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Abstract: An efficient method for the synthesis of α-aminonitriles via one-pot three-component condensation of ketones, amines and potassium hexacyanoferrate(II) using benzoyl chloride as a promoter and PEG-400 as a reaction medium was described. This protocol has the features of use of eco-friendly cyanide source, green reaction medium, high yield, and simple work-up procedure. [Copyright &y& Elsevier]

Abstract: Leonard and Pellikaan developed the qth power algorithm to compute module bases for the integral closure of the polynomial ring in a class of function fields. In this paper, their algorithm is adapted to efficiently obtain an -basis for a class of Riemann–Roch spaces without having to compute the entire integral closure. This reformulation allows one to determine the complexity of the algorithm. Further, we obtain a simple characterization of the integral closure. [Copyright &y& Elsevier]

A unit cell-based design support system (UCBDSS) for composite structural design is introduced. A unit cell is defined as the smallest representative volumetric element to carry the information of composite constituent materials, heterogeneous structures, homogenized mechanical properties, and appropriate manufacturing processes. The database of various composite unit cells is organized to form a unit cell library (UCL). The UCBDSS can intelligently use the information from the UCL to simplify and automate the composite design process, to increase the design efficiency, and to facilitate the tailored composite structure design. The framework of the UCBDSS, its modules, the development of the UCL, the blackboard architecture for design control, and the UCBDSS working environment for Internet-based design are presented. [Copyright &y& Elsevier]

Development of effective methods for quantificationally characterizing the thermal resistance of the intumescent char layer of fired fire-retardant coating is of interest in many academic researches and industrial applications. In this work, a novel approach is proposed to calculate the thermal resistance of the intumescent char layer produced after the ultra-thin fire-retardant coating exposed to fire. A correlation was established based on the relative thermal resistance of the char layer to that of steel plate and the surface temperature at the back of the coated steel plate under steady-state heat transfer. The thermal resistance of the steel plate was obtained about 0.009 K·m2·W−1 by calculating the heat flux based on the radiation heat exchange involving three-surface enclosure model (flame, steel, and wall). The thermal resistances of the char layers without and with the layered double hydroxide (LDH) were 0.011 K·m2·W−1 and 0.013 K·m2·W−1, respectively. The results show that the external roughness and internal honeycomb structure can increase both the conductivity and the convective thermal resistances of the char layer to protect the steel structures. The porosity of the char layer is between 0.15 and 0.18, and its thermal conductivity is between 0.4 and 0.8 W·m−1·K−1 in the process of fire. Unlabelled Image • A novel method is proposed to calculate thermal resistance of intumescent char layer. • Thermal resistance is used to evaluate heat-shielding performance of char layer. • LDH improves external roughness and internal honeycomb structure of char layer. • Porosity of char layers is obtained to be 0.15–0.18 via SEM images processing. • Thermal conductivity of char layers is 0.4–0.8 W·m−1·K−1 in the process fire. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy and performance of traditional image threshold segmentation algorithm, this paper proposes a multithreshold segmentation method named improved Harris hawk optimization (IMHHO). Firstly, IMHHO adopts Tent map and elite opposition-based learning to initialize population and enhance the diversity. Secondly, IMHHO uses quadratic interpolation to generate new individuals and enhance the local search ability. Finally, IMHHO adopts improved Gaussian disturbance method to disturb optimal solution, which coordinates the local and global search ability. Then, the performance of IMHHO is tested based on 14 benchmark functions. In image segmentation, different algorithms are tested to compare the comprehensive performance based on Otsu and Renyi entropy. Experiments show that IMHHO performs better in the three kinds of benchmark functions; the segmentation effect is directly proportional to the number of thresholds; compared with other algorithms, IMHHO has better comprehensive performance. [ABSTRACT FROM AUTHOR]

Despite its great potential in cancer therapy, phototherapy, including photothermal therapy (PTT) and photodynamic therapy (PDT), often cause metastasis of tumors. Immunotherapy has revolutionized the cancer treatment owing to the capability of activating immune system to eliminate tumors. However, the integration of phototherapy and immunotherapy in a single nanoagent for cancer therapy is still a challenging task. Here, we fabricated (Cu9S5@mSiO2-PpIX@MnO2@CpG (CSPM@CpG)) as a synergistic therapeutic model for phototherapy enhanced immunotherapy. The intracellular uptake of cytosine-phosphate-guanine (CpG) promoted the infiltration of cytotoxic T lymphocytes (CTLs) in tumor tissue, further stimulating the production of interferon gamma (IFN-γ) and remarkably elevating the immune response level. Excellent anti-tumor effects have been achieved by synergistic PTT/PDT/immunotherapy. The metastasis of tumors was effectively inhibited by the immune response of CpG. Thus, our proposed work provides a strategy to combine phototherapy with immunotherapy to enhance the therapeutic efficiency and further inhibit metastasis of tumors. CpG oligonucleotides can stimulate an anticancer immune response. Zhou et al. now develop nanoparticles that can deliver CpG, which promotes cancer cell death after photothermal and photodynamic therapy in vitro and in vivo, concomitant with an immunological response. [ABSTRACT FROM AUTHOR]

• A smartphone-assisted fluorescence-colorimetric immunosensing platform was proposed. • NH 2 -UiO-66@PtNPs was exploited to construct a fluorescence-colorimetric signal probe. • The multi-mode immunosensing microarray showed satisfactory results of AMD detection. • The efficient, visual and portable method showed great potential in food analysis. Amantadine (AMD) is an antiviral drug used to treat animal-based infectious diseases such as avian influenza. However, its illegal use in animal-derived food industries endangers human health. Therefore, an efficient, portable, and visual sensor to detect AMD in food is crucial for ensuring food safety. A multifunctional nanocomposite NH 2 -UiO-66@PtNPs was exploited to design a smartphone-assisted fluorescence-colorimetric immunosensing microarray for multidimensional detection of AMD in animal-derived foods. Platinum nanoparticles (NPs) were immobilized on a Zr-based metal–organic framework (NH 2 -UiO-66). Pt NPs exhibited peroxidase-like activity, whereas NH 2 -UiO-66 stabilized Pt NPs and improved the colorimetric signal of the sensor. Moreover, the fluorescence ligand NH 2 -BDC in NH 2 -UiO-66 was released via alkaline hydrolysis, amplifying the fluorescence signal and improving detection sensitivity. The smartphone-assisted color recognition system accurately identified the color changes of the microarray. The immunocompetitive reaction of AMD and the antibody (Ab) in the microarray NH 2 -UiO-66@PtNPs@Ab 2 allowed the quantitative and visual detection of AMD in a wide concentration range (0.1–1000 ng/mL) with high sensitivity [limit of detection = 0.0022 ng/mL (fluorescence), 0.069 ng/mL (colorimetric), and 0.68 ng/mL (smartphone)]. This detection strategy was verified in AMD-spiked food samples with satisfactory recoveries (82.0–103.0%) and stability (RSD: ≤7.1%, n = 3), showing its great potential for visual screening and portable detection of other food contaminants. [ABSTRACT FROM AUTHOR]

Summary: Rice blast and bacterial blight represent two of major diseases having devastating impact on the yield of rice in most rice‐growing countries. Developments of resistant cultivars are the most economic and effective strategy to control these diseases. Here, we used CRISPR/Cas9‐mediated gene editing to rapidly install mutations in three known broad‐spectrum blast‐resistant genes, Bsr‐d1, Pi21 and ERF922, in an indica thermosensitive genic male sterile (TGMS) rice line Longke638S (LK638S). We obtained transgene‐free homozygous single or triple mutants in T1 generations. While all single and triple mutants showed increased resistance to rice blast compared with wild type, the erf922 mutants displayed the strongest blast resistance similar with triple mutants. Surprisingly, we found that Pi21 or ERF922 single mutants conferred enhanced resistance to most of tested bacterial blight. Both resistances in mutants were attribute to the up‐regulation of SA‐ and JA‐pathway associated genes. Moreover, phenotypic analysis of these single mutants in paddy fields revealed that there were no trade‐offs between resistances and main agricultural traits. Together, our study provides a rapid and effective way to generate rice varieties with resistance to both rice blast and bacterial blight. [ABSTRACT FROM AUTHOR]

Background: Chemodynamic therapy (CDT), employing Fenton or Fenton-like catalysts to convert hydrogen peroxide (H2O2) into toxic hydroxyl radicals (·OH) to kill cancer cells, holds great promise in tumor therapy due to its high selectivity. However, the therapeutic effect is significantly limited by insufficient intracellular H2O2 level in tumor cells. Fortunately, β-Lapachone (Lapa) that can exert H2O2-supplementing functionality under the catalysis of nicotinamide adenine dinucleotide (phosphate) NAD(P)H: quinone oxidoreductase-1 (NQO1) enzyme offers a new idea to solve this problem. However, extensive DNA damage caused by high levels of reactive oxygen species can trigger the "hyperactivation" of poly(ADP-ribose) polymerase (PARP), which results in the severe interruption of H2O2 supply and further the reduced efficacy of CDT. Herein, we report a self-amplified nanocatalytic system (ZIF67/Ola/Lapa) to co-deliver the PARP inhibitor Olaparib (Ola) and NQO1-bioactivatable drug Lapa for sustainable H2O2 production and augmented CDT ("1 + 1 + 1 > 3"). Results: The effective inhibition of PARP by Ola can synergize Lapa to enhance H2O2 formation due to the continuous NQO1 redox cycling. In turn, the high levels of H2O2 further react with Co2+ to produce the highly toxic ·OH by Fenton-like reaction, dramatically improving CDT. Both in vitro and in vivo studies demonstrate the excellent antitumor activity of ZIF67/Ola/Lapa in NQO1 overexpressed MDA-MB-231 tumor cells. Importantly, the nanocomposite presents minimal systemic toxicity in normal tissues due to the low NQO1 expression. Conclusions: This design of nanocatalytic system offers a new paradigm for combing PARP inhibitor, NQO1-bioactivatable drug and Fenton-reagents to obtain sustained H2O2 generation for tumor-specific self-amplified CDT. [ABSTRACT FROM AUTHOR]

CO 2 capture and utilisation (CCU) is a promising strategy to effectively mitigate the adverse greenhouse effects caused by CO 2 emissions at an industrial scale. Through a process intensification strategy known as integrated CO 2 capture and utilisation (ICCU), CO 2 capture and catalytic CO 2 conversion can be achieved in a single process with the use of dual function materials (DFMs), which are both CO 2 sorbents and CO 2 conversion catalysts. Given the significantly different operating conditions of ICCU from conventional catalytic CO 2 hydrogenation, the catalytic mechanism of DFMs, especially during CO 2 hydrogenation, needs to be thoroughly investigated. In this study, the relationship between the nature of the Ni/carbonate interfaces and the performance of Ni-based DFMs over ICCU cycles is systematically investigated. A series of Ni/alkaline earth carbonate DFMs were synthesised with varying Ca:Mg ratios to simulate different metal-carbonate model interfaces. At 400 °C, CH 4 formation with nearly 100% CH 4 selectivity was achieved on Ni/CaCO 3 over 15 ICCU cycles. In general, Ni/CaCO 3 interfaces correspond to higher CO 2 conversion and higher CH 4 selectivity than Ni/MgCO 3 interfaces. Such trend may be attributed to the higher surface basicity of CaO and the higher thermal stability of CaCO 3. As a consequence, the hydrogenation of the Ni/CaCO 3 interface proceed via the formate pathway, in which carbonates are consecutively converted to surface formates, methoxyl, methyl species and eventually desorb as methane. This reaction model is applicable to the hydrogenation of both surface carbonate and bulk carbonates, although the former proceeds with much faster kinetics. On the weakly alkaline Ni/MgCO 3 interface, MgCO 3 preferentially decomposes to form gaseous CO 2 , which is subsequently hydrogenated via the reverse-water-gas-shift pathway, with CO as the key reaction intermediate. Interestingly, in situ infrared spectroscopy shows similar surface significant species during the direct hydrogenation of DFMs and during the conventional catalytic hydrogenation of molecular CO 2 , suggesting that the catalytic mechanisms during the two operating regimes are highly correlated. [Display omitted] • Novel Ni/carbonate dual function materials for CO 2 capture and hydrogenation. • Different hydrogenation behaviour and pathway on Ni/CaCO 3 and Ni/MgCO 3 interfaces. • Two reaction regimes proposed during hydrogenation of Ni/CaCO 3. • Suitable basic sites and metal-support interaction favours the hydrogenation. • Correlation between ICCU cycles and those of conventional CO 2 hydrogenation. [ABSTRACT FROM AUTHOR]

G-series nerve agents, such as sarin, tabun, and soman, would cause tremendous harm in military and terrorist attacks, so it is necessary to develop a simple method for the rapid and efficient detection of these hazardous substances. We have developed a tunable acetylcholinesterase (AChE)-functionalized two-dimensional photonic crystal (2D PhC) for the detection of a real nerve agent, sarin. In accordance with the 2D PhC previously prepared by our group, the AChE-functionalized 2D PhC was optimized by adjustment of the amount of monomer in the hydrogel, which not only increased the sensitivity of the 2D PhC, with the detection limit decreasing by two orders of magnitude, but also ensured the structural color spanned the whole visible region in the detection range. A linear relationship between the logarithm of the sarin concentration and the particle spacing of the AChE-functionalized 2D PhC was observed from 7.1 × 10-17 to 7.1 × 10-4 mol/L. The AChE-functionalized 2D PhC also responded to mimics of G-series nerve agents, including dimethyl methylphosphonate, diisopropyl methylphosphonate, and isodipropyl methylphosphonate, to various degrees. The proposed 2D-PhC hydrogel has potential for low-cost, trace-level, and on-site monitoring of other G-series nerve agents. Graphical abstract [ABSTRACT FROM AUTHOR]

A kind of typical metal-organic frameworks (MOFs) material, HKUST-1 was prepared by hydrothermal method and characterized by XRD and SEM. The results of characterizations manifested that HKUST-1 showed a regular octahedral crystal structure. The as-prepared HKUST-1 was modified by several kinds of organic base materials and the 2 adsorption behaviors of modified HKUST-1 materials were evaluated. The 2 adsorption capacities of different base modified HKUST-1 varied with the base intensity of modified organic base materials. [ABSTRACT FROM AUTHOR]

Abstract: A novel biosensor is developed based on immobilization of proteins on nanoflake-like SnS2 modified glass carbon electrode (GCE). With glucose oxidase (GOD) as a model, direct electrochemistry of the GOD/nanoflake-like SnS2 is studied. The prepared SnS2 has large surface area and can offer favorable microenvironment for facilitating the electron transfer between protein and electrode surface. The properties of GOD/SnS2 are characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR) and cyclic voltammetry (CV), respectively. The immobilized enzyme on nanoflake-like SnS2 retains its native structure and bioactivity and exhibits a surface-controlled, reversible two-proton and two-electron transfer reaction with the apparent electron transfer rate constant (k s) of 3.68s−1. The proposed biosensor shows fast amperometric response (8s) to glucose with a wide linear range from 2.5×10−5 M to 1.1×10−3 M, a low detection limit of 1.0×10−5 M at signal-to-noise of 3 and good sensitivity (7.6±0.5mAM−1 cm−2). The resulting biosensor has acceptable operational stability, good reproducibility and excellent selectivity and can be successfully applied in the reagentless glucose sensing at −0.45V. It should be worthwhile noting that it opens a new avenue for fabricating excellent electrochemical biosensor. [Copyright &y& Elsevier]

Background: Several works suggest the importance of autophagy during esophageal carcinoma development. The aim of the study is to construct a scoring system according to the expression profiles of major autophagy-related genes (ARGs) among esophageal carcinoma cases.Methods: The Cancer Genome Atlas was employed to obtain the esophageal carcinoma data. Thereafter, the online database Oncolnc ( http://www.oncolnc.org/ ) was employed to verify the accuracy of our results. According to our results, the included ARGs were related to overall survival (OS).Results: We detected the expression patterns of ARG within esophageal carcinoma and normal esophageal tissues. In addition, we identified the autophagy related gene set, including 14 genes displaying remarkable significance in predicting the esophageal carcinoma prognosis. The cox regression results showed that, 7 ARGs (including TBK1, ATG5, HSP90AB1, VAMP7, DNAJB1, GABARAPL2, and MAP2K7) were screened to calculate the ARGs scores. Typically, patients with higher ARGs scores were associated with poorer OS. Moreover, the receiver operating characteristic (ROC) curve analysis suggested that, ARGs accurately distinguished the healthy people from esophageal carcinoma patients, with the area under curve (AUC) value of > 0.6.Conclusion: A scoring system is constructed in this study based on the main ARGs, which accurately predicts the outcomes for esophageal carcinoma. [ABSTRACT FROM AUTHOR]