Hydrogels that electronically respond to mechanical changes can be used as strain sensors. However, these systems usually require external power to convert changes in strain into electrical signals. ...Here, a self-powered strain sensor is developed based on a gelatin-based hydrogel and a galvanic cell. In the hydrogel matrix, hydrophobic interactions and hydrogen bonding between tannic acid and gelatin give the prepared hydrogel great potential for elongation (1600%). The hydrogel also has a rapid self-healing ability (within 0.65 s) and high self-healing efficiency (95%). The hydrogel operates as an efficient electrolyte material and forms a hydrogel battery when assembled with a thin layer of zinc and an air electrode. This device had excellent tolerance to large compressional strain without sacrificing open-circuit voltage. On the basis of this hydrogel battery, we fabricated a self-powered strain sensor by connecting the hydrogel battery to a fixed resistor to form a closed loop. By converting its chemical energy into electrical energy, the self-powered sensor efficiently converted resistance changes, caused by stretching or compression of the hydrogel, into changes in the voltage output signals without external power. Owing to the stretchability of the hydrogel, the self-powered sensor exhibited good response and flexibility. Self-healing and continuous cycling tests confirmed the long-term stability of the device. These properties suggest that our self-powered sensor has a potential for applications to portable and wearable electronic devices.
For the first time, boronic acid–modified polymer dots (B-PDs) were fabricated by a “synthesis-modification integration” route using polyethylenimine (PEI) and phenylboronic acid as precursors. Under ...optimized preparation conditions, the B-PDs exhibited an average size of 2.2 nm, good water solubility, and high fluorescence quantum yield of 8.69%. The B-PDs showed reversible fluorescence response in acid solutions (blue emissions) and alkaline solutions (green emissions). The fluorescence emissions of B-PDs demonstrated an obvious red shift with varying the pH value from 1 - 13. Moreover, glucose could assemble on the surface of B-PDs due to the reversible reaction between boronic acid and
cis
-diols, which resulted in a blue shift of emission wavelength and an obvious increase of FL intensity at λ
ex
= 380 nm based on the aggregation-induced enhancement effect. The glucose sensing method was thus developed in the range 0.0001 - 1.0 mol L
−1
. Applications to real human blood and glucose injection samples demonstrated satisfactory results. The B-PDs based on the analytical method display good selectivity, wide detection range, and simplicity in preparation and detection, implying promising applications as a practical platform for biosensing.
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This paper explores the applicability of cryogenic permanent magnet motor stator materials for LNG pumps. First, this study selected four kinds of silicon steel sheets for motor stators tested at ...room temperature and ultra-low temperature and obtained the magnetization characteristics and loss characteristics of the four silicon steel sheets at room temperature and ultra-low temperature. Then, through a comparative analysis of experimental data, the applicability of silicon steel sheet material in an ultra-low-temperature environment was verified. Finally, the improved methods of the basic iron loss model of silicon steel sheets and the basic iron loss model of motors were proposed, and the accuracy and feasibility of the improved models were verified.
Rumor, with the fast speed of transmission, may bring us panic, even economic loss. Thus, it is significant for us to take effective steps to control the rumor spreading. Unfortunately, most of the ...existing works ignore that the spreading probability is not a constant, but depends on the number of spreaders currently. That is to say, the more spreaders, the larger spreading probability. In order to overcome this shortcoming, in this paper, we propose a novel susceptible–infected–removed (SIR) rumor spreading model with the influence mechanism, called SIR-IM, which first incorporates the number of current spreaders into the spreading probability. Then, it employs time function to describe the rate of people from spreader to stifler as time goes on. Moreover, we not only derive mean-field equations to describe the dynamics of our SIR model, but also give theoretical analysis. Numerical simulations are conducted on social networks, which show that the influence mechanism can accelerate the rumor spreading.
Gastric carcinoma is a highly malignant tumor that still lacks effective molecular targets. Heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) is an essential oncogenic driver overexpressed in ...various cancers. The potential role of hnRNPA2B1 in oncotherapy has not been revealed because of the absence of active chemical molecules. In this study, we identified the pseudourea derivative XI-011 as a novel hnRNPA2B1 ligand using chemical proteomics. An interaction study indicated that XI-011 could bind the nucleotide-binding domain to disrupt the recruitment of hnRNPA2B1 to the promoter and untranslated region of the murine double minute X (MDMX) gene, thereby inhibiting its transcription. In addition, chemical targeting of hnRNPA2B1 recovered inactivated p53 and enhanced the therapeutic efficacy of apatinib in vivo. This work presented a novel strategy to restore p53 activity for the treatment of gastric cancers via chemically targeting hnRNPA2B1.
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•Our study identified XI-011 as a heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) ligand that binds the RRM1 domain.•Disrupting the hnRNPA2B1-nucleic acid interactions was an effective means to inhibit the transcription of MDMX.•We presented that targeting hnRNPA2B1 to regulate the MDMX-p53 axis is a promising strategy in gastric cancer treatment.
Autonomously following a man-made trail in the wild is a challenging problem for robotic systems. Recently, deep learning-based approaches have cast the trail following problem as an image ...classification task and have achieved great success in the vision-based trail-following problem. However, the existing research only focuses on the trail-following task with a single-robot system. In contrast, many robotic tasks in reality, such as search and rescue, are conducted by a group of robots. While these robots are grouped to move in the wild, they can cooperate to lead to a more robust performance and perform the trail-following task in a better manner. Concretely, each robot can periodically exchange the vision data with other robots and make decisions based both on its local view and the information from others. This paper proposes a sensor fusion-based cooperative trail-following method, which enables a group of robots to implement the trail-following task by fusing the sensor data of each robot. Our method allows each robot to face the same direction from different altitudes to fuse the vision data feature on the collective level and then take action respectively. Besides, considering the quality of service requirement of the robotic software, our method limits the condition to implementing the sensor data fusion process by using the "threshold" mechanism. Qualitative and quantitative experiments on the real-world dataset have shown that our method can significantly promote the recognition accuracy and lead to a more robust performance compared with the single-robot system.
The propagation of rumor has become a common phenomenon in social networks. Studying the dynamic propagation of rumor can help locate the key points to control rumor propagation. To further research ...the internal motivation of state transition, a corrector-ignorant-spreader-weakener (C-SIW) model is proposed in this paper. When the individual changes state to transmit rumor, the neighbor may have a significant impact on rumor propagation. Considering the point, this paper constructs a function to describe the propagation rate, which relates to the state of neighbors and the reputation of the spreader. In addition, perception from life also can cause individual state changes. Based on the above fact, the links from the spreader and the weakener to the corrector are added to describe the perception mechanism. Then, combining the derived average field equations, the steady state of the model is analyzed and verified in experimental simulation. Moreover, the experimental results on different networks show that the perception mechanism reduces the rumor influence. Besides, the variable propagation rate can position the fast-growing stage of rumor propagation more accurately and facilitate the control of rumor propagation.
Low temperature high-speed motors can achieve low temperature and high viscosity fluid media efficient transmission, meanwhile, excessive friction loss and temperature rise issues are addressed. In ...this paper, a 30kw low-temperature and high-speed permanent magnet motor prototype is implemented as the research object. Three stator axial cooling structures are proposed to effectively control the motor temperature rise. First, the discussion focuses on the friction loss in the air gap and its related influencing factors; at the same time, the effect of different axial cooling structures on the friction loss in the air gap is also considered. Secondly, a calculation method of axial viscous friction loss based on the principle of fluid force equilibrium is proposed in the paper, the variation law of the structure size influence on axial friction loss is also given. Based on the quantitative calculation of axial friction loss, the final structure size is determined by synthesizing the variation of different size structures stator iron loss. Finally, the physical model of the three-dimensional fluid-thermal coupling calculation on the analysis object is established by means of finite element analysis, and the stator temperature rise distribution is calculated.
The construction of integrated energy systems can help improve energy efficiency and promote global energy transition. However, in recent years, the occurrence of extreme natural disasters has ...brought certain threats to the safe and stable operation of the integrated energy system. Thus, it is necessary to improve the ability of the integrated energy system to resist disasters, reduce disaster losses, and restore energy supply as soon as possible, i.e., improve its resilience. Considering the influence of pre-disaster prevention measures and disaster-time operational measures on system disaster resilience and the correlation between the two, this paper proposes a system hardening strategy based on three-layer robust optimization. The upper layer formulates the optimal hardening strategy of the system before the disaster event occurs, the middle layer identifies the failed elements in the worst disaster situation, while the lower layer realizes the system operational optimization by coordinating the energy storage charging and discharging plan of each subsystem. The strategy can reduce the total supply shortage of the integrated energy system and improve the flexibility of the system in the pre-disaster prevention and disaster resistance integration stages.
The P-glycoprotein (Pgp) is a major transporter involved in multidrug resistance (MDR) of cancer cells leading to chemotherapy failure. In our previous study, we demonstrated that the amide ...derivatives of pyxinol are promising modulators against Pgp-mediated MDR in cancer. In the present study, we designed and synthesized novel pyxinol derivatives linked to amino acid residues. We evaluated MDR (paclitaxel (Ptx) resistance) reversal potency of forty pyxinol derivatives in KBV cells and analyzed their structure-activity relationships. Half of our derivatives sensitized KBV cells to Ptx at non-toxic concentrations, among which the pyxinol compound bearing a methionine residue (3c) exhibited the best activity in MDR reversal. Compound 3c was found to possess high selectivity toward Pgp and sensitize the KBV cells to Pgp substrates by blocking the efflux function of Pgp. This manifestation may be attributed to its high binding affinity with Pgp, as suggested by docking studies. Overall, the biological profile and ease of synthesizing these pyxinol derivatives render them promising lead compounds for further development for Pgp-mediated MDR.
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•Forty pyxinol derivatives linked to amino acids were designed and synthesized.•The structure-activity relationships of the MDR reversal activity were described.•Derivative 3c showed higher reversal potency than the reference compound verapamil.•Compound 3c also inhibited the efflux function of Pgp with high selectivity.
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