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Recent studies report that stem cell therapies have been applied successfully to patients, This has increased anticipations that this regeneration strategy could be a potential method to treat a wide range of intractable diseases some day. Stem cells offer new prospects for the treatment of incurable diseases and for tissue regeneration and repairation because of their unique biological properties. Angiogenesis a key process in tissue regeneration and repairation. Vascularization of organs is one of the main challenges hindering the clinical application of engineered tissues. Efficient production of engineered vascular grafts and vascularized organs is of critical importance for regenerative medicine. In this review, we focus on the types of stem cells that are widely used in tissue engineering and regeneration, as well as their application of these stem cells in the construction of tissue-engineered vascular grafts and vascularization of tissue-engineered organs.

We consider a fast-fashion brand that cooperates with a luxury brand, jointly launching a co-branded product. The impacts of the co-branding on the two brands’ original product lines are uncertain, and each brand can be either risk averse or risk neutral. Consumers, driven by exclusivity or conformity, are classified as either snobs or conformists. The equilibrium retail price, quality investment, and investment support are derived. The optimal market-targeting strategy for the fast-fashion brand as marketer of the co-branded product, is identified. We show that the fast-fashion brand is willing to give up either the conformist or the snob market under certain conditions, even when it has sales in both markets. In addition, given a particular market-targeting strategy, the fast-fashion brand benefits from its own risk aversion if the cost of risk is low, but the luxury brand is always worse off; the luxury brand may benefit from the fast-fashion brand’s risk aversion, however, if the market-targeting strategy is changed. Both brands are worse off when the luxury brand is risk averse.

A novel and high-efficiency Pd/TMxOy-rGO/CFP (TMxOy = Co3O4, Mn3O4, Ni(OH)2) electrocatalyst for directly integrated membrane electrode was synthesized by controllable cyclic voltammetry electrodeposition combined with hydrothermal process. The results showed excellent performance towards methanol oxidation reduction. The Pd/Co3O4-rGO/CFP as-prepared catalyst has the best electrocatalytic activity, and mass activity is 5181 mA·mg−1Pd, which is about 40 times and 4.3 times that of the commercial Pd/C and Pt/C catalyst (JM). It can be attributed that the small size of Pd nanoparticle, uniformity of distribution, and the synergistic interaction between transition metal oxide on the support surface and Pd nanoparticles. The prepared Pd/TMxOy-rGO/CFP composite electrode is a promising catalyst for integrated membrane electrode assembly of proton exchange membrane fuel cells in the future.

Direct ethanol fuel cell (DEFC) as a promising device for converting chemical energy to electricity has been paid ever-increasing attention. However, the slow kinetics of ethanol electrooxidation at an anode hinders the application of DEFCs. Although Pt is the best catalyst among all the pure metal catalysts, it still has a relatively poor ability to break the C C bond, is deactivated by the accumulated COad intermediates, and undergoes unwanted desired structure change over long-term operation. In recent years, the addition of other metals to form binary, ternary, and quaternary catalysts have significantly improved electroactivity and stability. Ternary catalysts can have numerous element combinations and complicated architectures and, therefore, have been the subject of considerable research. In this review, most of the reported ternary catalysts will be summarized and categorized according to their structure while discussing the essence of the role of each component.

This paper reports that the optical properties of anthraquinone (AQ) and its photo-catalytic performance in the visible light-driven p-xylene (PX) oxidation can be fine-tuned and improved through varying its skeleton substituents at the molecular level, and the electron-withdrawing substituent exhibits a better improvement effect than the electron-donating one. The best catalyst 2-carboxyanthraquinone (AQ-COOH) can achieve 70.9% PX conversion and 88.2% p-toluic acid selectivity under visible light illumination and 1 atm O2 pressure. The addition of benzenesulfonic acid in the above photocatalytic system can further increase PX conversion to 86.7%, along with a significant improvement in the selectivity of p-carboxybenzaldehyde and terephthalic acid, which likely originates from the unique recombination behavior of the photo-generated charge carriers of the catalyst and the additive driven by the strong interactions between their aromatic skeletons and acidic substituents. Furthermore, AQ-COOH can achieve almost quantitative yield of acetylacetone in ethylbenzene photooxidation and the regulating effect of toluene's para-position substituents on its reactivity is also reported in the AQ-COOH photocatalysis system. Based on quenching tests and EPR spectral characterizations, the oxygen vacancies (h+), superoxide free radicals (O2•-) and singlet oxygen (1O2) as the photo-generated active species are involved in the proposed photo-catalysis mechanism.

Controllable fabrication of Fe-N-C based single-atom catalysts (SACs) for enhanced electrocatalytic performance is highly desirable but still challenging. Here, an in situ surface-confined strategy was demonstrated for the synthesis of single atomic Fe-N4 on N-doped carbon nanoleaves (L-FeNC). The in situ generated Zn3[Fe(CN)6]2 could not only serve as a protection layer against collapse of nanoleaves but also provide abundant Fe source for the formation of Fe-N moieties during pyrolysis, leading to high surface area and high graphitization degree of L-FeNC simultaneously. Benefiting from abundant Fe-N4 active sites, enhanced mass and charge transfer, the as-prepared L-FeNC manifested a half-wave potential of 0.89 V for oxygen reduction reaction (ORR) in 0.1 M KOH. A maximum power density of 140 mW cm−2 and stable discharge voltage even after operation for 50,000 s have been demonstrated when the L-FeNC was used as air cathode for Zn-air battery. This work not only provided a unique surface-confined strategy for the synthesis of two-dimensional nanocarbons, but also demonstrated the significant benefit from rational design and engineering of Fe-N-C SACs, thus offering great opportunities for fabrication of efficient energy conversion and storage devices.

The strong metal–support interaction (SMSI) between metals and reducible supports (e.g., CeO2, TiO2, and SnO2), which has been widely investigated, plays a very important role in heterogeneous catalysis. We report the first example of SMSI between palladium (Pd) and gallium oxide (Ga2O3) within a PdGa nanoparticle (denoted as PdxGay NP, where x:y is the atomic ratio of Pd and Ga). The typical features of classic SMSI, such as electron transfer between Ga2O3 and Pd and suppression of H2 and CO adsorption, are successfully observed on PdxGay NPs. Detailed characterizations and control experiments demonstrate that the coexistence of PdGa alloy and Ga2O3 in PdxGay NPs plays a vital role in the formation of SMSI. To systematically study the effects of SMSI on catalytic performance, PdxGay NPs were used as “self-supported catalysts” for propyne semi-hydrogenation (PSH), a critical process for removing trace propyne from propylene in industry. It is shown that optimized Pd0.34Ga1 NPs give a propylene selectivity of 98.2% at a propyne conversion of 96.6% at 30 °C and atmospheric pressure, which is much higher than that of pure Pd NPs and Pd/Ga2O3 catalysts prepared by a conventional wet-impregnation method. The reaction paths of PSH on PdxGay NPs have been further revealed by density functional theory (DFT) calculations. This work may not only deepen the basic understanding of SMSI, but also promote the design and application of heterogeneous catalysts.

Hydrogen is the core source to both refinery and synthetic plant of chemicals. Refinery consumes high purity hydrogen while synthetic plant of chemicals needs syngas consists of hydrogen and carbon oxides. As main hydrogen production technologies, industrial coal gasification and steam methane reforming based pathways generate H2, CO and CO2, which is actually the mixture of hydrogen and carbon oxides. Hence, the gases demand of refinery and synthetic plant of chemicals and their supply from hydrogen production can form hybrid hydrogen networks. On the basis of complementary reuse, this paper firstly proposes integration of hybrid hydrogen network for refinery and synthetic plant of chemicals. Superstructures of individual and hybrid hydrogen networks are employed as problem illustration and corresponding linear programming (LP) mathematical models are formulated. Practical refinery and synthetic plant of chemicals cases are employed to demonstrate its application. Compared with individual networks, the natural gas conservation case can recover 8660.4 Nm3·h-1 hydrogen in purge gas, reduce 1386.6 Nm3·h-1 CO2 emission, equaling to reduction of 278.11 kmol·h-1 natural gas feedstock and 14.8% of total gas production load; the coal conservation case can even waive the total coal consumption and extra 104.1 kmol·h-1 natural gas, recover 8660.4 Nm3·h-1 hydrogen in purge gas, reduce 5255.8 Nm3·h-1 of CO2 emission and decrease 21.2% of the total gas production load. Furthermore, economic evaluation is also placed to account for the economic advantage of hybrid network.

Due to the multi-functional requirements, more and more multi-dimensional functionally graded structures are reported, while their thermo-mechanical performances are still unclear. This paper aims at theoretically examining the thermo-mechanical behaviors of two-dimensional functionally graded (2D-FG) microbeam excited by a moving load. The formulation is established in the framework of the modified couple stress theory in combination with Hamilton's principle, and this problem is numerically solved through the finite element method (FEM). The material properties of the 2D-FG microbeam are treated as temperature-dependent parameters that vary smoothly along with both the axial and thickness directions, and three different thermal loads including the uniform, linear, and nonlinear temperature rises are taken into account. Both the fundamental frequency and the dynamic transverse deflection are analyzed with consideration of different axial and thickness gradient indexes, thermal load types, temperature rise amplitudes, and small scale parameters. The conclusion obtained in this paper can serve as a guideline for assessing the thermal performance of microstructures subjected to a moving load.

Platelet-neutrophil crosstalk is being increasingly recognized as a driver of inflammation and thrombosis in patients with ischemic stroke. The aim of this study was to investigate the potential of PNR value in predicting the long-term prognosis and evaluate whether or not an available and routine blood cell biomarker could help predict the long-term neurological function and mortality in AIS patients.A total of 718 patients with suspected acute ischemic stroke were involved and followed up for 1 year by standard telephone interview or reexamination. Kaplan-Meier curve, Univariate and Multivariate Cox Regression were analyzed using Statistical Packages for Social Sciences.ROC curve for PNR to evaluate 1-year outcomes was analyzed and the area under the curve (AUC) was 0.659 (P0.001). The cutoff point was observed at 38.30, with a sensitivity of 53.09% and a specificity of 71.25%. Moreover, patients in PNR≤38.30 were more likely to have more serious NIHSS on admission, 1-year mRS and higher 1-year mortality (P0.001, respectively). The 1-year mortality in the low PNR group was significantly higher than that of the high PNR group (log-rank tests: P0.0001). Age, NIHSS, RBC and PNR were combined into model B which significantly increased the AUC value from 0.736 to 0.888 compared to model A (including Age, NIHSS and RBC).PNR may serve as a readily assessable biomarker for early predicting neurological deterioration and the long-term prognosis of AIS. The nomogram that included age, NIHSS, PNR and RBC may be a useful predictive tool for 1-year mortality.

The Ski-interacting protein (SNW1) acts as a transcriptional co-regulator associated with mRNA splicing and transcription, cell cycle progression, acute and chronic inflammatory responses, however, its role involved in host antiviral innate immune responses remains to be explored. Here, for the first time, we demonstrated that SNW1 positively regulates the expression of pro-inflammatory cytokines and interferon (IFN) responses induced by influenza A virus (IAV) infection, and further inhibits virus replication by performing SNW1 depletion or overexpression approaches. Furthermore, we showed that reduced interferon beta (IFN-β) expression caused by interfering SNW1 impairs the activation of JAK-STAT pathway in response to IAV or poly I:C. Importantly, by interacting with IKKγ, the regulatory subunit of IκB kinase (IKK) complex, SNW1 promotes IAV-induced activation of NF-κB and phosphorylation of TBK1 kinase, leading to the increase of antiviral effectors interleukin 6 (IL-6), C-X-C motif chemokine 10 (CXCL10), IFN-β and myxovirus resistance protein 1 (MX1). Taken together, our study revealed that SNW1 is an important mediator of host defenses against IAV through the induction of pro-inflammatory factors and IFN signaling, providing novel insights in modulating innate immune responses to protect host from IAV infection.

Zealandia was once located at the active Gondwana margin and experienced complicated tectonic evolution from continental breakup to subduction and oblique slipping along the plate boundary. Here, we investigate the lithospheric thermal and rheological properties via spatial variations in effective elastic thickness (Te). Using the topography, sediment thickness and gravity data, the fan wavelet coherence method is employed to recover Te values. The effects of dynamic topography and gravity in the subduction zone on the estimated Te are considered and removed. The final results reveal that the Te variation pattern generally coincides well with the tectonic regimes. Relatively high Te values up to 22 km are observed in North Island and the southernmost part of South Island, while central and northern South Island are dominated by smaller Te values (~15 km) similar to those of the surrounding submerged plateaus. We interpret the relatively high Te values as indicating the combined lithospheric strength due to the contacting plates in the subduction zone. To the north along the Tonga-Kermadec subduction zone, the lithosphere surprisingly exhibits anomalously high Te values, ranging from 22 to 36 km, which contradicts the geological evidence of normal faults developed in the incoming Pacific Plate and the magmatism in the overlying Australian Plate that generally contribute to low lithospheric strength. We speculate that the high-Te zone is related to the large bathymetry and gravity anomalies in the bending plate and controlled by non-isostatic factors. Finally, we find widespread low Te values covering the entire arcs and oceanic basins in northern Zealandia, which may indicate that regional lithospheric thinning associated with delamination weakened the integrated strength of the lithosphere.

Molecularly imprinting polymers (MIPs), as artificial antibodies with high recognition selectivity to template molecules, are widely used in various biosensors. To improve further the selectivity of MIPs-based photoelectrochemical (PEC) biosensors, we report a differential strategy using non-imprinted polymers (NIPs) as the reference. In a proof-to-concept example for the determination of dopamine (DA), MIPs and NIPs membranes were fabricated by electrochemical polymerization of polypyrrole membranes on the surface of graphene quantum dots (GQDs)/TiO2 nanotubes (NTs). The photocurrent difference between the two PEC cells, MIPs@GQDs/TiO2 NTs−Pt and NIPs@GQDs/TiO2 NTs−Pt, was measured as the signal. As the non-specific adsorption of non-template molecules on the outside surface of MIPs and NIPs membranes is similar, the anti-interference ability for the determination of DA is much improved by using differential strategy. In the normal and differential PEC measurement models, 10.0 μM ascorbic acid is equivalent to 3.12 and 0.40 μM DA, respectively. Further, the smaller specific surface area in NIPs membrane was compensated by using a weight factor to correct the residual interference in a modified differential model. By using 10.0 μM ascorbic acid as the balance point, the presence of 10.0 μM H2O2, glutathione, uric acid or glucose is equivalent only to 0.090, 0.061,0.11 or 0.041 μM of DA, respectively, which are about 3–7% of their interference levels in the normal photocurrent model. The differential PEC method was applied in the determination of DA in serum samples in the linear range of 0.05–12.5 μM, with the detection limit of 0.018 μM.