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Hypoxia-induced angiogenesis plays a critical role in wound healing, which could be disturbed by multifactors. Upon hypoxia stimulation, CXCL12 and its receptor CXCR4 were significantly upregulated in human umbilical vascular endothelial cells (HUVECs); thus, we attempted to investigate the role and mechanism of CXCL12 in HUVEC angiogenesis under hypoxia. Via downloading and analyzing microarray profiles (GSE76743 and GSE116909), we found that LINC01693 was positively correlated with CXCL12 and upregulated by hypoxia in HUVECs, while miR-302d was downregulated by hypoxia and might target LINC01693 and CXCL12. RELA, a critical transcriptional factor for response to hypoxia, could bind to LINC01693 promoter to activate its transcription, therefore, promoting CXCL12 expression under hypoxia. LINC01693 served as a competing endogenous RNA for miR-302d to counteract miR-302d-mediated CXCL12 suppression via direct targeting. Hypoxia-induced CXCL12 upregulation and angiogenesis in HUVECs could be significantly suppressed by LINC01693 silence while enhanced by miR-302d inhibition; the effect of LINC01693 silence could be partially reversed by miR-302d inhibition. Taken together, RELA promotes the angiogenesis in HUVECs via LINC01693/miR-302d/CXCL12 axis. We provide a novel mechanism and experimental basis of CXCL12 function in hypoxia-induced HUVEC angiogenesis.

Exploration of simple and economical synthetic routes to construct active two‐photon initiators (2PIs) with long conjugation length is highly desirable to promote the development of two‐photon‐induced photopolymerization technology. In this article, several conjugated carbazole‐based derivatives containing N=C bonds as π bridges and electron donor/acceptor groups were prepared through one‐step Schiff base reaction. The structure–activity relationship was systematically investigated through calculations and experimental tests. The results showed that compared to the D‐π‐D‐π‐D molecules, the A‐π‐D‐π‐A molecules exhibited stronger charge transfer, which induce redshifted linear absorption and enhanced two‐photon absorption at 800 nm. The 2PIs displayed aggregation‐induced emission property and show potential for the fabrication of luminescent microdevices. In two‐photon‐induced microfabrication tests, the formulations containing novel 2PIs exhibited lower threshold energy than the widely used commercial photoinitiator Irgacure 369 and the two‐photon resists IP‐L is the brand name of the two‐photon resist from Nanoscribe, specially designed for nanoscribe's laser lithography systems. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2692–2700

MoSe2 has the genuine potential as anode material for lithium-ion batteries, benefiting from its layered structure, large interlayer space and high specific capacity. In this work, we achieve the controllable and in-situ synthesis of MoSe2-C nanocomposites and investigating the dimensional effects (grain size, interlayer distance, and slabs of stacking in number) of carbon content on the MoSe2-C hybrid material. The optimized anode MoSe2-15.0%C delivers prominent cycling performance (a high reversible capacity of 1165 mAh g−1 after 150 cycles at 0.2 A g−1 and 860 mAh g−1 after 150 cycles at 1 A g−1) and compelling rate behavior (734 mAh g−1 even at a current density of as high as 10 A g−1). The above elucidates that the modest carbon layer not only guarantee the integrity of the electrode by avoiding the structure collapse, but also elevate the electric conductivity to supply quick discharging and charging. The outstanding electrochemical performance is attributed to the synergistic effect between MoSe2 and the carbon. Hence, MoSe2-C nanocomposites could be deemed as promising anode materials in lithium-ion batteries.

Concrete filled steel tubular column comprising a hollow steel tube infilled with concrete has been used widely in high rise buildings. Although modern design codes provide guides on concrete filled steel tubular members, they do not cover their applications involving high strength concrete and high tensile steel. Set against this background, new tests have been conducted to supplement the dearth of research on concrete filled steel tubular members with ultra-high strength concrete (fck up to 190N/mm2) and high tensile steel (fy up to 780N/mm2). In this paper, a design guide has been proposed for concrete filled steel tubular members based on an extension of Eurocode 4 method for concrete compressive strength up to 190N/mm2 and high tensile steel with yield strength up to 550N/mm2. More than 2030 test data collected from the literature on concrete filled steel tubes with normal and high strength materials have been analysed to formulate this design guide. This paper provides insights to this design guide sharing some of the expertise and knowledge involving the applications of high strength concrete filled tubular members in high rise buildings.

This study is motivated by increasingly prevalent use of High Tensile-Strength steel (HTS) in constructions, where fire is one of the extreme conditions that need to be taken into account in design phase. Previous studies showed lack of awareness regarding the effects of heat-treatment methods on temperature dependent mechanical properties of the HTS. With this research gap being identified, standard tensile tests for Grade S690 steels made from Quench-Temper (QT) Process and Thermo-Mechanically Controlled Process (TMCP) were conducted. Transient-state were adopted. The mechanical properties were compared and their differences were discussed. In General, the elastic moduli were similar for HTSs from different heat-treatment methods, but the effective yield strength of TMCP-S690 deteriorated more than that of QT-S690 at elevated temperatures.

The multidrug resistance (MDR) of cancer cells is a major obstacle in cancer chemotherapy and very few strategies are available to overcome it. Here, a new strategy is developed to codeliver a π–π stacked dual anticancer drug combination with an actively targeted, pH- and reduction-sensitive polymer micellar platform for combating multidrug resistance and tumor metastasis. In contrast to other methods, two traditional chemotherapeutics, doxorubicin (DOX) and 10-hydroxycamptothecin with complex aromatic π–π conjugated structures, are integrated into one drug delivery system via a π–π stacking interaction, which enables the released drugs to evade the recognition of drug pumps due to a slight change in the drug's molecular structure. The micelles exhibit active targeting of DOX-resistant human breast cancer MCF-7 cells (MCF-7/ADR) and have the ability to control the release of the drug in response to the microenvironmental stimuli of tumor cells. As a result, the codelivery of the π–π stacked dual anticancer drug combination displays high therapeutic efficacy in the MCF-7/ADR tumor model and successfully prevents the lung metastasis of tumor cells. The mechanism underlying the reversal of MDR is investigated, and the results reveal that the synergistic effect of the π–π stacked dual drugs promotes mitochondria-dependent apoptosis.

Lithium-ion batteries (LIBs) have been widely applied and studied as an effective energy supplement for a variety of electronic devices. Titanium dioxide (TiO2 ), with a high theoretical capacity (335 mAh g-1 ) and low volume expansion ratio upon lithiation, has been considered as one of the most promising anode materials for LIBs. However, the application of TiO2 is hindered by its low electrical conductivity and slow ionic diffusion rate. Herein, a 2D ultrathin mesoporous TiO2 /reduced graphene (rGO) heterostructure is fabricated via a layer-by-layer assembly process. The synergistic effect of ultrathin mesoporous TiO2 and the rGO nanosheets significantly enhances the ionic diffusion and electron conductivity of the composite. The introduced 2D mesoporous heterostructure delivers a significantly improved capacity of 350 mAh g-1 at a current density of 200 mA g-1 and excellent cycling stability, with a capacity of 245 mAh g-1 maintained over 1000 cycles at a high current density of 1 A g-1 . The in situ transmission electron microscopy analysis indicates that the volume of the as-prepared 2D heterostructures changes slightly upon the insertion and extraction of Li+ , thus contributing to the enhanced long-cycle performance.

Due to the earth abundance and tunable electronic properties, etc., transition metal oxides (TMOs) show attractive attention in oxygen evolution reaction. O-vacancies (Vo ) play important roles in tailoring the local surface and electronic environment to lower the activation barriers. Herein, an effective strategy is shown to enhance the oxygen evolution reduction (OER) performance on Co3 O4 ultrathin nanosheets via combined cation substitution and anion vacancies. The oxygen-deficient Fe-Co-O nanosheets (3-4 nm thickness) display an overpotential of 260 mV@10 mA cm-2 and a Tafel slope of 53 mV dec-1 , outperforming those of the benchmark RuO2 in 1.0 m KOH. Further calculations demonstrate that the combined introduction of Fe cation and Vo with appropriate location and content finely tune the intermediate absorption, consequently lowering the rate-limiting activation energy from 0.82 to as low as 0.15 eV. The feasibility is also proved by oxygen-deficient Ni-Co-O nanosheets. This work not only establishes a clear atomic-level correlation between cation substitution, anion vacancies, and OER performance, but also provides valuable insights for the rational design of highly efficient catalysts for OER.

A new type of absorber, a four-tined fish-spear-like resonator (FFR), constructed by the two-photon polymerization process, is reported. An absorbance of more than 90% is experimentally realized and the resonance occurs in the space between the tines. Since a continuous layer of metallic thin film covers the structure, it is perfectly thermo- and electroconductive, which is the mostly desired feature for many applications.

The Y(OTf) 3 -catalyzed aerobic oxidative cyclization reaction for the selective synthesis of dihydroquinazolinones and quinazolinones has been developed. This method provides a practical, effective and green synthetic approach to dihydroquinazolinones and quinazolinones which both are important units in many biologically active compounds.

Silicon carbide (SiC) coatings were produced on carbon/carbon (C/C) composites substrates using chemical vapor deposition (CVD) at different temperatures (1100°C, 1200°C, and 1300°C). The deposition rate was found to increase with deposition temperature from 1100°C to 1200°C. From 1200°C to 1300°C, the deposition rate decreased. SiC coating produced at 1200°C exhibited a strong (111) texture compared with the coatings produced at other temperatures. Both hardness and Young's modulus were also found to be higher in the coating produced at 1200°C. The variation in mechanical properties with the increase in temperature from 1100°C to 1300°C showed a direct correlation with the change in deposition rate and (111) texture. Microstructure analysis shows that the change in CVD temperature leads to the change in grain size, crystallinity, and density of stacking faults of SiC coatings, which appears to have no significant effect on mechanical properties of SiC compared with the texture observed in SiC coating. For the coating deposited at 1200°C, both the hardness and Young's modulus increased gradually from the substrate/coating interface to the top surface. The nonuniformity of mechanical properties along the cross-section of the coating is attributed to the nonuniform microstructure.

A novel zinc phthalocyanine containing four 17-crown-5 ether voids(17C5ZnPc) has been synthesized and characterized. UV-visible absorption and fluorescence emission spectra and as sociated photophysical parameters have been determined. In contrast to most of the crown ether substituted phthalocyanines, no cofacial dimer formation is observed in the presence of alkali metal salts. In addition to the fluorescence at 710 nm from S1, a strong upper excited state (Soret S2) emission around 424 nm has been detected for the first time in the phthalocyanine series. Fluorescence decay of S1 and S2 emission can be analyzed by mono- and biexponential fits respectively. X-ray structure analysis showed that the crown ether unit is conformationally deformed and oblate that may account for the unusual spectroscopic properties.

The enhancement of cellular internalization and subsequent achievement of a nuclear targeting of nanocarriers play an important role in maximizing the therapeutic potency and minimizing the side effects of encapsulated drugs. Herein, a multifunctional micellar nanoplatform simultaneously with high cell penetration and nuclear targeting through pH-triggered surface charge reversal is presented. The miscellar system is constructed from poly(ethylene glycol)-poly(ε-caprolactone) with 2,3-dimethylmaleic anhydride-Tat decoration (PECL/DA-Tat). DA groups are used to mask the positive charge of Tat to prolong blood circulation of the nanocarriers. In the mildly acidic environment of tumor tissue, the system exhibits ultrasensitive negative to positive charge reversal, facilitating the cell internalization and subsequent nuclear targeting. The chemotherapeutic 10-hydroxycamptothecin conjugated to methoxy polyethylene glycol, which is loaded in this micelle, obviously enhances cytotoxicity against tumor cells. The in vivo therapy in mice bearing 4T1 breast tumor reveals that the system has a significant enhancement of both the endocytosis and nuclear enrichment, showing a highly effective antitumor efficacy and inhibition to lung metastasis.

The YCl 3 -catalyzed aerobic oxidative cyclization reaction for the synthesis of benzothiazoles has been developed. This method provides a practical, effective and green synthetic approach to benzothiazoles which are important units in many biologically active compounds.

In this study, Yb immobilized NaY zeolite catalyst (Yb/NaY) was obtained by a hydrothermal method and characterized by XRD, BET, FT-IR, ICP-AES, and NH 3 -TPD. The catalyst displayed good catalytic activity when applied to the synthesis of quinoxalines via condensation of α-hydroxyketones with 1,2-diamines, and could be reused several times without any loss of catalytic activity.

Polydnavirus was purified from the calyx fluid of Cotesia plutellae ovary. The genomic features of C. plutellae polydnavirus (CpPDV) were investigated. The viral genome consists of at least 12 different segments and the aggregate genome size is a lower estimate of 80kbp. By partial digestion of CpPDV DNA with Bam HI and subsequent ligation with Bam HI-cut plasmid Bluescript, a representative library of CpPDV genome was obtained.

A robust and smart protoporphyrin-based polymer nanoplatform, which is capable of successively recognizing the variation of biological signals and reacting with them in a dynamic mode, is successfully developed. It combines the chemotherapy and photodynamic therapy in a same system, leading to a high treatment outcome while a low adverse side effect of therapeutic agent.

The solid-state photoreaction of the mixed crystals between nitrobenzaldehydes and indole was found to give nitrophenyl-(bis-3-indolyl)methane (3) and nitrophenyl-(3-indolyl)methanol (4). The structure of the ortho isomer 4c was established by X-ray crystallographic analysis. A dual pathway from an oxetane intermediate 5 is proposed for the formation of 3 and 4.