotation of quartz and magnetite with cationic collector dodecylamine (DDA) and anionic collector sodium oleate (NaOL) were investigated to gain a better understanding of the electroflotation process and identify methods to improve it. An interesting phenomenon accompanied with obvious promotion (NaOL is used as collector) and inhibition (DDA-HCl is used as collector) of quartz flotation was observed after electrolysis. The obvious promotion arouse from the supply of the metal cations as active site for the adsorption of negatively charged group and increase active collecting species ionic forms RCOO- and (RCOO)22–. Conversely, the obvious inhibition originated from the decrease of the active collecting species RNH3+ and (RNH3)22+. An obvious inhibition phenomenon was observed after the electrolysis for the magnetite. This is because the active collecting species RNH3+, (RNH3)22+, RNH2·RNH3+ and RCOOH molecule decreased significantly after electrolysis. Furthermore, a comparison test between the regular flotation and electroflotation was conducted in the reverse flotation of magnetic separation concentrate. Compared with the regular flotation process, electroflotation flotation was characterized by simple reagent regime (without pH regulator and activator) and moderate conditions (natural pH), which had mild operation condition superiority. Moreover, the flotation product index of electroflotation can be better through slightly adjusting the reagent regime, and it can be certain that electroflotation is an effective process in the reverse flotation of magnetite. These findings provided a novel perspective for understanding the electroflotation process.

Operational efficiency is an important bottleneck in the industrialization of apple picking robots. The action planning of grasping and picking is key to improving the operational efficiency of picking robots. In this study, first, from the perspective of grip stability, the grasping positions of a three-finger end-effector were planned in two cases to determine an optimal three-finger grip posture: one that is parallel to the apple stem–calyx axis and the other being centripetal to the apple equatorial plane. Second, based on the gripping posture parallel to the apple stem-calyx axis, four picking patterns were designed: vertical pull, horizontal pull, vertical rotation, and rotation–horizontal pull. With the horizontal displacement, vertical displacement, and rotation angle as the main factors influencing the picking process, it was found through ABAQUS simulation software and the response surface analysis method that the rotation–horizontal pull pattern with the combination of horizontal displacement and rotation angle yields the minimum separation force for apple piking. With the three-fingered hand in the optimal grasping posture parallel to the stem–calyx, the four picking patterns were tested on a dedicated apple picking experimental device equipped with a grip force acquisition sensor, and the test results showed that the average three-finger grip force required for rotary tug-pull picking was the lowest (10.33 N). The proposed rotation–horizontal pull pattern with the three-finger grip posture was proven to be the best pattern for apple picking. The results of this study provide a theoretical basis for further research on apple picking robots.

Dodecylamine (DDA) can only be used with acidification in the reverse flotation of iron ore. To solve this problem, this paper proposed a novel water-in-oil microemulsion with DDA prepared using one or two of AEO-3, OP-10, and Tween-80 & Span-80 as the surfactants, 2-octanol as the cosurfactant, and DDA and kerosene as the oil phase. The freezing point, surface tension, droplet size distribution, and zeta potential were determined for the DDA microemulsion. The results showed that the freezing point of the produced DDA microemulsion can be reduced to –12.5 °C. Moreover, the surfaces of its droplets dispersed in aqueous solution are positively charged at pH values less than 10.0. The flotation performance of the DDA microemulsion was investigated by flotation tests. From the results, DDA microemulsion exhibited good dispersibility and surface activity, thereby confirming its ability to effectively reduce air–water interfacial tension. In addition, it was found to have good adaptability to temperature and pulp pH, yielding a magnetite concentrate with 68.54% Fe and 3.60% SiO2 from magnetite with 64.93% Fe and 9.12% SiO2 using 45 g/t DDA microemulsion. Therefore, the proposed DDA microemulsion can be used as an efficient collector in the reverse flotation of magnetite.

A new method for synthesizing phenanthridines by photocyclization has been established. This method does not require inert gas protection, does not require transition metal catalysts and is environmentally friendly, efficient and convenient. It is proposed to use (E)-N,1-diphenylformimines as substrates to synthesize phenanthridine and its derivatives by ultraviolet light, which provides a new synthesis route for further research on the synthesis of phenanthridines by photocyclization. Eight new phenanthridine compounds were synthesized. The confirmation of their structures provides a material basis for further study of their properties and tapping of their potential for applications. The establishment of this method further broadens the synthetic pathways of phenanthridine compounds.

In this study, five types of surfactants including non-ionic lipophilic surfactant Span series surfactant, non-ionic hydrophilic surfactant Tween and OP series surfactant, characteristics of both anionic and hydrophilic surfactant NaOL and triethanolamine oleate (named as OL series for short), characteristics of both cationic and hydrophilic surfactant AC1201 and AC1205 (named as AC series for short) were chosen as research subjects to investigate the relationship between the structure and synergistic ability of surfactants, focusing on the adsorption of the typical cationic collector dodecylamine (DDA) and surfactant mixture at liquid/air and solid/liquid interface to investigate the application potential of structure in the development of an effective surfactant to apply for quartz flotation. Flotation experiments, surface tension measurements, microcalorimetric experiments, interaction parameter calculation and Fourier Transform Infrared Spectroscopy (FTIR) analysis were used to analyze the characteristics of different DDA/surfactant systems and the interaction mechanism between quartz and collector mixture. The flotation results indicated that the synergistic capacity of these surfactants was in the following ranking: AC > OP > Tween > Span > OL. AC1201 showed a stronger synergistic ability than the other surfactants, accompanying with a recovery promotion over 20% compared with pure DDA. The physicochemical properties including surface activity parameters, the micelles and interfacial compositions, and interaction parameters were evaluated according to the theory of regular solutions. The surface tension and critical micelle concentration of the mixture solution decreased with the addition of the surfactant. According to the basic Rubingh equations, the interaction parameter of these surfactants was in the following ranking: OL > Span > OP > Tween > AC, indicating that the flotation recovery of quartz was negatively correlated with the interaction parameters. While there was a positive correlation between the interaction heat changes obtained from microcalorimetry and the trend from the flotation experiments. The obtained results demonstrated that it should be chosen this type of surfactant, which can be able to intensify collector adsorption at the solid/liquid interface. AC1201 has a potential for industrial application in the flotation of quartz.

A novel combined reagent dodecylamine (DDA)–2-octanol–kerosene was employed to overcome the problems associated with DDA, that is, DDA has a high freezing point and needs to be acidified with hydrochloric or acetic acid when it is used for flotation. The analysis of the basic physical properties of the agent showed that DDA–2-octanol–kerosene had significant advantages in freezing point and dispersibility and its freezing point can be reduced to below 0 °C. From the flotation results of magnetite, it can be seen that DDA–2-octanol–kerosene has a better selectivity. Response Surface Methodology based on a three-level, three-variable Box–Behnken design (BBD) was employed to define the quadratic relationship between the recovery of quartz and the composition of the mixed agent. The results indicated that the recovery of quartz increased with the increase of DDA or 2-octanol dosage, however, kerosene had a marginal positive effect on the recovery of quartz when the amount of kerosene was less than 0.76 times that of DDA and otherwise a negative effect. This study provides a new method and technical support for its industrial application for the reverse flotation of iron ore for the combination of agents in the field of iron ore flotation. And allows for a deeper macro-level understanding of the interaction between the DDA–2-octanol–kerosene ternary mixed agents.

This research explores why customers who experience service failure are willing to complain directly to service providers but unlikely to switch to other service providers. We bring in the concept of psychological climate for communication safety (PCCS) to the service failure context and explore how customers’ perception of the social environment as open and supportive for communication affects their complaint and service switching intentions and behaviors. We further identify customer harmony enhancement as an important personality trait predictor of PCCS. Based on two field studies and one scenario-based experimental study, our findings consistently show that PCCS mediates the positive effect of customer harmony enhancement on customer complaint intentions. Customer harmony enhancement exerts a positive indirect effect on customer complaint behavior serially through PCCS and customer complaint intentions. However, our findings relating to customer service switching intentions are inconsistent across the three studies. Theoretical and practical implications are discussed.