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Synthesis of anion exchange membranes (AEMs) with orientated nano/micro-structure and with tunable ion-channels is of great interest for applications in fuel cells, water electrolyzers, and redox flow batteries. However, there is still a dearth of work in the detailed understanding of anion conductivity from a polymer structure‒property perspective. Herein, we demonstrate an easy and versatile strategy to fabricate highly conductive AEMs. By stretching the AEMs, an improvement in OH− conductivities of AEMs is achieved. The effect of elongation at different water contents on polymer structures and OH− conductivities was investigated by a combination of molecular dynamics (MD) simulation and experimental study, giving insights into macromolecular orientation at the atomic level. The morphological changes, which consist of oriented polymer chains and elongated water clusters, are quantified by a combination of two dimensional small angle X-ray scattering (SAXS), scanning electron microscopy (SEM) and radial distribution functions. Detailed analyses of interatomic distances reveal morphological variations of hydrophilic domains and their interactions with water and OH− under elongation at different hydration levels. Furthermore, the OH− conductivities of our synthesized quaternized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO) AEMs increased significantly after stretching to 20% elongation at all water contents. Specifically, OH− conductivity of stretched QPPO was 2.24 times more than the original AEM at 60% RH. The higher relative increase in OH− conductivity at lower water content may be caused by the lower flexibility of side chains at lower hydrated level. This work verifies the significance of porous and/or oriented AEM structure in the improvement on anion conductivity and water transport efficiency.

Ionic covalent organic framework nanosheets (iCOFNs) with long-range ordered and mono-dispersed ionic groups hold great potential in many advanced applications. Considering the inherent drawbacks of oil-water biphase method, herein, we explore an oil-water-oil triphase method based on phase engineering strategy for the bottom-up synthesis of iCOFNs. The middle water phase serves as a confined reaction region, and the two oil phases are reservoirs for storing and supplying monomers to the water phase. A large aqueous space and low monomer concentration lead to the anisotropic gradual growth of iCOFNs into few-layer thickness, large lateral size, and high crystallinity. Notably, the resulting three cationic and anionic iCOFNs exhibit ultra-high aspect ratios of up to 20,000. We further demonstrate their application potential by processing into ultrathin defect-free COF membranes for efficient biogas separation. Our triphase method may offer an alternative platform technology for the synthesis and innovative applications of iCOFNs.

In this paper, we study a joint service authorization and capacity planning problem for the home health care (HHC) system with demand uncertainty. We formulate the problem as a two-stage stochastic programming with recourse which maximizes the expected total revenue. The service authorization and capacity planning are the mixed binary-and-continuous first stage decisions, and the service hour (resource) allocation is modeled as the second-stage decision which adapts to the demand realizations. The resulting sample average approximation problem (of the stochastic program) could be a large scaled mixed integer linear program. To solve the model in a more scalable fashion, we propose a supergradient-based nested decomposition algorithm that exploits the nice decomposable structure of the problem to cope with the binary and continuous variables separately. The proposed nested decomposition scheme consists of two-layer of decomposition, where the outer decomposition solves for the authorization decision (binaries) with the supergradient cuts and each supergradient can be computed iteratively in the inner decomposition scheme. The proposed nested decomposition algorithm is feasibility-cut-free and is guaranteed to reach the exact optimality in finite steps. Furthermore, we extend our stochastic HHC planning model to a more general framework of Conditional Value-at-Risk (CV@R), and by model transformation with variable change we show that the CV@R model can actually be reformulated in a structure that the proposed nested decomposition scheme can be applied almost directly. Finally, a comprehensive computational study is performed which demonstrates the effectiveness of our model and the performance of the algorithm.

To overcome the issue that the commonly used linear PI controller is not strong in the nonlinear system and cannot be satisfied with the performance requirements of fast and stable speed modulation of PMSM, a new type of exponential convergence law is devised on the basis of the exponential approximation law of conventional sliding mode controller to accelerate the convergence of the Speed control system and improve the jitter problem of the system. Three models of rotational speed controllers built in Simulink are compared in cases of no-load start-up and sudden load addition, and the new exponential reaching law presented in this article can be effective in improving the control performance of the system, strengthening the anti-disturbance capability and robustness of the Speed control system.

Cervical cancer is one of the three most common tumors in women. In this study, we found that ZEB2 was significantly overexpressed in cervical cancer. It was found that that circular RNA circ-0117530 transcribed by ZEB2 was significantly overexpressed in cervical cancer tissues. Circ-0117530 promoted growth, invasion, and migration in cervical cancer cell lines. Dual-luciferase assays showed that that circ-0117530 regulated ZEB1 expression by sponging miR-874. These results suggest that the ZEB family is closely related to the occurrence and development of cervical cancer. Overall, we found that circ-0117530 regulates the occurrence and development of cervical cancer through the miR-874/ZEB1 axis, which may provide a potential new therapeutic target for the treatment of cervical cancer.

Aims: Emerging evidence is demonstrating that rapid regeneration of remnant liver elicited by associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) may be attenuated in fibrotic livers. However, the molecular mechanisms responsible for this process are largely unknown. It is widely acknowledged that the TGFβ1 signaling axis plays a major role in liver fibrosis. Therefore, the aims of this study were to elucidate the underlying mechanism of liver regeneration during ALPPS with or without fibrosis, specifically focusing on TGFβ1 signaling. Approach: ALPPS was performed in rat models with N-diethylnitrosamine-induced liver fibrosis and no fibrosis. Functional liver remnant regeneration and expression of TGFβ1 were analyzed during the ALPPS procedures. Adeno-associated virus-shTGFβ1 and the small molecule inhibitor LY2157299 (galunisertib) were used separately or in combination to inhibit TGFβ1 signaling in fibrotic rats. Results: Liver regeneration following ALPPS was lower in fibrotic rats than non-fibrotic rats. TGFβ1 was a key mediator of postoperative regeneration in fibrotic liver. Interestingly, AAV-shTGFβ1 accelerated the regeneration of fibrotic functional liver remnant and improved fibrosis, while LY2157299 only enhanced liver regeneration. Moreover, combination treatment elicited a stronger effect. Conclusions: Inhibition of TGFβ1 accelerated regeneration of fibrotic liver, ameliorated liver fibrosis, and improved liver function following ALPPS. Therefore, TGFβ1 is a promising therapeutic target in ALPPS to improve fibrotic liver reserve function and prognosis.

Welded hollow spherical joints (WHSJs) are commonly used in reticulated shell structures. Corrosion on the surface of WHSJs can remarkably reduce their compression capacity. Pitting corrosion is a ...

Zeolites have widely been studied because of the better performance as catalysts and supports. However, the zeolites with only micropores have drawbacks in reactivity and selectivity due to limitation of diffusivity. The hollow zeolite fibers (HZF) with hierarchical porosity however can overcome the problem. The HZF can be synthesized by such methods as incorporated substrate removal method, solid-solid transformation method, co-axial electrospinning technology, dry-wet spinning technology, and hollow fiber incorporation method. The unique hierarchical porous structure leads to the great improvement in the diffusion efficiency of reactants. The catalytic zeolite membrane fibers are the most commonly used as they have stronger catalyst stability and higher catalytic selectivity. The HZFs are suitable in catalytic applications such as selective catalysis, CO preferential oxidation, air purification and wastewater treatment. In order that the HZFs can be applied to industrial operations, more research work should be carried out, such as developments of self-assembly pure HZFs, catalytic substrate incorporated HZFs, HZFs with gradient multicomponent zeolites and HZFs with nanoscale diameters.

We investigate the impact of board of directors' foreign experience on stock price informativeness from 2008 to 2016 in Chinese A‐share listed firms. The empirical findings suggest that board of directors' foreign experience has a positive and significant impact on stock price informativeness. By analysing the role of external monitoring factors, our results show that board of directors' foreign experience has a positive and significant impact on stock price informativeness in the absence of external monitoring factors such as audit quality, the cross‐listing of firms, and foreign ownership. Our findings are robust to the use of advanced techniques and the inclusion of instrumental variables. Overall, our study supports the resource dependency theory and the substitutional effect on the relationship between board of directors' foreign experience and stock price informativeness.

Suitable fissures in kernels and the golden yellow color are the desired visual quality to evaluate germinated brown rice (GBR) subjected to drying processing. To improve the visual quality of GBR ...

Achieving high power output from proton exchange membrane fuel cells (PEMFCs) requires efficient proton transport in proton exchange membranes (PEMs). Since proton conductivity is closely related to membrane moisture content, operation at low relative humidity (RH) and elevated temperature has become a critical bottleneck for the practical application of PEMFCs due to severe PEM dehydration. While several strategies have sought to mitigate this, including external thermal and water management, coating of nano-cracked hydrophobic layers and optimization of membrane intrinsic water retention, only partial improvements have been realized. Here, using a membrane formulation of ferrocyano-coordinated poly(4-vinylpyridine) (CP4VP), phosphotungstic acid (PWA) and polysulfone (PSf), novel highly water-retentive PEMs are fabricated via a strong magnetic field. During magnetic-assisted membrane casting, CP4VP and PWA form a microporous Prussian blue analogue (PBA) framework with the new type of Fe–CN–W bonding, which is paramagnetic and is thus simultaneously aligned in the through-plane (TP) direction of the membrane. The neutral PSf membrane component affords mechanical strength to the embedded TP-aligned conducting channels. This new type of microporous PBA framework is highly hydrophilic and proton conductive, with micropores of ∼5.4 A diameter, which act as nano-sponges to absorb only more retentive non-freezable water, effective for proton conduction. These nano-sponges display efficient water absorption and retention at low RH and elevated temperatures, together with a much faster hydration process than the dehydration process. Furthermore, the TP-aligned PBA channels also enable faster water transport to promote PEM proton conduction beyond any previously reported water-retentive membrane. Consequently, the novel nano-sponge-like PEMs exhibit remarkable performance in both ex situ and in situ evaluations, especially at low RH and elevated temperature, largely prevailing over the commercial benchmark Nafion® 212.

Interactive image segmentation can improve segmentation performance using manual intervention. Traditional interactive segmentation methods have unsatisfactory segmentation accuracy for images with complex background. Deep learning-based methods depend on large and accurate annotated datasets. In this paper, we propose an online interactive segmentation method based on graph convolutional network (GCN), which includes the superiorities of these two types of methods. We present a pre-segmentation stage to get an initial segmentation of the image, then propose an interactive GCN (iGCN) module to further improve the accuracy of the initial segmentation. Moreover, iGCN module is trained online without any pre-training burden. Experimental results show that our method outperforms several state-of-the-art methods on GrabCut and Berkeley datasets.

The reinforced concrete-filled steel tube (RCFST) column solves several of the problems of the concrete-filled steel tube (CFST) column in practical engineering applications. Moreover, RCFST has a simple joint structure, high bearing capacity, good ductility, and superior fire resistance. From a structural safety perspective, designers prioritize the creep performance of CFST members in structural design. Therefore, the creep behavior of RCFST columns should be thoroughly investigated in practical engineering design. To study the influence of the creep behavior of RCFST columns under axial compression, this work analyzed the mechanical behavior of composite columns based on their mechanical characteristics under axial compression and established a creep formula suitable for RCFST columns under axial compression. A creep analysis program was also developed to obtain the creep strain–time curve, and its correctness was verified by existing tests. On this basis, the effects of the main design parameters, such as the stress level, steel ratio, and reinforcement ratio, on the creep behavior were determined and analyzed. The creep of the tested composite columns increased rapidly in the early stages (28 days) of load action; the growth rate was relatively low after 28 days and tended to stabilize after approximately six months. The stress level had the greatest influence on the creep of RCFST columns under axial compression, followed by the steel ratio. The influence of the reinforcement ratio on the creep behavior was less. The results of this study can provide a reference for engineering practice.

Objective To clarify the role of miR‐92a in regulating the malignant progression of cervical cancer and its specific molecular mechanism. Methods qRT‐PCR was used to detect the differential expression of miR‐92a in cervical cancer and adjacent tissues. The effects of overexpression of miR‐92a on the proliferation, migration, and invasion of HeLa and SiHa cells were tested. Luciferase assays and rescue experiments were used to investigate the regulatory mechanism of miR‐92a on its downstream gene PIK3R1 and their interaction in the progression of cervical cancer. Results miR‐92a was significantly up‐regulated in cervical cancer tissues. Overexpression of miR‐92a significantly increased the ability of cervical cancer cells to proliferate, migrate, and invade. PIK3R1 was identified as a downstream gene of miR‐92a. In cervical cancer tissues, PIK3R1 was found to be down‐regulated and negatively correlated with the level of miR‐92a. Overexpression of PIK3R1 reversed the promotional effect of overexpressed miR‐92a on the proliferation, migration, and invasion of cervical cancer. Conclusion miR‐92a is up‐regulated in cervical cancer tissues. miR‐92a promotes the malignant development of cervical cancer by negatively regulating PIK3R1., miR‐92a increases expression in cervical cancer tissues and promotes cervical cancer cell proliferation, invasion, and migration.

The replacement of coal gangue for aggregate in concrete can not only reduce the construction cost but also improve the environmental condition. The GFRP-coal gangue concrete-steel tubular (GGCS) columns provide a way to consume the coal gangue. The target of this work is to validate the feasibility of replacing ordinary concrete with coal gangue concrete and investigate the compression behavior of GGCS columns. The nonlinear analysis program of GGCS hollow columns under axial compression was proposed, and the axial compression tests of seven GGCS hollow columns were carried out. The program was verified through experimental results. On the basis of the correctness of the program, the influences of the typical parameters, such as the thickness of the glass fiber tube, the thickness of the steel tube, and the outer radius of the steel tube, on its axial compression performance were systematically analyzed. Finally, the analytical formula for predicting the axial bearing capacity of GGCS hollow column was proposed. The comparison of results indicated that the analytical results agreed well with the experimental results. The axial compression capacity of GGCS hollow columns increased linearly with the increase of the thickness of the glass fiber tube and the steel tube, but not linearly with the decrease of the outer radius of the steel tube. With the increase of the thickness of the glass fiber tube, the constraint effect of the glass fiber tube on gangue concrete was improved. With the increase of the thickness of the steel tube, the stiffness of GGCS hollow column increased. The conclusions of the presented work can provide references for the design and calculation of the GGCS columns.

High-efficiency phosphate removal from wastewater is crucial for protecting environmental stability. In this work, a lanthanum carbonate grafted ZSM-5 adsorbent (LC-ZSM-5) was prepared and optimized by a Box-Behnken design. The higher temperature, molar ratio of urea to lanthanum and initial lanthanum concentration are beneficial for LC-ZSM-5 synthesis, and the adsorption capacity of LC-ZSM-5 under optimistic conditions was 91.2 mg-PO43-/g. The growth mechanism indicates that the LC particles grow larger with synthesis time and finally agglomerate, and 12 h is the best synthesis time. The thermodynamic results show that phosphate adsorption over LC-ZSM-5 is a spontaneously exothermic and combined physicochemical adsorption process. Kinetic studies suggest that higher temperatures help increase the phosphate adsorption rate, and chemical adsorption plays an important role during adsorption with an activation energy Ea of 42.7 kJ/mol. The adsorption mechanism of the phosphate uptake process includes electrostatic attraction and ligand exchange, through which LC is changed to lanthanum phosphate (LP) during adsorption. Finally, the regeneration study revealed that LC-ZSM-5 still exhibited a high adsorption capacity after 5 cycles, showing its satisfactory regeneration ability and potential industrial application.

Pupil detection is an indispensable step in eye-tracking, however, there are lots of difficulties in locating the pupil under low-resolution environments. This study proposes a self-training method of pupil detection for eye-tracking under low resolution. The system is applied to a typical application scenario as using a personal computer, a webcam with a resolution of $640 \times 480$ is used in our study. We first generate an initial pupil pattern by verifying the color intensity of the eye regions and estimate the gaze according to the matched pupil position in the further frames. After that, we utilize the computer users' actions of mouse clicks to calibrate the estimation result and annotate the position of the pupil to train the weight map of the pupil pattern. The experimental result shows that the proposed method could minimize the effect of bright spots, moreover, the precision of pupil detection and eye-tracking is increased. The proposed method will be potentially used in light-weight applications of human-computer interaction.

Fuel cell polymer membrane as the core of the proton exchange membrane fuel cell (PEMFC) plays an important role in maintaining high intrinsic proton conductivity and insulating electrode. To investigate the effect of crosslinking formation on proton conduction, the proton mobility and ion conduction were calculated and analyzed by using molecular dynamics (MD) simulation. As the crosslinking number increased, the proton diffusion coefficients increased at first and then decreased. The results indicated that the formation of crosslinked bonds was beneficial for opening new channels to enhance the proton conductivity. But too many crosslinking also can decrease proton diffusivity due to the blocking along the chain backbone. Besides, the proton conduction was better at 350 K than at 300 K. It can be concluded that temperature also had a significant impact on diffusivity and conductivity.

Eutrophication caused by excessive phosphate has become a global environmental issue that urgently needs to be solved due to its destructive effect on the ecosystem and adverse effect on human health. In this study, a novel lanthanum carbonate-grafted ZSM-5 zeolite (LC-ZSM-5) was developed to effectively achieve highly selective phosphate removal from wastewater. The LC-ZSM-5 adsorbent shows high adsorption capacity (highest at over 45 mg-PO43-/g) in the pH range of 3–6 with a fast adsorption rate (reaching 80% of the maximum adsorption capacity within 150 min and equilibrium at 350 min). High stability can be observed with less than 0.3 mg/L La leakage during the adsorption process. Four kinetic models are used to describe the adsorption process. The pseudo second order model and the Elovich model are found to fit the data best with a high correlation coefficient (r2 = 0.99), showing that the adsorption process is influenced simultaneously by the phosphate concentration and interaction between adsorbent and adsorbate. The change of curve slope from 4.0 to 0.89 and intercept from 0.76 to 27.6 in intra-particle model indicates that the adsorption process is controlled by a combination of intra-particle diffusion and film surface diffusion. The maximum phosphate adsorption capacity calculated from the Langmuir model is 47.7 mg-PO43-/g, and the adsorption isotherm data are fitted well by the Freundlich model (r2 = 0.95) and the Koble-Corrigan model (r2 = 0.95), suggesting that the phosphate adsorption process is dominated by nonregular multilayer adsorption with the coexistence of monolayer adsorption. The ionic strength and co-existing anions have little impact on the adsorption capacity of LC-ZSM-5, proving the adsorption selectivity of phosphate onto LC-ZSM-5. Characterization results show that spindle-like lanthanum carbonate particles are fabricated on ZSM-5. Combining the adsorption process and the characterization, it can be derived that phosphate is adsorbed by LC-ZSM-5 mainly through electric attraction and ligand exchange. Our study demonstrates the great potential application value of LC-ZSM-5 in commonly seen phosphate-containing wastewater.

FRP-concrete-steel tubular (FCS) composite columns are composed of the external tube, the internal steel tube, and the concrete between both tubes. They have been attracting the attention of many researchers due to their high ductility, lightweight, resistance to corrosion, and easiness of construction. However, there are few studies on FRP-concrete-steel tubular composite columns under eccentric load. To investigate the behavior of composite columns under the eccentric compression, a non-linear analysis program for FCS composite columns was compiled. The program was verified by existing tests, and the influences of eccentricity, FRP tube wall thickness, steel tube wall thickness, steel tube radius, slenderness ratio, and concrete strength grade on the eccentric compression performance were systematically analyzed. The results showed that the calculated results were in good agreement with the experimental results. It showed that the program can accurately reflect the deformation of FCS composite columns under various loads and estimate the ultimate load of FCS composite columns under eccentric compression. The eccentric ultimate load increased with the decrease of eccentricity and slenderness ratio, and with the increase of FRP tube wall thickness, steel tube wall thickness, and concrete strength grade. The ultimate eccentric load decreased with the increase of steel tube radius, but when the steel tube wall thickness reached a certain thickness, the ultimate eccentric load of FCS composite columns increases with the increase of steel tube radius. The conclusion can provide reference for the practical application of the structure.

Fuel cell polymer membranes such as the Dow, Nafion and Aciplex membranes as the core of the proton exchange membrane fuel cell (PEMFC) play an important role in maintaining high intrinsic proton conductivity. For investigating the dynamic properties and thermal properties of fuel cell polymer membranes, the proton mobility and thermal conductivities of the Dow, Nafion and Aciplex membranes were calculated by using molecular dynamics (MD) simulations. Compared with the Dow and the Nafion membranes, the Aciplex membrane presented a better mobility of water molecules and hydronium ions at 350 K and it showed a better thermal property due to its side chain is long enough to form a “highway” of heat conduction. The results indicated that both the structure of side chain and temperature have effect on the dynamic properties and thermal properties of fuel cell polymer membranes.