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Polyurea coating and carbon fibre reinforced polymer reinforcing techniques were applied to retrofit a severely damaged urban utility tunnel (UUT). The blast responses of the retrofitted UUT were investigated through in-filed explosion experimental tests, and the displacements, strains, accelerations, and damage were compared. The retrofitted UUT exhibited comparable or even better blast resistance than the intact UUT. Although the polyurea coating was flexible, it exhibited excellent performance in improving the blast resistance of the damaged UUT. As the UUT reinforced with basalt fibre reinforce polymer (BFRP) bars has smaller damage compared with the UUT reinforced with steel bars, its retrofitting is simple, and the cost is low. The roof was simplified as an elastically simple support one-way slab. Euler beam theory was adopted to analyse the dynamic responses of UUT roof considering the interaction between soil and structure, which agree well with the experiments in the first three cases.

A new 1D phosphorescence coordination polymer (CP) [Pb2O(C6H4NO2)2]n (1; C6H4NO2 = nicotinate) was synthesized by a solvothermal reaction and PbO was used as a Pb(II) source instead of traditional Pb(II) salts. This remarkably thermal-stable CP crystallizes in the space group I41/a. In the crystal structure of 1, two different Pb(II) ions show a five-coordinated and hemidirected coordination geometry, two nonequivalent nicotinate ligands link to Pb(II) ions in μ2–η1:η1 and μ4–η2:η2 modes, and the hemidirected coordination polyhedra of Pb(II) form a helical lead-oxide chain via an edge-sharing fashion along the c-axis. Under ambient conditions, 1 emits cyan ligand-based phosphorescence with an absolute quantum yield as high as 59.4% and a lifetime of 9.86 ms under UV-light irradiation. Under the same conditions, nicotinic acid emits simultaneously fluorescence and phosphorescence with a total absolute quantum yield of 4.8%. The great enhancement of phosphorescence quantum yield in 1, regarding nicotinic acid, is assigned to the heavy atom effect of Pb(II) and negligible π⋯π interaction between pyridyl rings. Noticeably, the vibronic fine structure is observed in the emission spectrum of 1 at room temperature. Additionally, 1 shows thermochromic behavior, and such functionality probably has realistic application in the field of temperature detection.

A new 2D phosphorescence lead metal cluster-based coordination polymer (CP) [Pb4(μ2-OH) (μ3-OH) (μ4-O) (3-qlc)4]n (1; 3-qlc ​= ​3-quinolinecarboxylate) has been successfully synthesized by solvothermal reaction. CP 1 is a robust Pb(II) CP constructed by a rare [Pb8(μ2-OH)2 (μ3-OH)2 (μ4-O)2(COO)8] cluster units and 3-qlc ligands. The bulky clusters provide architectural stability to the framework of 1. Interestingly, CP 1 exhibited almost pure room-temperature orange phosphorescence with absolute phosphorescence quantum yields of 3.3% and a phosphorescence lifetime of 1.52 ​ms benefiting from the restriction of molecular vibrations/rotations of organic luminogens (3-qlc) and the heavy-atom effect of Pb(II).

A series of Cu–Zn–Al–Zr precursor materials are prepared by coprecipitation at different pH values (6.0–11.0) and treated under hydrothermal condition. Zincian malachite is formed as the main phase at the low pH of 6.0 and 7.0, and is replaced by hydrotalcite-like phases with increasing the pH. After calcination and reduction of precursors, Cu/ZnO/Al2O3/ZrO2 catalysts are obtained and tested for methanol synthesis from CO2 hydrogenation at the reaction temperature of 463 K. With increasing pH, the Cu particle size first increases until pH 9.0 and then decreases. Compared with the sample resulting from well-crystallized zincian malachite (pH 7.0), the catalysts derived from phase-pure hydrotalcite-like precursors (pH ≥ 9.0) exhibit lower BET specific surface area and lower specific Cu surface area. In addition, due to the smaller of Cu particle size and the stronger interaction among Cu and ZnO, the catalytic activity for the Cu/ZnO/Al2O3/ZrO2 catalysts via the hydrotalcite-like precursors is higher than that for the catalysts derived from zincian malachite precursors at low reaction temperature. A maximum CH3OH yield of 0.087 g gcat−1 h−1 with the CO2 conversion of 10.7% and the CH3OH selectivity of 81.8% at 463 K and 5.0 MPa is obtained over the Cu/ZnO/Al2O3/ZrO2 catalyst prepared at pH 9.0.

Viral corneal infection is a common cause of visual impairment and blindness. Polyinosinic‑polycytidylic acid, or poly(I:C), is similar to viral double‑stranded RNA in structure and has been implicated in the release of a variety of cytokines, chemokines and matrix metalloproteinases (MMPs) by corneal fibroblasts. Sulforaphane (SFN) is an isothiocyanate compound found in cruciferous vegetables. The present study investigated the potential effect of SFN on the poly(I:C)‑stimulated release of cytokines, chemokines and MMPs in human corneal fibroblasts (HCFs). ELISA showed that SFN was associated with a time‑ and dose‑dependent reduction in poly(I:C)‑stimulated production of interleukin (IL)‑8, chemoattractant protein‑1, IL‑6, MMP‑1 and MMP‑3 by HCFs. Western blot analysis indicated that SFN suppressed the function of poly(I:C) by modulating mitogen‑activated protein kinases (MAPKs), including p38 and extracellular signal‑regulated kinase (ERK), activator protein‑1 (AP‑1) component c‑Jun and the kinase, Akt, and the phosphorylation and degradation of the nuclear factor (NF)‑κB inhibitor IκB‑α. Immunofluorescence analysis revealed that SFN attenuated the production of poly(I:C)‑induced nuclear translocation of the NF‑κB p65 subunit. Reverse transcription‑quantitative PCR analysis revealed that SFN prevented the poly(I:C)‑induced upregulation of Toll‑like receptor 3 (TLR3) mRNA expression in HCFs. No significant cytotoxic effect of SFN on HCFs was observed. In summary, SFN attenuated the poly(I:C)‑induced production of proinflammatory chemokines, cytokines and MMPs by HCFs, by inhibiting TLR3, MAPK (p38 and ERK), AP‑1, Akt and NF‑κB signaling. SFN may therefore be a potential novel treatment for viral corneal infection by limiting immune cell infiltration.

Kaolinite, one of the most ubiquitous clay minerals on the earth, is a hydrated aluminum disilicate with the composition of Al2Si2O5(OH)4, 1:1 dioctahedral and structurally asymmetric layers. This type of lamella mineral provides a platform to create artificially functional materials. Herein, we present a facile approach to prepare the glowing Kaolinites via a stepwise of intercalation of Kaolinite with N-Methyl imidazole (abbr. NMI) and Eu3+/Tb3+ nitrate salts in sequence, which are labeled as K-NMI-Eu and K-NMI-Tb, respectively, and characterized by microanalysis, thermogravimetric (TG), IR spectroscopy, powder X-ray diffraction techniques. Under ultraviolet irradiation, K-NMI-Eu and K-NMI-Tb emit the characteristic luminescence of Eu3+/Tb3+ ion with quantum yields of 25.5% (Eu3+) and 16.3% (Tb3+), respectively. We further fabricated the composite films of K-NMI-Eu with polyvinylidene fluoride (PVDF), K-NMI-Eu@PVDF-X (X = 1, 2, 5 and 10%, representing the mass percentage of K-NMI-Eu in film). The mechanical performances of composite films are almost the same as that of the pure PVDF film even if the X value is up to 10%. K-NMI-Eu@PVDF-10% emits intense red luminescence under ultraviolet irradiation at ambient condition, indicating that K-NMI-Eu is a good ultraviolet-converted-red light material potentially used for the agricultural light conversion film.

AIM: To determine if triptolide influences the contractility and fibronectin production in human Tenon fibroblasts (HTFs). METHODS: HTFs were cultured in type I collagen gels with or without transforming growth factor beta (TGF-β) and/or triptolide. The diameter of the collagen gel was used to measure contraction. Immunoblot analysis was used to quantify myosin light chain (MLC) phosphorylation and integrin expression. Laser confocal fluorescence microscopy was used to monitor the formation of actin stress fibers. Fibronectin production was measured with an enzyme immunoassay. RESULTS: Triptolide inhibition of contraction in TGF-β-induced collagen gel mediated by HTFs was dose-dependent and statistically significant at 3 nmol/L (P

Two mixed-valence Mn(II,IV) complexes, [MnII4MnIV3(teaH)3(tea)(thmeH)3(thme)](ClO4)2·3MeCN (1) and [MnII2MnIV2(edteH)2(peolH)2]·4MeOH (2), where H4edte = N,N,N′,N′-tetrakis(2-hydroxyethyl)ethylenediamine, teaH3 = tris(2-hydroxyethyl)amine, H4peol = pentaerythritol, and H3thme = 1,1,1-tris(hydroxymethyl)ethane, were prepared from the corresponding manganese salts and mixed ligands with polyalcohols. The two clusters consist of a trapped-valence polynuclear core comprising 4MnII and 3MnIV for 1, 2MnII and 2MnIV ions for 2. Complex 1 crystallizes in the rhombohedral space group R3c, while 2 crystallizes in the monoclinic space group P21/c. Complex 1 consists of a near-planar Mn7 unit that comprises a Mn6 hexagon of alternating MnII and MnIV ions surrounding a central MnII ion. The remaining coordinated sites are occupied by eight different deprotonation degrees of H3tea or H3thme. The tetranuclear cluster of 2 consists of a fused defective dicubane Mn4O6 core, and the four Mn ions are coordinated by oxygens from edteH3− and peolH3− into an unusual butterfly-like [MnII2MnIV2] topology. The two clusters are also characterized by mass spectra and X-ray photoelectron spectroscopy. Direct current magnetization studies reveal ferromagnetic interactions within both Mn clusters.

The hydrothermal reactions of 5-bromoisophthalic acid (H 2 BIPA) and metal salts in the presence of pyridine (py) result in three new coordination polymers, namely, M(BIPA)(py) 3 [M = Co(II) ( 1 ), Ni(II) ( 2 )] and Zn(BIPA)(py) 2 ·H 2 O ( 3 ), all of which have been characterized by single-crystal X-ray, elemental analysis, infrared spectroscopy, and thermogravimetric analysis. Compounds 1 and 2 are isostructural and contain 2 1 helical chains made up of metal ions and BIPA 2− ligand, the chains are further formed to the supramolecular structures by the π⋯π interactions between the adjacent parallel py rings. Compound 3 has a 1D chiral left-handed helical chain structure. It is notable that 3 is obtained by second order spontaneous resolution using achiral starting materials. Moreover, the solid-state CD spectrum of single crystals and powder samples of 3 is investigated. The nonlinear optical measurement shows that 3 displayed a second-harmonic-generation (SHG) response of 0.7 times that for urea.

[Tb2(1,2-pdoa)3 · 6H2O] · H2O (1) and [La(1,2-pdoa)(1,2-H2pdoa)(OH) · H2O] · 5H2O (2) (1,2-H2pdoa = 1,2-phenylenedioxydiacetic acid) have been synthesized and structurally characterized by single crystal X-ray diffraction. Complex 1 is a binuclear molecule in which one 1,2-pdoa ligand is a tetradentate bridge linking two Tb3+ ions, the other two 1,2-pdoa ligands bond Tb13+ and Tb1A3+ via tetradentate chelating coordination. Tb3+ is nine-coordinate by six oxygens of 1,2-pdoa and three waters. Complex 2 is mono-nuclear with La3+ ten-coordinate by eight oxygens of two 1,2-pdoa, one hydroxide and one water. 1,2-Pdoa is tetradentate chelating with La3+ ion. The packing diagrams of 1 and 2 show supramolecular networks via H-bonds. The fluorescence spectrum of 1 shows characteristic emission of Tb3+ with 5D4 → 7Fj (j = 6–3) transitions.

Treatment of Ln(NO3)3 · 6H2O with 1, 2-phenylenedioxydiacetic acid (H2PDOA) in ethanol leads to the unusual 1-D double chain complexes {[Ln(PDOA)1.5 (H2O)3] · H2O}n (Ln = Sm (1), Eu (2), Dy (3)), in which the Ln3+ ions are linked by pentadentate and bideatate PDOA ligands in two different directions. The chain looks like a ladder containing two –Ln–O–C–O–Ln– chains and PDOA spacers, which has never been observed in the lanthanide carboxylate complexes, and they exhibit different photoluminescence properties.

A coordination polymer {[Tb 4 (3-SBA) 4 (OH) 4 (phen) 3 (H 2 O) 3 ] · 7H 2 O} n (3-SBA = 3-sulfobenzoate, phen = 1,10-phenanthroline) was synthesized and structurally characterized. The complex contains cubane-like clusters, [Tb 4 (μ 3 -OH) 4 (phen) 3 (H 2 O) 3 ] 8+ , which are further linked through 3-SBA ligands to form a 2-D grid-like network structure with topology of (3 3 , 4 4 , 5 3 ). The complex exhibits strong photoluminescence of the Tb 3+ ion.

Two lanthanide coordination polymers, [Ln2(dpdc)3(H2O)2] n (Ln = Sm 1, Dy 2; dpdc = 2,2′-diphenyldicarboxylate) were prepared by hydrothermal reaction and characterized by elemental analyses, IR spectroscopy, thermogravimetry, fluorescence spectrometry, and single-crystal X-ray diffraction. X-ray studies indicate that the two complexes are isostructural, with two different lanthanide ion nodes linked by dpdc ligands into an infinite one-dimensional chain structure, in which dpdc ligands are bidentate-bridging/bidentate-bridging and bidentate-bridging/chelate-bridging. Complexes 1 and 2 exhibit luminescent characteristics of Sm(III) and Dy(III) ions, respectively.

Two complexes {[Dy2(4-SBA)3(phen)2(H2O)4] · 2H2O}n (1) and {[Eu2(4-SBA)3(phen)2(H2O)2]}n (2) (4-SBA = 4-sulfobenzoate, phen = 1,10-phenanthroline) were synthesized and their structures were determined by X-ray crystallography. The 1 has a 1-D chain structure by bidentate and tridentate 4-SBA ligands as linkages and 3-D network was formed by strong hydrogen bonds. The 2 has a 2-D network structure by tridentate and tetradentate 4-SBA ligands as linkages. The luminescence properties and thermal stability of the two complexes were investigated.

Objective : The aim was to determine if inducible nitric oxide synthase (iNOS) contributes to depressed cardiovascular function at the acute phase of streptozotocin-induced diabetes. Methods : Male Wistar rats were injected with streptozotocin [60 mg/kg, intravenously (i.v.)] or the vehicle (0.9% NaCl) and were studied 3 weeks later. Results : The diabetic and control rats had similar mean arterial pressure (MAP) and total peripheral resistance (TPR). Noradrenaline (NA) increased in vivo left ventricular contractility (LV +dP/dt), MAP and TPR in both groups; however, the responses were markedly less in the diabetic than control rats. Acute administration of 1400W (selective inhibitor of iNOS; 3 mg/kg followed by 3 mg/kg/h, i.v.) did not alter responses to NA in the control rats, but augmented the influence of NA on MAP, TPR and LV +dP/dt in the diabetic rats. At this time, reverse transcription–polymerase chain reaction (RT-PCR) products (RNA) of iNOS were present in the hearts of the diabetic but not control rats. The activity of iNOS was threefold higher in the hearts of the diabetic rats relative to the controls, and the increase was inhibited by 1400W. Furthermore, immunostaining (proteins) of iNOS and nitrotyrosine (NT; marker of peroxynitrite) were identified in the hearts of the diabetic but not control rats. In contrast, the RT-PCR products of eNOS, activity of eNOS and immunostaining of eNOS were of similar intensity in the hearts of both groups. Conclusions : Activation of iNOS contributes to depressed cardiovascular contractile function to NA at the acute phase of streptozotocin-induced diabetes. Selective inhibition of iNOS partially restored cardiovascular responses to NA.