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Wideband and polarization-insensitive operation are key issues for electro-optic modulators. An electro-absorption modulator based on graphene-silicon nitride hybrid waveguide has been proposed. Geometric parameters are investigated through finite element method to enhance the interaction between the optical mode and the graphene. For a 200-µm-long hybrid waveguide, a modulation depth (MD) of 20 dB can be obtained when Femi level varies from 0.2 to 0.6 eV. The MD difference between the transversal electric polarization and transversal magnetic polarization (ΔMD) can be restrained to 4 × 10−3 dB at 1550 nm. A low average ΔMD of 0.2 dB within the wavelength range from 1100 to 1645 nm can be obtained. The 3 dB-bandwidth of 53 GHz and a power consumption is 0.687 pJ/bit can be obtained. The proposed modulator has potentials for on-chip signal processing.

A polymer waveguide mode selecting switch (MSS) composed of two cascaded MMI couplers is demonstrated. The MSS can switch different data channels over $\text{E}_{\mathbf {00}}$ and $\text{E}_{\mathbf {10}}$ modes. Polymer waveguide dimensions are optimized with beam propagation method. The simulated results indicate that the worst insertion loss is 5.5 dB at 1550 nm and the switching powers for $\text{E}_{\mathbf {10}}$ mode between two different channels are 4.5 and 12.3 mW, respectively. The extinction ratio and crosstalk are less than 19.7 and −19.6 dB, respectively. The switching performances of fabricated MSS prove the functionality of proposed design, which promises its potentials in mode-division-multiplexing applications.

Metal-free direct α-C(sp3)−H intramolecular cyclization of 2-alkylthiobenzoic acid in the presence of Selectfluor is described. This novel strategy provides a facile and efficient method to access important 1,3-benzooxathiin-4-one derivatives with good functional groups tolerance and yields.

The design and construction of an artificial light-harvesting system in water by mimicking the energy transfer cascade in natural photosynthesis are of significant importance. Herein, we report an efficient two-step sequential energy transfer system based on quadruple hydrogen-bonded supramolecular polymeric nanoparticles. By loading two types of hydrophobic dyes as energy acceptors, excitation energy from the supramolecular polymer could be funneled efficiently to the final acceptor through the relay acceptor. The system exhibits tunable multicolor emission from blue through yellow to red, as well as white light emission.

The direct acyloxyation of 2-(alkylthio)benzamide has been established via the amide-assisted α-C(sp3)–H functionalization in the presence of Selectfluor by employing simple carboxylic acid and its corresponding salt as acyloxy sources. This novel and simple method is characterized by its broad substrate scope in moderate to good yields and excellent functional group compatibility. Furthermore, this method also provides a complementary strategy to access important α-acyloxy sulfides and their derivatives.

A novel upper-rim functionalized calix[4]squaramide organocatalyst bearing bis-squaramide and cyclohexanediamine scaffolds was designed and prepared to catalyse a serial of asymmetric Michael addition of 1,3-dicarbonyl compounds to α,β-unsaturated carbonyl compounds in high yields (up to 99 %) and good to excellent enantiomeric excesses (up to 99% ee). The comparative experiments indicated that the cooperative effect between calixarenes cavitives and chiral catalytic centers on this calix[4]squaramide catalyst could promote these reactions. Moreover, this strategy also provides valuable and easy access to chiral chromene, naphthoquinone and acetylacetone derivatives, which are important skeletons in biological and pharmaceutical compounds.

Supramolecular polymers constructed by orthogonal self–assembly based on multiple hydrogen bonding and macrocyclic host–guest interactions have received increasing attention due to their elegant structures, outstanding properties, and potential applications. Hydrogen bonding endows these supramolecular polymers with good adaptability and reversibility, while macrocyclic host–guest interactions give them good selectivity and versatile stimuli-responsiveness. Therefore, functional supramolecular polymers fabricated by these two highly specific, noninterfering interactions in an orthogonal way have shown wide applications in the fields of molecular machines, electronics, soft materials, etc. In this review, we discuss the recent advances of functional supramolecular polymers fabricated by orthogonal self-assembly based on multiple hydrogen bonding and host–guest interactions. In particular, we focus on crown ether- and pillar[n]arene-based supramolecular polymers due to their compatibility with multiple hydrogen bonds in organic solution. The fabrication strategies, interesting properties, and potential applications of these advanced supramolecular materials are mainly concerned. Download : Download high-res image (104KB) Download : Download full-size image

Allosteric effects are common in biology, but have not been fully explored in the control of supramolecular polymerization. Herein, ditopic UPy derivatives with acyclic crown ether-like spacers were designed and synthesized, which can undergo supramolecular polymerization through quadruple hydrogen bonding. Upon the addition of K+, drastic molecular conformational change to the U-shape is induced by metal-coordination, reconfiguring remote UPy sites towards the formation of discrete cyclic dimers. Interestingly, the supramolecular polymerization can be restored by simply removing K+ by water-extraction.

A silicon waveguide mode (de)multiplexer is theoretically proposed for compact on-chip mode (de)multiplexing (MDM). The (de)multiplexing of E 11 y , E 21 y , E 31 y , E 12 y , E 22 y and E 32 y modes is realized by cascading asymmetric Y-junctions and the E 21 y ∕ E 12 y mode rotators. Beam propagation method is adopted in the design and optimization. For a 124 μ m-long device, the mode crosstalk among all channels is less than -24 dB. The insertion loss can be lowered to 0.96 dB at optical wavelength of 1550 nm. This proposed design method can be extended to the construction of higher-order mode (de)MUX.

Angiostrongylus cantonensis (AC), which parasitizes in the brain of the non-permissive host, such as mouse and human, is an etiologic agent of eosinophilic meningitis. Excretory-secretory (ES) products play an important role in the interaction between parasites and hosts’ immune responses. Inflammatory macrophages are responsible for eosinophilic meningitis induced by AC, and the soluble antigens of Angiostrongylus cantonensis fourth stage larva (AC L4), a mimic of dead AC L4, aggravate eosinophilic meningitis in AC-infected mice model via promoting alternative activation of macrophages. In this study, we investigated the key molecules in the ES products of AC L4 on macrophages and observed the relationship between metabolic reprogramming and the PI3K-Akt pathway. First, a co-culture system of macrophage and AC L4 was established to define the role of AC L4 ES products on macrophage polarization. Then, AC L4 exosome and exosome-depleted excretory-secretory products (exofree) were separated from AC L4 ES products using differential centrifugation, and their distinct roles on macrophage polarization were confirmed using qPCR and ELISA experiments. Moreover, AC L4 exofree induced alternative activation of macrophages, which is partially associated with metabolic reprogramming by the PI3K-Akt pathway. Next, lectin blot and deglycosylation assay were done, suggesting the key role of N-linked glycoproteins in exofree. Then, glycoproteomic analysis of exofree and RNA-seq analysis of exofree-treated macrophage were performed. Bi-layer PPI network analysis based on these results identified macrophage-related protein Hexa as a key molecule in inducing alternative activation of macrophages. Our results indicate a great value for research of helminth-derived immunoregulatory molecules, which might contribute to drug development for immune-related diseases.

Compact high-performance electro-optic (EO) modulators are key elements for optical communications. An electro-absorption modulator is theoretically designed. Due to the introduction of graphene film over the silicon slot waveguide, the modulation efficiency is strongly improved. The effect of waveguide dimensions, dielectric insulator thickness, and carrier mobility on performances of the proposed EO modulator have been comprehensively investigated. For the 120-μm-long graphene-on-silicon waveguide modulator, the extinction ratio 28 dB and insertion loss 1.28 dB can be obtained at 1550 nm when drive voltage is 1.91 and 0.59 V, respectively. The 3 dB bandwidth of 117 GHz can be obtained at a small power consumption of 212 fJ/bit. The proposed modulator possesses a high figure-of-merit of 20.5. Its benefits of small size, power saving, and process compatible promises possible applications in on-chip signal processing.

Background Experimental studies have demonstrated that both the extracellular vasculature or microenvironment and intracellular molecular network (e.g., epidermal growth factor receptor (EGFR) signaling pathway) are important for brain tumor growth. Additionally, some drugs have been developed to inhibit EGFR signaling pathways. However, how angiogenesis affects the response of tumor cells to drug treatment has rarely been mechanistically studied. Therefore, a multiscale model is required to investigate such complex biological systems that contain interactions and feedback among multiple levels. Results In this study, we developed a single cell-based multiscale spatiotemporal model to simulate vascular tumor growth and the drug response based on the vascular endothelial growth factor receptor (VEGFR) signaling pathway, the EGFR signaling pathway and the cell cycle as well as several microenvironmental factors that determine cell fate switches in a temporal and spatial context. By incorporating the EGFRI treatment effect, the model showed an interesting phenomenon in which the survival rate of tumor cells decreased in the early stage but rebounded in a later stage, revealing the emergence of drug resistance. Moreover, we revealed the critical role of angiogenesis in acquired drug resistance, since inhibiting blood vessel growth using a VEGFR inhibitor prevented the recovery of the survival rate of tumor cells in the later stage. We further investigated the optimal timing of combining VEGFR inhibition with EGFR inhibition and predicted that the drug combination targeting both the EGFR pathway and VEGFR pathway has a synergistic effect. The experimental data validated the prediction of drug synergy, confirming the effectiveness of our model. In addition, the combination of EGFR and VEGFR genes showed clinical relevance in glioma patients. Conclusions The developed multiscale model revealed angiogenesis-induced drug resistance mechanisms of brain tumors to EGFRI treatment and predicted a synergistic drug combination targeting both EGFR and VEGFR pathways with optimal combination timing. This study explored the mechanistic and functional mechanisms of the angiogenesis underlying tumor growth and drug resistance, which advances our understanding of novel mechanisms of drug resistance and provides implications for designing more effective cancer therapies. Electronic supplementary material The online version of this article (10.1186/s12859-019-2737-1) contains supplementary material, which is available to authorized users.

An efficient DBU-catalyzed Michael reaction of enones with 1,3-diketones has been developed for the gram-scale preparation of the Michael adducts. It is attractive that most of the adducts can be obtained with high purity through simple filtration. A convenient I2-mediated transformation of the adducts to polysubstituted phenols has also been exploited. This conversion is remarkable with the cyclization and aromatization processes by using DBU as the base and I2 as the oxidant. Furthermore, hydroxylated (E)-stilbene derivatives can be easily prepared by using this method. The readily available starting materials, metal-free and mild conditions make this approach simple and practical.

Here we report our research on biomimetic folding architectures self-assembled hierarchically from well-designed UPy-based monomers with low molecular weight (MW < 400 Da). These monomers are first dimerized via quadruple hydrogen bonding and then form folded dimers with the assistance of π–π interactions. More interestingly, the folded dimer further formed one-dimensional supramolecular stacks through additional weak π–π interactions in the solid state. Similar to DNA, these well-defined structures are stabilized by the concerted hydrogen bonding and π–π interaction in a synergistic manner, which would provide inspiration for constructing biomimetic self-folding materials.

The control of supramolecular polymerization is of high fundamental significance for understanding self-assembly processes at the nanoscale. It also remarkably affects the design and improves the efficiency of dynamic polymer materials. To this end, we have developed an effective strategy which employs a type of non-covalent interaction to orthogonally regulate the supramolecular polymerization driven by another non-covalent interaction. Specifically, we herein report the quadruple hydrogen bond-driven supramolecular polymerization controlled by the assistance of the π–π interaction. A series of aromatic group bridged ditopic ureidopyrimidinone (UPy) derivatives (M1, M2, and M3) were designed and successfully synthesized. These molecules could self-assemble into cyclic monomers or linear supramolecular polymers under different conditions via quadruple hydrogen bonding. By additionally introducing a π–π interaction into the cyclic monomers, which exists between the aromatic group and the dimerized UPy motifs, a ring-opening supramolecular polymerization process based on ring-chain equilibrium can be preliminarily controlled due to the adjustable strength of the π–π interaction. These findings could offer new perspectives into orthogonal self-assembly and provide model systems for the studies of fundamental supramolecular polymer physics.

The relationship between molecular structure and macroscopic characteristics is a fundamental issue for materials design. Some minor changes in molecular structure may have a great impact on the molecular self-assembly process. Therefore, it is of interest to design new isomeric building blocks for supramolecular self-assembly, offering inspiration for the development of smart materials by supramolecular engineering. In this study, two dioxynaphthalene (DNP) group bridged bifunctional ureidopyrimidinone (UPy) monomers (DNP1 and DNP2) were synthesized. The chemical structures of the two isomers are very similar and the only difference is that DNP1 is 2,6-substituted and DNP2 is 1,5-substituted on the DNP motif. Interestingly, these two isomers exhibit completely different supramolecular self-assembly behaviors. Highly viscous supramolecular polymers were obtained in a concentrated solution of DNP1, while crystals based on highly stable cyclic monomers were precipitated from a concentrated solution of DNP2. Since DNP is an electron rich group, the host–guest behaviors of DNP1 and DNP2 with a blue-box were further studied, which also showed different ring-threading capabilities.

A tunable copper-catalyzed reaction of C60 with 2-ethoxycarbonylacetamides using air as the oxidant has been explored, which selectively affords methanofullerenes (2) and dihydrofuran-fused fullerenes (3) under the CuI/DMAP and CuCl/NMI catalytic systems, respectively. Furthermore, the generated dihydrofuran-fused fullerenes could be transformed to fulleropyrrolidinones (4 and 5) upon treatment with BF3·Et2O.

Straight long-range surface plasmon polariton (LRSPP) waveguides are demonstrated as liquid refractive index (RI) sensors (Barnes et al. in Nat Mater 424:824–830, 2003, [1]). The sensors consist of 5 μm-wide, 20 nm-thick straight Au stripes that are embedded in ultraviolet (UV) sensitive polymer SU-8. The double layer liftoff fabrication is adopted to fabricate the embedded rectangular and smooth Au stripes. An etched microfluidic channel allows the contact of analyte to Au surface for RI detection. Within the range from 1.576 to 1.596, a sensitivity of 821 dB/RIU can be obtained. The proposed device has potentials in the portable and compact refractometer application.

Background: Diabetic cardiomyopathy (DCM) is the main cause of increased mortality in Diabetes mellitus (DM). There are no effective therapeutic strategies. Recently, we found that DM is associated with the upregulation of β 3 adrenergic receptor (AR) mediated cardiac inhibitory pathway. This suggests cardiac β 3 -AR activation may contribute to DCM progression and be a therapeutic target. We hypothesize that upregulation of β 3 -AR is maladaptive, and DM-caused progressive decline in cardiac function and β-adrenergic reserve will be prevented in β 3 -AR knockout (β 3 KO) mice. Methods: Studies were conducted in female mice of 2 Vehicle controls groups (n=8/group) of wild-type (CWT) and Cβ 3 KO, and 2 Type 2 DM (T2) of T2WT (n=8) and T2β 3 KO (n=6).T2 was induced by fed high-fat diet (HFD) for 14 weeks (W), but after HFD for 4 W receiving streptozotocin (STZ, 40 mg/kg/day, i.p. for 5 days). We compared LV myocyte contractile and [Ca 2+ ] iT responses to β-AR subtype stimulation by random exposure of myocytes to the superfusion of isoproterenol (ISO,10 -8 M) or a selective β 1 -, or β 3 -agonist, Norepinephrine (NE, 10 -7 M), and BRL-37,344 (BRL, 10 -8 M), respectively. Results: Mice received HFD plus STZ developed T2DM with elevated mean blood glucose from 128 mg/dl of control to 388 mg/dl and 382 mg/dl in T2WT and T2β 3 KO, respectively. However only T2WT mice developed DCM followed by significant decreases in myocyte contraction (dL/dt max , T2WT: 74.8 vs CWT:140.1 μm/s), relaxation (dR/dt max , 58.0 vs 117.9 μm/s) and [Ca 2+ ] iT (0.16 vs 0.22). ISO-stimulated increases in dL/dt max (37% vs 58%), dR/dt max (30% vs 53%), and [Ca 2+ ] iT (19% vs 30%) were attenuated accompanied by a diminished NE-caused increase in dL/dt max (28% vs 41%), but enhanced BRL-induced decrease in dL/dt max (29% vs 15%). By contrary, T2β 3 KO showed normal basal dL/dt max (137.6 μm/s), dR/dt max (111.4 μm/s) and [Ca 2+ ] iT (0.22). Importantly, T2β 3 KO myocytes showed preserved ISO-stimulated increases in dL/dt max (60%), dR/dt max (51%) and [Ca 2+ ] iT (32%) and restored normal dL/dt max responses to NE (41%). Conclusions: β 3 KO prevents T2DM-caused contrast changes in β 1 - and β 3 -AR-stimulated cardiac inotropic actions and leading to the preservation of normal myocyte function, [Ca 2+ ] iT , and β-AR responsiveness in DCM.

Background: Transgenic rats expressing the human angiotensinogen gene [TGR (hAogen) 1623] (hAogen) exhibit sustained hypertension and systolic dysfunction associated with altered cardiac renin-angiotensin system and β- adrenergic receptor (AR) signal transduction systems. We have shown previously, in contrast to β 1 - and β 2 -ARs, β 3 -ARs are linked to G i proteins, and stimulation of β 3 -ARs inhibits cardiac contraction and relaxation. Hypertension is associated with increased cardiac expression of G i proteins. This may alter β 3 -AR stimulation and play an important role in the cardiac functional impairment of this humanized model of hypertension. However, the alteration and functional effect of β 3 -AR activation in this model are unknown. We tested the hypothesis that high cardiac tissue Ang II content in hAogen may cause an up-regulation of cardiac β 3 -AR, which exacerbates myocyte dysfunction and impairs calcium regulation, thereby directly contributing to the cardiac dysfunction. Methods: We compared LV myocyte β 3 -AR expression and myocyte functional and [Ca 2+ ] i transient ([Ca 2+ ] iT ) responses to β- and β 3 -AR stimulation in myocytes obtained from 8 Sprague Dawley (SD) control and 8 hAogen male adult rats. Results: Versus SD, in hAGT rats, basal myocyte contraction (dL/dt max , 107.1 vs 138.8 μm/s), relaxation (dR/dt max , 94.0 vs 103.9 μm/s) and [Ca 2+ ] iT (0.15 vs 0.21) were depressed. A non-selective β-AR agonist, isoproterenol (ISO) (10 -8 M) produced significantly smaller increases in dL/dt max , (42% vs. 61%), dR / dtmax (35% vs. 51%), and [Ca 2+ ] iT (20% vs. 30%). Moreover, versus SD, in hAogen rats, LV myocyte β 3 -AR protein level increased by 32% (0.29 vs 0.22) with resulted significantly altered myocyte functional response to β 3 -AR stimulation. Compared with the changes in SD myocytes, in hAogen myocytes, BRL (10 -8 M) produced a significantly greater decreases in dL/dt max , (27% vs 12%), dR/dt max (28% vs 11%), and [Ca 2+ ] iT (17% vs 10%). Conclusions: TGR (hAogen) 1623, this humanized model of hypertension is associated with an up-regulation of LV myocyte β 3 -AR, which enhances β 3 -AR-caused inhibition of myocyte contractile, relaxation and [Ca 2+ ] iT and exacerbates β-AR desensitization, thereby directly contributing to the cardiac dysfunction.

Background: Angiotensin-(1-12) [Ang-(1-12)] is a chymase-dependent source for Angiotensin II (Ang II) inotropic activity that may be impaired in a model of sustained hypertension with high cardiac Ang II content due to insertion of the human angiotensinogen (AGT) gene in the rat genome. Accordingly, we evaluated the effects of Ang-(1-12) and Ang II on myocyte contractility and [Ca 2+ ] i regulation in 9 adult male transgenic rats expressing the human AGT gene [TGR(hAGT)L1623)] and 9 SD controls. Methods: We compared LV myocyte contraction, relaxation and [Ca 2+ ] i transient ([Ca 2+ ] iT ) responses to Ang-(1-12) (4x10 -6 M) and Ang II (10 -6 M) in freshly isolated LV myocytes. Results: Myocyte contraction (dL/dt max , 109.6 vs 127.9 μm/s), relaxation (dR/dt max , 95.3 vs 107.5 μm/s) and [Ca 2+ ] iT (0.15 vs 0.24) were depressed in TGR(hAGT)L1623 rats compared to SD controls. Moreover, cell contractile and [Ca 2+ ] iT responses following exposure to Ang-(1-12) or Ang II were markedly blunted. In SD myocytes, versus baseline, Ang II or Ang-(1-12) superfusion produced significant increases in dL/dt max [Ang II: 44% vs Ang-(1-12): 34%], dR/dt max (33% vs 26%) and [Ca 2+ ] iT (31% vs 25%). Importantly, the magnitude of the responses to the two agents in TGR(hAGT)L1623 myocytes was significantly reduced. Versus the changes in SD myocytes, Ang-(1-12) caused significantly less increases in dL/dt max (22%), dR/dt max (16%) and [Ca 2+ ] iT (15%) in TGR(hAGT)L1623 myocytes . Ang II also caused similar significantly attenuated increases in dL/dt max (27%), dR/dt max (25%) and [Ca 2+ ] iT (23%). The Ang-(1-12)-induced inotropic effects were completely prevented in the presence of the inhibitory cAMP analog, Rp-cAMPS (10 –4 M, 2 hours) in both SD and TGR(hAGT)L1623 myocytes, but were further augmented only intransgenic rats after incubation of myocytes with the G i inhibitor, pertussis toxin (PTX, 2 μg/ml, 36°C, 5 hours). Conclusions: Ang-(1-12) stimulates LV myocyte contractile function and [Ca 2+ ] iT in both SD and TGR(hAGT)L1623 rats. Furthermore, we now show that the blunted inotropic responses to Ang-(1-12) and Ang II in rats expressing the human AGT gene is mediated through a cAMP-dependent mechanism that is coupled to both stimulatory G and inhibitory PTX-sensitive G proteins.

Background: Recent evidence links impaired nitric oxide (NO) signaling pathway in the pathogenesis of diabetes-induced cardiac dysfunction. However, the different nitric oxide synthases (NOS) isoforms involved in this pathology are controversial. Recent reports have shown that in failing myocardium, increased inducible NOS (iNOS) contributes to the attenuation of β-adrenergic receptor (AR)-mediated inotropic effect. The alteration and functional significance of cardiac iNOS in diabetic cardiomyopathy (DCM) are unclear. We assessed the hypothesis that increased cardiomyocyte iNOS expression and stimulation may inhibit myocyte contraction, relaxation, [Ca 2+ ] i transient ([Ca 2+ ] iT ), and depress its response to β-AR stimulation, thereby directly contributing to the functional impairment in DCM. Methods: Left ventricular (LV) myocyte protein levels of 3 NOS and myocyte functional responses were evaluated in 2 groups of wild-type female mice (11/group): control and DCM-induced by streptozotocin (STZ) (at 10 weeks after receiving 200 mg/kg STZ, ip). In DCM, we further assessed myocyte contractile and ([Ca 2+ ] iT ) responses to β-AR stimulation by isoproterenol (ISO, 10 -8 M) with and without pretreatment of myocytes with a selective iNOS inhibitor, 1400W (10 -5 M). Results: Compared with controls, DCM myocytes had significantly increased iNOS (1.76 vs 1.03) with decreased eNOS (0.29 vs 0.34), but relatively unchanged nNOS (0.17 vs 0.18). These changes were followed by significantly reduced basal cell contraction (dL/dt max , 73.8 vs 140.7 μm/s), relaxation (dR/dt max , 61.5 vs 121.1 μm/s) and [Ca 2+ ] iT (0.17 vs 0.20). ISO-stimulated increases in dL/dt max (32% vs 59%), dR/dt max (30% vs 55%) and [Ca 2+ ] iT (17% vs 31%) were also significantly reduced. Moreover, in DCM myocytes, pretreatment with 1400W markedly improved myocyte basal contraction (128.0 μm/s) and relaxation (111.7 μm/s). The ISO-induced increases in dL/dt max (55%), dR/dt max (52%), and [Ca 2+ ] iT (29%) were also significantly augmented. Conclusions: Our findings indicate that myocardial iNOS is activated in diabetic mice and suggest that increased iNOS expression contributes to depressed myocardial contractility, impaired [Ca 2+ ] i regulation and β-adrenergic hyporesponsiveness.

With the aid of CTAB amphiphile, water-phase artificial light-harvesting systems were fabricated as nanoparticles by the self-assembly of two low-molecular-weight organic molecules: a UPy-functionalized TPE derivative 1 with both supramolecular polymerization and AIE capabilities as a donor and a fluorescent chromophore NiR as an acceptor. Owing to the flexibility of supramolecular self-assembly, tunable emissions including white-light emission could be easily realized with high energy transfer efficiency and the antenna effect.

Fusarium graminearum is the major causal agent of Fusarium head blight (FHB) disease in cereal crops worldwide. Infection with this fungal phytopathogen can regularly cause severe yield and quality losses and mycotoxin contamination in grains. In previous other studies, one research group reported that pyrrolnitrin had an ability to suppress of mycelial growth of F. graminearum. Other groups revealed that phenazine-1-carboxamide, a derivative of phenazine-1-carboxylic acid, could also inhibit the growth of F. graminearum and showed great potentials in the bioprotection of crops from FHB disease. In our recent work with Pseudomonas chlororaphis strain G05, however, we found that although the phz operon (phenazine biosynthetic gene cluster) was knocked out, the phenazine-deficient mutant G05Δphz still exhibited effective inhibition of the mycelial growth of some fungal phytopathogens in pathogen inhibition assay, especially including F. graminearum, Colletotrichum gloeosporioides, Botrytis cinerea. With our further investigations, including deletion and complementation of the prn operon (pyrrolnitrin biosynthetic gene cluster), purification and identification of fungal compounds, we first verified that not phenazines but pyrrolnitrin biosynthesized in P. chlororaphis G05 plays an essential role in growth suppression of F. graminearum and the bioprotection of cereal crops against FHB disease.

In this paper, an integrated processing method was demonstrated to fabricate the polymer-based thermo-optic (TO) switch with low power consumption. The characteristic parameters of the switch were carefully designed and simulated. The air trench structure was exploited to reduce the power consumption, which can be formed with the waveguide simultaneously by the integrated processing method. Moreover, the introduced polymer/silica hybrid waveguide structure can also improve the response time of the device. A typical fabricated switch presented a low switching power of 5.2 mW. The measured switching rise time and fall time are 192.2 and 201.1 μs, respectively.

A number of upper rim-functionalized calix[4]thiourea cyclohexanediamine derivatives have been designed, synthesized and used as catalysts for enantioselective Michael addition reactions between nitroolefins and acetylacetone. The optimal catalyst 2 with a mono-thiourea group exhibited good performance in the presence of water/toluene (v/v = 1:2). Under the optimal reaction conditions, high yields of up to 99% and moderate to good enantioselectivities up to 94% ee were achieved. Detailed experiments clearly showed that the upper rim-functionalized hydrophobic calixarene scaffold played an important role in cooperation with the catalytic center to the good reactivities and enantioselectivities.

A novel oxo-spirocyclic structure bridged ditopic Schiff base fluorescent probe L has been successfully synthesized and characterized. Interestingly, probe L exhibits a specific turn-on response to zinc(II) ion in fluorescence with a high selectivity and sensitivity. Further study show that probe L could be applied in imaging of live cells for sensing zinc(II) ion. By contrast, those compounds (L1, L2, and L3) with very similar structure to L lack this properties. The fluorescence intensity of L increases with Zn2+, which is less affected by other metal ions. The binding property of L with Zn2+ was studied by a combination of technologies, such as Job's plot, 1H NMR, ESI-MS, and DFT calculations. Moreover, we have successfully applied the probe L to detect Zn2+ in cancer cell. We are anticipating that this new oxo-spirocyclic structure bridged ditopic Schiff base may provide a new idea for the design of fluorescent probe.

Catalytic hydrogenation of nitrophenols to aminophenols was considered as the most efficient way to solve their contamination together with huge economic benefit. NiCo2S4 can be used not only as supercapacitor materials, but also competitive catalytic materials in hydrogenation reactions. In this work, a nitrogen-doped carbon black (NCB) supported NiCo2S4 catalyst is successfully prepared by a facile one-pot solvothermal approach. TEM results show that the ultrafine NiCo2S4 particles are uniformly dispersed on the surface of NCB at a low NiCo2S4 loading, while aggregation may occur in NiCo2S4/NCB catalysts with an excessive NiCo2S4 content. The NiCo2S4-30/NCB catalyst with a BET surface area of 47.20 m2 g−1 exhibits the most excellent catalytic activity and durability for heterogeneous catalytic hydrogenation of nitrophenols using NaBH4 as the reducing agent at 30 °C in the aqueous solution. The kinetic constant of hydrogenation of p-nitrophenol catalyzed by NiCo2S4-30/NCB is almost five times higher than the reaction catalyzed by pristine NiCo2S4. The outstanding performance of NiCo2S4-30/NCB is ascribed to the unique nanostructure of the catalyst and the combined effect between the NiCo2S4 and NCB, including abundant surface functional groups of NCB for anchoring and dispersing NiCo2S4, strong adsorption ability for nitrophenol molecules facilitated by π–π stacking interaction, as well as fast electron transfer from NCB to NiCo2S4, resulting in higher local electron densities and thus facilitating the uptake of electrons by nitrophenols.

In the current work, the aim is to report systematic results from first-principles calculations with density functional theory (DFT) on three cubic structures, rock salt (NaCl-type), zinc blende (ZnS-type), and cesium chloride (CsCl-type), of ZnN under high pressure. From the enthalpy versus pressure relations, we find that the NaCl-type phase of ZnN is more stable than the ZnS-type phase when the pressure higher than 2.55 GPa and high-pressure NaCl-type phase will stabilize up to 150 GPa. Through the careful evaluation with the quasi-harmonic Debye model, a complete set of thermodynamic data up to 2000 K, including PVT equation of state, isothermal bulk modulus, Debye temperature, Gruneisen parameter, thermal expansivity, heat capacity, and entropy for the ZnN with high-pressure NaCl-type structure is achieved. This set of data is considered as the useful information to understand the high-temperature and high-pressure properties of ZnN.

A NH4I/ tert-butyl hydroperoxide-promoted oxidation of tertiary N-aryl- N,N-dialkylamines in DMSO has been developed to access nitroaromatic compounds. This methodology involves sequential N-dealkylation reactions in one-pot and a radical pathway is proposed.

Lewis base-catalyzed double nucleophilic substitution reaction of N -tosylaziridinofullerene with thioureas or guanidines affords the fullerothiazolidin-2-imine or fulleroimidazolidin-2-imine derivatives, respectively. In the case of unsymmetrical thioureas connecting an alkyl and an aryl group on each of the nitrogen atom, the transformation exhibits excellent chemoselectivity with only the aryl substituted nitrogen atom bonding to C 60 . The generated tri-4-methoxyphenyl substituted fulleroimidazolidin-2-imine reacts with CS 2 smoothly to generate di-4-methoxyphenyl fulleroimidazolidin-2-thione.

CuI-catalyzed diverse functionalizations of C60 with amino alcohols with aerobic oxygen as the sole oxidant have been explored. For 2-/3-amino alcohols, an aminooxygenation reaction occurs to generate fulleromorpholine and fullerooxazepane derivatives. When a tethered furan ring exists, a further intramolecular [4 + 2] reaction with the neighboring double bond occurs to furnish the cis-1 products. In the case of 4-/5-amino alcohols, methanofullerenes linking with cyclic amides are obtained through cyclic enamine intermediates.

A milder, more regioselective and practical approach to C3 or O-alkylation reaction of 4-hydroxycoumarins has been established. Both 2H-[3,2-c] furocoumarins and 4-hydroxycoumarin vinyl ether derivatives could be efficiently prepared by alkylating 4-hydroxycoumarins with electron-deficient allenoates catalyzed by PPh3 and DBU, respectively. The reaction outcomes can be controlled by changing the catalysts, starting with the same reaction substrates. Possible reaction mechanisms have also been proposed

Thermal expansion coefficient, heat capacity, and Gruneisen parameter of iridium phosphide Ir2P are reported by means of quasi-harmonic Debye model for the first time in the current study. This model combines with first-principles calculations within generalized gradient approximation using pseudopotentials and a plane-wave basis in the framework of density functional theory, and it takes into account the phononic effects within the quasi-harmonic approximation. The Debye temperature as a function of volume, the Gruneisen parameter, thermal expansion coefficient, constant-volume and constant-pressure heat capacities, and entropy on the temperature T are also successfully obtained. All the thermodynamic properties of Ir2P in the whole pressure range from 0 to 100 GPa and temperature range from 0 to 3000 K are summarized and discussed in detail.

A first optical resolution of 6,12-diphenyldibenzo[b,f][1,5]diazocine with stable boat conformation was achieved by chiral supercritical fluid chromatography (SFC). The absolute configurations of enantiomers were first assigned and determined by X-ray crystal structure based on CIP-rules. The high optical rotation and circular dichroism spectrum were well explained by electronic helix theory. Owing to the high stabilization of boat conformation, the chiral configuration could be maintained at very high temperature, more than 200 °C, which was proved by Density Functional Theory calculations.

A base-controlled formal [3 + 2] cycloaddition of 1,3-dicarbonyl compounds to enones via an I 2 -mediated cyclization was reported. Highly functionalized dihydrofurans and furans were selectively obtained under I 2 /DMAP and I 2 /DBU conditions in the cyclization step, respectively.

A series of upper rim-functionalized calix[4]arene-based l -Proline derivatives have been synthesized and employed for the enantioselective aldol reactions between cyclic ketones and aromatic aldehydes in the presence of water. Good to excellent yields (up to 96%), enantioselectivities (up to 99% ee ), as well as diastereoselectivities (up to 99:1 dr ) were obtained under the optimal reaction conditions. Detailed experiments clearly showed that the hydrophobic calixarene platform not only contributed to the good reactivities and enantioselectivities, but also exhibited size-selective catalysis function. Moreover, the organocatalyst can be readily recovered and reused for several runs without significant loss in its enantioselectivity.

A novel flake composite benzenoid-like CuFeO 2 @reduced graphene oxide (CuFeO 2 @RGO) was fabricated via a one-step low temperature solvothermal route. The obtained samples were characterized by XRD, FTIR, Raman, SEM, TEM and XPS, which indicated that the hexagonal CuFeO 2 nanocrystals sized 150–200 nm were well dispersed on the surface of the RGO sheets. For the first time, we applied such CuFeO 2 @RGO composite as a Fenton-like catalyst in selective oxidation of phenol to dihydroxybenzenes with H 2 O 2 as oxidant. The results showed that the CuFeO 2 @RGO composite exhibited remarkably enhanced catalytic ability compared with the previously reported CuFe 2 O 4 –RGO system. The introduction of RGO in the composite was propitious to increase the specific surface area and promoted the dispersibility of CuFeO 2 nanocrystals, as well as the formation of unique hexagonal CuFeO 2 with Cu (I) and Fe (III) as the active sites, which synergistically accounted for the enhancement of catalytic activity. Moreover, the stability of the catalyst was investigated.

The Cs2CO3-catalyzed reaction of 2-oxindoles with enones affords 2,2-disubstituted indolin-3-ones through domino “Michael addition–oxidation–ring-cleavage–C–N coupling” process. O2 acts as the sole oxidant to accomplish the oxidative process. The indolin-3-ones can be further transformed to pyridazine, azirdine-fused 3-oxindoles, 4-quinolone derivatives easily.

Supramolecular vesicles have attracted considerable attention due to their advantages of facile construction, high-cargo-loading capacity, and good biocompatibility. Pillar[n]arenes are a unique family of supramolecular macrocycles, exhibiting excellent features and broad applications due to their intrinsic topology and high functionality. In the past decade, the construction of pillar[n]arene-based supramolecular vesicles has been continuously attempted and developed rapidly. In this review, we mainly summarize the significant advancements of such supramolecular vesicles in the last three years. By showing some representative examples, the design strategies, construction methods, and potential applications of these dynamic nanocarriers are discussed in detail. In particular, the responsiveness of such vesicles to various external stimuli and their applications in drug delivery are highlighted. The outstanding performance of pillar[n]arene-based supramolecular vesicles would definitely enrich the family of supramolecular vesicles and promote the development of dynamic supramolecular materials.

Herein an aqueous-phase artificial light-harvesting platform has been constructed based on the self-assembly of three small organic molecules: a rigid acetal-based spirocyclic skeleton bridged tetraphenylethylene dimer as donor, a hydrophobic dye molecule Nile Red as acceptor, and the surfactant cetyltrimethyl ammonium bromide as amphiphile to enwrap the donor and acceptor and disperse them in water. Due to the rigid skeleton of the tetraphenylethylene dimer that can well accommodate and distribute Nile Red inside the self-assembled nanospheres, the system shows ultrahigh light-harvesting antenna effects. Moreover, by simply tuning the donor/acceptor molar ratio, tunable emission including a bright white-light emission could be realized.