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Dendritic cell (DC) vaccines have shown promising effects in cancer management, while low cell activity and low migration rate to lymph nodes limit their clinical application. Here, this work reports a bioink DC vaccine, synthesized by 3D printing methacryloyl gelatin to encapsulate DCs and tumor cellular vesicles overexpressing programmed cell death protein 1 (PD1‐CVs), for cancer immunotherapy. Compared with a traditional hydrogel, the porous 3D scaffold significantly improves the viability of DCs from ∼16% to ∼70% after 7 days of cell culture and increases the proportion of released DCs from the scaffold into lymph nodes by about fourfold. The PD1‐CVs stimulate DC maturation and block PD ligand‐1 (PD‐L1) in mature DCs and tumor cells, synergistically boosting DC‐mediated antitumor immunity. In breast tumor mouse models, this personalized 3D DC vaccine developed for site‐specific filling after tumor resection significantly suppress tumor recurrence and extend median survival time to 45 days. This 3D printed vaccine offers a simple, safe, and robust strategy for enhanced cell‐based cancer immunotherapy. [ABSTRACT FROM AUTHOR]

The increasing popularity of proton exchange membrane electrolysis technology for hydrogen production has brought attention to the electrolytic water reaction. However, the slow kinetics of the oxygen evolution reaction (OER) at the anode have great influence on the overall efficiency of the reaction. While iridium oxide shows excellent stability under acidic conditions, its OER activity still needs to be improved. Here, we synthesized two‐dimensional amorphous iridium oxide (Am−IrO2) nanosheets with the thickness of only 6 nm by a mixed molten salt method. Such nanosheets show an ultralow overpotential of only 230 mV at 10 mA cm−2 in 0.5 M H2SO4. The overpotential increases only 40 mV after 90 hours of the stability test at this current density. Am−IrO2 can maintain the current density of ~400 mA cm−2 after 120 hours of test at 1.8 V in the PEM device, demonstrating good industrial prospects. Density functional theoretical calculations show that the oxygen vacancies, together with the upshift of the O 2p band center, are responsible for the improvement of OER in Am−IrO2. [ABSTRACT FROM AUTHOR]

The connection between the active components and supports in a catalyst is important for the high activity and long‐term stability during catalysis. Here, Co3O4 nanoparticles embedded in F, N‐doped graphene (Co3O4/F, N‐doped G) are synthesized by silicon‐hydrogen bond reduction. F and N atoms doped graphene interacts with Co3O4 nanoparticles to optimize oxygen reduction reaction (ORR) catalytic activity. The optimal Co3O4/F, N‐doped G‐2 catalyst with Co loading of 3.38 wt% shows a half‐wave potential of 0.852 V vs RHE in 0.1 M KOH solution. Furthermore, Co3O4/F, N‐doped G‐2 catalyst outputs an extremely high open circuit voltage of 1.47 V and an excellent power density of 280 mW cm−2 at current density of 450 mA cm−2 when applied to the primary Zn‐air batteries. Due to the synergetic effects from Co3O4 and supports (F, N‐doped G), Co3O4/F, N‐doped G‐2 catalyst also shows excellent stability and anti‐toxicity, and has good practical application prospects. [ABSTRACT FROM AUTHOR]

Electrochemical two‐electron oxygen reduction reaction (2 e− ORR) to produce hydrogen peroxide (H2O2) is a promising alternative to the energetically intensive anthraquinone process. However, there remain challenges in designing 2 e− ORR catalysts that meet the application criteria. Here, we successfully adopt a microwave‐assisted mechanochemical‐thermal approach to synthesize hexagonal phase SnO2 (h‐SnO2) nanoribbons with largely exposed edge structures. In 0.1 M Na2SO4 electrolyte, the h‐SnO2 catalysts achieve the excellent H2O2 selectivity of 99.99 %. Moreover, when employed as the catalyst in flow cell devices, they exhibit a high yield of 3885.26 mmol g−1 h−1. The enhanced catalytic performance is attributed to the special crystal structure and morphology, resulting in abundantly exposed edge active sites to convert O2 to H2O2, which is confirmed by density functional theory calculations. [ABSTRACT FROM AUTHOR]

Lattice strain plays a critical role in regulating the electronic structure and improving the performance of catalysts. Here, Ir−IrO2/C catalysts with different iridium content are obtained by annealing Ir/C in air. The growth of IrO2 on Ir nanoparticles can form a core–shell structure and introduces strain at their interface. The local compressive strain on Ir nanoparticles is 7.2 % in the optimal Ir−IrO2/C sample with Ir content of 14.3 % (Ir−IrO2/C‐3), which regulates the adsorption energy of intermediates and improves the catalytical performance of oxygen evolution reaction (OER). The overpotential of Ir−IrO2/C‐3 at 10 mA ⋅ cm−2 is 264 mV in acidic electrolyte, 35 mV lower than that of Ir−IrO2/C with no lattice strain. Ir−IrO2/C‐3 also exhibits the highest mass activity of 1304 A ⋅ gIr−1 at 1.55 V vs. RHE, which is higher than those of commercial catalysts. Furthermore, the activity of Ir−IrO2/C‐3 can maintain 42 h with the potential increase of only 18 mV at 10 mA ⋅ cm−2, proving that the lattice strain can also effectively improve the electrochemical stability. [ABSTRACT FROM AUTHOR]

Direct electrosynthesis of hydrogen peroxide (H2O2) via two‐electron pathway oxygen reduction reaction (2e− ORR) is crucially essential for a sustainable green economy. However, catalysts inevitably undergo four‐electron pathway oxygen reduction reaction (4e− ORR), resulting in low selectivity and economic benefits. The current challenge is to provide a feasible design strategy for obtaining satisfactory 2e− ORR catalysts with high selectivity. In this work, carbon dots (CDs) act as a cocatalyst to regulate the electron transport kinetics of In2O3/CDs, and the influence of CDs on the ORR pathways of In2O3/CDs is also studied. The electron transfer kinetics on In2O3/CDs composites are studied and analyzed using the transient photo‐induced voltage (TPV) technology. Combining the TPV results and kinetics analysis, it is shown that the electron transport on the In2O3 interface is obviously weakened after the addition of CDs, resulting in a high H2O2 selectivity. It is also demonstrated that CDs can effectively enhance the selectivity of H2O2, and the H2O2 selectivity of In2O3/CDs–10 is in close proximity to 100%, which is much higher than that of pure In2O3 (72%). This work will provide a new understanding and insight into addressing the challenge of low H2O2 selectivity for 2e− ORR catalysts. [ABSTRACT FROM AUTHOR]

Introduction: Idiopathic pulmonary fibrosis (IPF) is a serious lung disease with a high mortality rate. Baoyuan decoction (BYD), a classic medicinal food homology recipe, has anti‐apoptotic effects, enhances immune function, and alleviates fibrosis, suggesting that it may be a potential therapeutic drug for IPF. Objectives: We aimed to identify the main active ingredients of BYD, determine the basis of its efficacy, prove its anti‐IPF effects, and explore the mechanisms underlying its anti‐IPF effects. Materials and methods: In this study, the active components of BYD were detected and analysed by ultra‐high‐performance liquid chromatography coupled with hybrid quadrupole Orbitrap mass spectrometry (UHPLC‐Q‐Exactive Orbitrap‐MS). A network pharmacology analysis was performed to determine the potential targets and relevant pathways of BYD in treating IPF. Western blotting and quantitative real‐time polymerase chain reaction (qPCR) were conducted to verify the efficacy of BYD against IPF. Finally, molecular docking and qPCR were performed to identify the central targets of BYD. Results: A total of 39 components of BYD were identified. After performing the network pharmacology analysis, 35 active components and eight presumptive targets of BYD were found to play a central role in its anti‐IPF effects. The molecular docking results indicated that most of the active components of BYD exhibited good binding activity with these eight central target proteins. In addition, the expression of collagen, α‐SMA, and these eight targets in human pulmonary fibroblast (HPF) cells was suppressed from treatment with BYD. Conclusion: This study determined the efficacy of BYD against IPF and clarified its multiple‐target and multiple‐pathway mechanisms. Furthermore, the study also provides a new method for exploring the chemical and pharmacological bases of other traditional Chinese medicine (TCM). Baoyuan decoction (BYD) may be an effective drug for treating Idiopathic pulmonary fibrosis (IPF). We used UHPLC‐Q‐Exactive Orbitrap‐MS to identify the main ingredients of BYD and used network pharmacology and in vitro experiments to prove the anti‐IPF effect of BYD and explore the underlying mechanism by which it exerts this effect. The results showed that BYD treatment for IPF works through multiple components, targets, and pathways and that these pathways may produce better therapeutic effects through synergistic treatment. [ABSTRACT FROM AUTHOR]

Highly reactive polyols were prepared from modified acetic acid lignin (AAL) by a two‐step combination of mild hydrothermal degradation and hydroxylation. The AAL‐based polyols became relatively reactive and compatible with diisocyanate, with a reduction in the number average molecular weight (Mn) from 2923 to 684 g/mol and an increase in the hydroxyl content from 5.21 to 9.13 mmol/g. The mechanical performance and thermal properties of the AAL‐based polyurethane elastomers (LPUEs) strongly depended on the molecular weight and hydroxyl content of the AAL‐based polyols in the partial substitution of polytetramethylethylene ether glycol (PTMEG). This study proposed the prospective utilization of AAL as an alternative resource in the synthesis of polymers and biomaterials. © 2021 Society of Industrial Chemistry and John Wiley & Sons Ltd. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Ethanol is considered a better fuel than methanol in direct alcohol fuel cells because of the high energy density and low toxicity. Compared with noble metal catalysts, nickel‐based catalysts are much cheaper in price. However, present nickel‐based catalysts still surfer from some disadvantages such as low activity and high overpotential. In this paper, we show a new and high efficient nickel‐ based catalyst for ethanol oxidation. A layer of anodized nickel passivation film (Ni‐APF) was formed on the surface of nickel sheet by anodic oxidation method with carbon dots (CDs) as co‐catalyst. At the current density of 110 mA·cm−2, the potential for Ni‐APF/CDs was only 0.541 V (vs. Ag/AgCl), which was 18.8% lower than that of Ni‐APF. Low overpotential could reduce electrode thermal loss and increase output energy. Ni‐APF/CDs showed 144.4 mA∙cm−2 peak current density at peak potential 0.662 V (vs. Ag/AgCl), which was 31% higher than that of Ni‐APF (110.3 mA∙cm−2). In this system, CDs mainly function in the increase of charge‐transfer capacity and the promotion oxidation of carbonaceous intermediates. [ABSTRACT FROM AUTHOR]

Target localisation is one of the key technologies and a performance metric in underwater acoustic sensor networks. A number of range‐free and range‐based localisation algorithms are proposed. Among them a range‐based localisation algorithm: weighted centroid localisation (WCL) is widely used due to the relatively simple implementation and better localisation. The accuracy of WCL, however, is reduced when the sensor nodes are farther from the centre or inappropriate nodes are selected to perform the localisation. This study proposes a novel and an efficient node optimisation algorithm based on received signal strength and weighted centroid. The proposed algorithm consists of three stages: (a) to estimate a rough region of the target node using bearing line and azimuth; (b) to calculate the optimal localisation region by the optimal localisation region function, and then (c) compare the overlap area of the rough region of the target node and the optimal localisation region to select the optimal localisation node. Simulation experiments show that the proposed optimal localisation region function can accurately represent the optimal localisation region of the geometrical figure, composed of different nodes. The study compares the performance of our proposed algorithm with the typical WCL algorithm, and clearly shows significant improvement in the localisation accuracy. [ABSTRACT FROM AUTHOR]

The rutile phase IrO2, as a promising catalyst for oxygen evolution reaction (OER), still falls short of satisfactory activity. Here, a novel 1D monoclinic phase iridium‐ruthenium oxide solid solution (m‐IrxRu1‐xO2) is reported. For m‐IrxRu1‐xO2 with different metal proportions, the optimal m‐Ir0.91Ru0.09O2‐δ catalyst exhibits excellent OER activity under acidic conditions with an overpotential of 180 mV at 10 mA cm−2. As an anode catalyst in a proton exchange membrane electrolyzer, m‐Ir0.91Ru0.09O2‐δ with a low catalyst loading (0.1 mg cm−2) can operate ≈256 h at 1.8 V with a high current density over 900 mA cm−2 at room temperature. Such a satisfied stability may have originated from the specific morphology and crystal structure, which is confirmed by the transient potential scanning test. Density functional theory calculations show that the Ru in the m‐IrxRu1‐xO2 facilitates decreasing the OER overpotentials due to the electron transfer from Ru to Ir. [ABSTRACT FROM AUTHOR]

ABSTRACT Novel carboxyl- and amino-functionalized copolyesters, based on poly(ε-caprolactone)- block-poly(butylene fumarate)- block-poly(ε-caprolactone), were efficiently synthesized via Michael-type thiol-ene click chemistry. The resulting amphiphilic copolyesters with controllable molecular weights and abundant positively or negatively charged groups could spontaneously form pH-sensitive micelles in aqueous solutions, as confirmed by transmission electron microscopy, dynamic light scattering, fluorescence probing technique, and zeta potential analyses. Importantly, charge-reversal hybrid micelles can be obtained by co-assembly of carboxyl- and amino-functionalized copolyesters. The surface charges of hybrid micelles reversed rapidly from negative to positive at isoelectric point via protonation of surface carboxyl and amino groups. Interestingly, the hybrid micelles showed apparent pH-triggered Nile red-release behavior in acidic condition resembling tumor intracellular environment, which is fairly desirable for drug delivery. Our work indicates that co-assembly is a facile but efficient way to prepare charge-reversal micelles, which have great potential to be used as intelligent drug delivery systems for cancer therapy. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 1259-1267 [ABSTRACT FROM AUTHOR]

ABSTRACT A series of aliphatic-aromatic poly(carbonate- co-ester)s poly(butylene carbonate- co-terephthalate)s (PBCTs), with weight-average molecular weight of 113,000 to 146,000 g/mol, were synthesized from dimethyl carbonate, dimethyl terephthalate, and 1,4-butanediol via a two-step polycondensation process using tetrabutyl titanate as the catalyst. The PBCTs, being statistically random copolymers, show a single Tg over the entire composition range. The thermal stability of PBCTs strongly depends on the molar composition. Melting temperatures vary from 113 to 213°C for copolymers with butylene terephthalate (BT) unit content higher than 40 mol %. The copolymers have a eutectic melting point when about 10 mol % BT units are included. Crystal lattice structure shifts from the poly(butylene carbonate) to the poly(butylene terephthalate) type crystal phase with increasing BT unit content. DSC and WAXD results indicate that the PBCT copolymers show isodimorphic cocrystallization. The tensile modulus and strength decrease first and then increase according to copolymer composition. The enzymatic degradation of the PBCT copolymers was also studied. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41952. [ABSTRACT FROM AUTHOR]

A series of novel biodegradable poly(ester-carbonate) consisting of poly( L-lactic acid) (PLLA) and poly(butylene carbonate) (PBC) (PLLA- b-PBC) have been successfully synthesized by chain-extension reaction of dihydroxyl-terminated poly( L-lactic acid) prepolymer (PLLA-OH) and dihydroxyl-terminated poly(butylene carbonate) prepolymer (PBC-OH) using hexamethylene diisocyanate as a chain-extender. The chemical structures and molecular weights of copolymers are characterized by 1H NMR and gel permeation chromatography. The thermal properties, morphology, and mechanical properties of PLLA- b-PBC are investigated by differential scanning calorimetry, thermogravimetric analysis, phase contrast optical microscopy, and mechanical testing. The results indicate that PBC soft segment slightly increases the thermal stabilities and effectively enhances the impact strength of the copolymers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39158. [ABSTRACT FROM AUTHOR]

Poly(isosorbide carbonate) (PIC) was synthesized by melt polycondensation of dimethyl carbonate (DMC) and isosorbide using lithium acetylacetonate (LiAcac) as the catalyst. The reaction conditions were optimized to achieve PIC with relatively high number-average molecular weight ( Mn) of 28,800 g/mol and isosorbide conversion of 95.2%. A series of poly(aliphatic diol- co-isosorbide carbonate)s (PAICs) were also synthesized by melt polycondensation of DMC with isosorbide and equimolar amounts of aliphatic diols (1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and 1,4-cyclohexane dimethanol) in the presence of LiAcac and the TiO2/SiO2-based catalyst (TSP-44). PAICs with Mn values ranging from 18,700 to 34,400 g/mol and polydispersities between 1.64 and 1.69 were obtained. The 13C NMR analysis revealed the random microstructure of PAICs. The differential scanning calorimetry results demonstrated that all the PAICs were amorphous with a unique Tg ranging from 46 to 88 °C. The dynamic analysis results showed that the incorporation of linear or cyclohexane structure changed the dynamic mechanical properties of PIC drastically. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013 [ABSTRACT FROM AUTHOR]

Crosslinking is an effective way to improve polymer properties. This paper focuses on ultraviolet-induced crosslinking of poly(butylene succinate) (PBS) in the presence of a photoinitiator and a crosslinking agent at ambient temperature. The effects of the concentration of photoinitiator, the crosslinking agent content, and the irradiation time on the crosslink behavior were investigated. To obtain an appropriate gel fraction in different irradiation times, 3.0 wt% of photoinitiator and 10.0 wt% of crosslinking agent were proved to be the optimum choice. Furthermore, properties such as thermal properties, dynamic mechanical property, and enzymatic degradation of PBS before and after crosslinking were examined. Differential scanning calorimetry (DSC) analysis revealed that glass transition temperature ( T) increased with increase in gel fraction, while melting temperature ( T) and the degree of crystallinity decreased. This may be caused by the reduced molecular chain mobility and inhibited molecular motion for crystallization in crosslinked samples. The crosslinked polymer also showed improved thermal stability and dynamic mechanical property. In addition, the introduction of crosslinking retarded the enzymatic degradation rate of PBS, but it was still biodegradable. The improved properties of crosslinked PBS will extend the application of PBS. Copyright © 2009 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Summary: Aiming at further improving the energy efficiency of system while meeting the data rate requirement of the users, in this paper, a network energy efficiency optimization problem by jointly optimizing the resource allocation of macrocells and small cells is formulated and proven to be an NP‐hard problem, which cannot be worked out by direct methods in polynomial time. Considering the effectiveness of the modified particle swarm optimization (MPSO) algorithm, an MPSO‐based resource allocation and cell association algorithm is employed to solve the proposed joint optimization problem where the frequency resource partitioning of the macrocells, the transmission power, and the cell‐association bias of the small cells are jointly optimized. During the implementation of the optimization algorithm, the cell association alters with the transmission power and cell‐association bias adjustment, and the small cells where there are no active users associating with them will be turned off. The data rate requirement of the users is an indispensable metric in the communication system. Taking no account of the data rate requirement of the users, the frequency resource partitioning and cell association alteration will deteriorate the data rate of a few of users. Under such circumstances, we take the users' data rate requirement as a constraint of the joint optimization problem. The system level simulation results show that, by jointly optimizing the resource allocation of macrocells and small cells while guaranteeing the users' data rate requirement, the energy efficiency and system throughput can be further improved, and energy consumption can be further reduced. [ABSTRACT FROM AUTHOR]

Main observation and conclusion: Ethanol is considered a better fuel than methanol in direct alcohol fuel cells because of the high energy density and low toxicity. Compared with noble metal catalysts, nickel‐based catalysts are much cheaper in price. However, present nickel‐based catalysts still surfer from some disadvantages such as low activity and high overpotential. In this paper, we show a new and high efficient nickel‐ based catalyst for ethanol oxidation. A layer of anodized nickel passivation film (Ni‐APF) was formed on the surface of nickel sheet by anodic oxidation method with carbon dots (CDs) as co‐catalyst. At the current density of 110 mA·cm−2, the potential for Ni‐APF/CDs was only 0.541 V (vs. Ag/AgCl), which was 18.8% lower than that of Ni‐APF. Low overpotential could reduce electrode thermal loss and increase output energy. Ni‐APF/CDs showed 144.4 mA∙cm−2 peak current density at peak potential 0.662 V (vs. Ag/AgCl), which was 31% higher than that of Ni‐APF (110.3 mA∙cm−2). In this system, CDs mainly function in the increase of charge‐transfer capacity and the promotion oxidation of carbonaceous intermediates. [ABSTRACT FROM AUTHOR]

A new p- tert-butyl­thia­calix­[4]­arene derivative, C72H68N4O4S4·2CH2Cl2, has been synthesized and is comprised of one tetra- p- tert-butyltetrakis(2-cyano­benzyl­oxy)­tetra­thia­calix­[4]arene and two di­chloro­methane mol­ecules. The calix­[4]­arene mol­ecule is centrosymmetric and adopts an unusual 1,2-alternate conformation viaπ-π interactions between adjacent cyano­phenyl rings on the lower rim of the parent thia­calix­[4]­arene system. [ABSTRACT FROM AUTHOR]

A new p-tert-butylthiacalix[4]arene derivative, C(72)H(68)N(4)O(4)S(4) x 2CH(2)Cl(2), has been synthesized and is comprised of one tetra-p-tert-butyltetrakis(2-cyanobenzyloxy)tetrathiacalix[4]arene and two dichloromethane molecules. The calix[4]arene molecule is centrosymmetric and adopts an unusual 1,2-alternate conformation via pi-pi interactions between adjacent cyanophenyl rings on the lower rim of the parent thiacalix[4]arene system.