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Positive cooperative binding, a phenomenon prevalent in biological processes, holds great appeal for the design of highly sensitive responsive molecules and materials. It has been demonstrated that metal-organic frameworks (MOFs) can show positive cooperative adsorption to the benefit of gas separation, but potential binding cooperativity is largely ignored in the study of sensory MOFs. Here, we report the first demonstration of positive cooperative protonation of a MOF and the relevant pH response in fluorescence and proton conduction. The MOF is built of Zr-O clusters and bipyridyl-based tetracarboxylate linkers and has excellent hydrolytic stability. It shows a unique pH response that features two synchronous abrupt turn-off and turn-on fluorescent transitions. The abrupt transitions, which afford high sensitivity to small pH fluctuations, are due to cooperative protonation of the pyridyl sites with a Hill coefficient of 1.6. The synchronous dual-emission response, which leads to visual color change, is ascribable to proton-triggered switching between (n, π*) and (π, π*) emissions. The latter emission can be quenched by electron donating anion-dependent through photoinduced electron transfer and ground-state charge transfer. Associated with cooperative protonation, the proton conductivity of the MOF is abruptly enhanced at low pH by two orders, but overhigh acid concentration is adverse because excessive anions can interrupt the conducting networks. Our work shows new perspectives of binding cooperativity in MOFs and should shed new light on the development of responsive fluorescent MOFs and proton conductive materials.

Sensory materials that show color and/or fluorescence changes in response to specific gases or vapors have important applications in many fields. Here, we report the postsynthetic preparation of novel sensory metal-organic frameworks (MOFs) and their multiple responsive properties. Through postsynthetic N-amination, the 2,2'-bipyridyl spacers in a Zr(IV) MOF are partially transformed into N-aminobipyridinium. The new MOF (Zr-bpy-A) shows chromic behavior toward ammonia and amines because the electron-deficient pyridinium groups form charge-transfer complexes with amino moieties. It also shows a unique chromic response to formaldehyde owing to the Schiff-base condensation with the N-amino groups. Furthermore, the N-amino group can be used to graft different polycyclic aromatic hydrocarbons, which endow the MOF with strong fluorescence of variable colors and afford a high-contrast fluorescence response to ammonia/amines and formaldehyde associated with the chromic response. The presence of the unquaternized bipyridyl group also leads to a fluorescence response to HCl. The multiple responsive behaviors hold appeal for applications in sensing, switching, and antifake marking, which are illustrated with a test paper and writing ink.

Solid catalysts for CO2 cycloaddition to epoxides often require homogeneous halide anions in large amounts, which sacrifice the heterogeneity and ecofriendliness. Here, we demonstrate a novel appro...

The chiral phosphoric acid catalyzed regio-, diastereo- and enantioselective reaction of isoxazol-5(4H)-ones with β,γ-alkynyl-α-imino esters has been developed. With the established methodology, γ-addition of β,γ-alkynyl-α-imino esters and C-allenylation of isoxazol-5(4H)-ones were achieved with high regio- and stereoselectivities, affording diverse α-imino allenoates featuring an adjacent quaternary carbon stereocenter and an axially chiral tetrasubstituted allene motif in high yields.

A novel Eu(III) metal–organic framework (MOF) featuring 3-fold interpenetration shows multi-responsive behaviors owing to the combination of charge transfer, electron transfer, and energy transfer between different ingredients (the electron-deficient tris(pyridinium)triazine (tpt) chromophore, the electron-rich naphthalene chromophore, the Eu(III) luminophore, and the guest anion). The interframework naphthalene-to-tpt charge transfer dictated by framework interpenetration serves to sensitize the Eu(III) emission through energy transfer. The photoinduced host–guest electron transfer from the intrinsic chloride guest to tpt leads to photochromism and photoquenching of photoluminescence. The spontaneous host–guest electron transfer from extrinsic amine/ammonia to tpt allow chromic and luminescent response to ammonia and amines with size selectivity. Furthermore, the photogenerated phase shows sensitive color change and luminescence turn-on upon exposure to O2. The multi-responsive properties offer the appeal for optical switching and sensing use. The qualitative and quantitative gaseous sensing of ammonia and O2 has been demonstrated with portable and reusable MOF–polymer membranes.

Stretchable elastomers with superhydrophobic surfaces have potential applications in wearable electronics. However, various types of damage inevitably occur on these elastomers in actual application, resulting in the deterioration of the superhydrophobic properties. In this work, superhydrophobic elastomers (HB-imine-BZn-PDMS), was fabricated by employing a dual-layered structure. The bottom layer was a silicon elastomer (imine-BZn-PDMS) with an imine/coordination dual cross-linked structure and room temperature self-healing efficiency of 94%. The top layer was imine-BZn-PDMS/silica nanocomposites to provide superhydrophobic properties. The HB-imine-BZn-PDMS elastomer exhibited fast triple self-healing ability at room temperature toward surface oxidation/decomposition, ruptures, or pinholes, and high durability under abrasion and stretching. The dual dynamic bonds of imine-BZn-PDMS enabled fast recovery of superhydrophobicity in 20 min at room temperature via bond exchange, after generating pinholes across the elastomer. Following surface chemical damage, the HB-imine-BZn-PDMS elastomer also exhibited fast (40 min) room-temperature self-healing ability, which is superior to that of most current self-healing superhydrophobic materials.

Remote stereocontrolled 1,8-addition of heteroatom nucleophiles to 6-methylene-6H-indoles generated in situ from 6-indolylmethanols has been developed for the first time. With the aid of a chiral phosphoric acid, 6-indolylmethanols reacted with benzotriazoles to furnish 1,8-adducts with a nitrogen-containing tertiary carbon stereocenter in 54-80% yield with 76-92% ee. Importantly, the stereoselective 1,8-addition of benzotriazoles featured N2 selectivity. Furthermore, using thioacids as nucleophiles enabled the formation of 1,8-adducts with a sulfur-containing tertiary carbon stereocenter in 70-78% yield with 75-94% ee.

Kinase inhibitor selectivity is a major concern for the design of small-molecule compounds. As a member of serine/threonine protein kinase family, glycogen synthase kinase 3β (GSK3β) is involved in diverse biological processes and abnormal dysregulation of its activity has been associated with several pathologies, including type II diabetes, Alzheimer’s disease, bipolar disorders, and cancers. A small-molecule PF-367 significantly inhibited the GSK3 enzymatic activity over its closest cyclin-dependent kinase 2 (CDK2) with >1000-fold selectivity. However, the PF-367 selectively binding to GSK3β over CDK2 has remained unclear. Here, molecular docking, molecular dynamics (MD) simulations, and molecular mechanics_generalized born/surface area (MM_GBSA) binding free energy calculations, as well as the decomposition of binding free energies were performed to investigate the selective binding mechanism of PF-367 to the ATP-binding site of GSK3β over CDK2. The results revealed that the exposure of the terminal triazole ring of PF-367 into the solvent environment may be responsible for the weak binding complex of CDK2−PF-367, which was further confirmed by the binding free energy calculations and the identified key residues (Phe67, Lys85, Thr138, and Arg141) contributing to the binding interaction. The obtained data can not only decipher the origin of selectivity, but also be used for the design of more potent and selective GSK3β inhibitors.

As one of the most promising alternatives for future energy systems, the rechargeable Zn–air battery (ZAB) has attracted extensive attention due to its extraordinarily high theoretical specific energy density. However, several obstacles restrict its practical application. One challenge is the sluggish kinetics of oxygen-reduction reaction (ORR) and oxygen-evolution reaction (OER) in the discharging and charging processes of ZABs. In addition, when using unifunctional ORR or OER electrocatalysts as air electrodes, like noble metal catalysts (Pt/C or Ru/IrO2), there are the disadvantages of high cost and poor stability. Therefore, rational design of non-noble metal bifunctional ORR/OER electrocatalysts with high activity and stability is essential for the development of ZABs. In this review, we discuss the latest developments of non-noble metal bifunctional ORR/OER electrocatalysts for ZABs. Firstly, the related reaction mechanisms of ORR and OER are introduced. Then, the latest developments of bifunctional ORR/OER materials for ZABs are discussed in detail from three aspects: (i) MOF-based catalysts, including pristine MOFs and their derivatives; (ii) metal-free-based carbon catalysts, including heteroatom-doped carbon and defective carbon; (iii) metal-based catalysts, including metal–nitrogen–carbon materials (such as metals/alloys, single-atom) and metal compound materials. Finally, some challenges and outlooks for the optimal design of bifunctional air electrodes for rechargeable ZABs with high activity and ultra-long lifetime are put forward.

Coordination polymer submicrospheres were successfully synthesized using a solvothermal method using organophosphate (HDEHP) and Y(NO3)3 without any additional ligand and surfactant under mild conditions. Upon calcination, the obtained precursor produced stable tetragonal phase (t-)YPO4 submicrospheres. XRD, SEM and HRTEM were used to characterize the precursor and calcined samples. The results showed that t-YPO4 submicrospheres were obtained by the thermal decomposition of the precursor, and there was no other phase transition in the process. FTIR and TG-DTA confirmed that the precursor was a coordination polymer formed by HDEHP and Y3+, and the growth process of the spherical precursor was proposed. Furthermore, various REPO4 (RE = La–Lu, except radioactive Pm) spherical particles and the Eu3+ doped YPO4 phosphor were synthesized under similar conditions. The luminescent properties of the YPO4:Eu phosphor were also studied in detail.

A two-dimensional Cd(ii) metal-organic framework (MOF) was constructed from a tris(pyridinium)-based hexacarboxylate zwitterionic ligand. The MOF shows a novel fashion of 2-fold 2D → 2D parallel entanglement. It is the entanglement that dictates close interlayer contacts between carboxylate (electron donor) and pyridinium (acceptor), which in turn impart the MOF with reversible photochromic properties through photoinduced electron transfer (PET). This is an extension of PET-based photochromism from bipyridinium to multipyridinium compounds. Thanks to the photoresponsive behaviour, the fluorescence of the MOF can be reversibly modulated or switched by photoirradiation. Besides, the fluorescence of the water-stable MOF in aqueous dispersion is very sensitive to nitrofuran antibiotics with high selectivity, and therefore the MOF is a good candidate of efficient and regenerable sensing material for determination of the antibiotics in water media.

A novel metal-organic framework (MOF), formulated as [Cd2(TTVTC)Cl2(H2O)3]·2H2O (1), was synthesized from a tetracarboxylate ligand ([TTVTC]2-) functionalized with the thiazolothiazole extended viologen (TTV2+) fluorophore. The MOF features three-dimensional (10,3)-d frameworks with 6-fold interpenetration. The MOF exhibits reversible photochromism, due to photoinduced electron transfer from carboxylate to TTV2+. The photoactivity benefits from the electron donor-acceptor contacts enabled by mutual interpenetration of the frameworks. This is the first demonstration of photochromism in TTV2+ derivatives. In addition, the fluorescence arising from the TTV2+ fluorophore can be reversibly modulated during the photochromic process. The work demonstrates the great potential of extended viologen based ligands in the construction of MOFs with dual photomodulable optical properties, which could find future applications in photoelectronics.

This study investigated polycyclic aromatic hydrocarbons (PAHs) and soot formation characteristics in laminar jet flames fuelled by primary reference fuels (PRFs) at elevated pressures. Qualitative PAHs and quantitative soot profiles were acquired by using laser-induced fluorescence and laser-induced incandescence, respectively. The backpressure of flames ranged from 1 bar to 5 bar. Proper flames with the volume fraction of iso-octane in PRFs varying between 0% and 100% and flame equivalent ratio varying between 3.0 and 11.4 were stabilised in a pressurised chamber. The effects of backpressure, equivalent ratio and iso-octane ratio on PAHs and soot formation were evaluated. PAHs and soot formation can be promoted by increasing iso-octane ratio, equivalent ratio and backpressure. The data suggest that PAHs with large molecular size are more sensitive to the increase of backpressure compared with those with small molecular size. Backpressure played a positive role in the growth of PAHs size. The averaged soot volume fraction showed an approximate power-law relation with pressure. The measured averaged soot volume fraction was proportional to pn. Pressure exponent n was 1.34–2.17, 1.41–2.12 and 1.56–2.20 at equivalent ratios of 6.2, 8.5 and 11.4, respectively.

Fouling is a common challenge to all membrane-based separation technologies. The current study demonstrated an antifouling membrane with a superhydrophilic but oleophobic (in air) characteristic, which was achieved through covalently tethering heterogeneously tailored two-dimensional layered double hydroxide (LDH) nanosheets to a polyvinylidene fluoride membrane surface. The nanosheets were in situ grafted with alternately arranged sodium 1-dodecanesulfonate (SDS) and 3-aminopropyltriethoxysilane (APTS) chains during preparation. Poly(methacrylic acid) (PMAA) was previously grafted on the membrane via plasma induced graft copolymerization as anchor sites for nanosheet binding. With a simple dip-coating operation, the surface-tailored LDH nanosheets could be bound to the membrane via cross-linking between the amine groups of APTS and carboxyl groups of PMAA. Ultimately, the long hydrophobic SDS and short hydrophilic APTS chains on the nanosheets formed a heterogeneous and infiltration selective (due to steric exclusion) surface on the membrane. As a result, the hydrophilic moieties on the membrane surface were much more accessible to water than to liquids of larger molecular size, thereby bringing about the superhydrophilic but oleophobic characteristic. The functionalization gave rise to both significantly enhanced wettability and hydrophilicity of the membrane, mainly owing to the increase of the electron donor component of surface energy (γAB−). Additionally, the functionalized membrane obtained a greater permeability without compromising its selectivity. Furthermore, as verified in both filtration tests with synthetic and practical foulant solutions, the superhydrophilic and oleophobic characteristic endowed the functionalized membrane with conspicuously greater cleaning efficiency and excellent capability in resisting irreversible fouling, suggesting promising applications in various fields.

The assembly of two tripyridinium-tricarboxylate ligands and different metal ions leads to seven isostructural MOFs, which show novel 2D→2D supramolecular entanglement featuring catenane-like interlocking of tricyclic cages. The MOFs show tripyridinium-afforded and metal-modulated photoresponsive properties. The MOFs with d10 metal centers (1-Cd, 1-Zn, 2-Cd, 2-Zn) show fast and reversible photochromism and concomitant fluorescence quenching, 1-Ni displays slower photochromism but does not fluoresce, and 1-Co and 2-Co are neither photochromic nor fluorescent. It is shown here that the network entanglement dictates donor-acceptor close contacts, which enable fluorescence originated from interligand charge transfer. The contacts also allow photoinduced electron transfer, which underlies photochromism and concomitant fluorescence response. The metal dependence in fluorescence and photochromism can be related to energy transfer through metal-centered d-d transitions. In addition, 1-Cd is demonstrated to be a potential fluorescence sensor for sensitive and selective detection of UO22+ in water.

This paper studies the feature extraction and middle-level expression of Convolutional Neural Network (CNN) convolutional layer glass broken and cracked at the scene of road traffic accident. The image pyramid is constructed and used as the input of the CNN model, and the convolutional layer road traffic accident scene glass breakage and crack characteristics at each scale in the pyramid are extracted separately, and then the depth descriptors at different image scales are extracted. In order to improve the discriminative power of the depth descriptor, Hellinger kernel and Principal Component Analysis (PCA) are used to perform nonlinear and linear transformations. Two aggregation strategies based on depth descriptors are proposed to form a global image representation. The classification experiment of the data set shows that Hellinger kernel, PCA transformation, and two aggregation strategies are all conducive to improving the classification accuracy. In addition, the convolutional layer road traffic accident scene glass breaking and crack feature coding can obtain better classification performance than the fully connected layer feature. We conducted dynamic impact tests on plate glass and Polyvinyl Butyral- (PVB-) laminated glass under different boundary conditions and studied the crack propagation and failure process of the glass under different impact speeds. The results show that there are radial cracks and circular cracks on the glass specimens under the impact load; the glass specimens show partial damage under high-speed impact and the characteristics of glass breaking and cracks at the scene of road traffic accidents; the four-frame plate glass is supported by sharp dagger-like fragments. This paper compares the energy absorption of glass specimens under different boundary conditions. The results show that the energy absorption effect of the four-point supporting glass specimen is generally stronger than that of the four-frame supporting glass.

The aim of this study was to investigate the effect of 20 mg/L 2,4-D on the quality during ripening of on-tree longan fruits. We investigated external and internal properties of the on-tree longan fruits. The results showed that 2,4-D treatment promotes the growth based on the fruit size and weight. The respiration rate, contents of TSS, total soluble sugar, sucrose, glucose, fructose, and hexose revealed an increasing tendency with advancing the maturity and reached the high status during 110-126DPA. By contrast, the relative electric conductivity and TA content displayed a declining trend during the ripening stage, increase with the senescence. All these pieces of information indicated that 2,4-D treatment could effectively promote the sensory quality of on-tree longan fruit, prolong the harvest time to 118DPA, while CK should harvest before 110DPA.

Due to its great relevance to environmental, biological, and chemical processes, the precise detection of pH or acidic/basic species is an ongoing and imperative need. In this context, pH-sensitive luminescent systems are highly desired. We reported a three-dimensional Zn(II) MOF synthesized from a bipyridyl-tetracarboxylic ligand and composed of 4-fold interpenetrated diamond frameworks. Because the steric hindrance in the ligand prevents metal coordination with the pyridyl group, the MOF features free basic N sites accessible to the small H+ ions, which renders pH responsivity. The aqueous dispersion exhibits an abrupt, high-contrast, and reversible on-off fluorescence transition in the narrow pH range of 5.4-6.2. The sensitive bistable system can be used for the precise monitoring of pH within the range and for use as a pH-triggered optical switch. The responsive mechanism through pyridyl protonation is collaboratively supported by data fitting, absorption spectra, and molecular orbital calculations. In particular, spectral and theoretical analyses reveal the destruction of n → π* transitions and the appearance of intramolecular charge-transfer transitions upon pyridyl protonation. Moreover, by virtue of the pH-responsive fluorescence, the MOF shows appealing sensing performance for the detection of 3-nitropropionic acid, a major mycotoxin in moldy sugar cane.

Previous studies have shown an attenuating effect of ginsenoside Re on myocardial injury induced by hypoxia/reoxygenation (H/R). However, the underlying mechanism remains unclear. This study was designed to determine the underlying mechanism by which ginsenoside Re protects from myocardial injury induced by H/R. HL-1 cells derived from AT-1 mouse atrial cardiomyocyte tumor line were divided into control, H/R, and H/R + ginsenoside Re groups. Cell viability was measured by CCK-8 assay. ATP levels were quantified by enzymatic assays. Signaling pathway was predicted by network pharmacology analyses and verified by luciferase assay and gene-silencing experiment. The relationship between ginsenoside Re and its target genes and proteins was analyzed by docking experiments, allosteric site analysis, real-time PCR, and ubiquitination and immunoprecipitation assays. Our results showed that ginsenoside Re treatment consistently increased HL-1 cell viability and significantly up-regulated ATP levels after H/R-induced injury. Network pharmacology analysis suggested that the effect of ginsenoside Re was associated with the regulation of the Hypoxia-inducing factor 1 (HIF-1) signaling pathway. Silencing of HIF-1α abrogated the effect of ginsenoside Re on HL-1 cell viability, which was restored by transfection with an HIF-1α-expressing plasmid. Results of the bioinformatics analysis suggested that ginsenoside Re docked at the binding interface between HIF-1α and the von Hippel-Lindau (VHL) E3 ubiquitin ligase, preventing VHL from binding HIF-1α, thereby inhibiting the ubiquitination of HIF-1α. To validate the results of the bioinformatics analysis, real-time PCR, ubiquitination and immunoprecipitation assays were performed. Compared with the mRNA expression levels of the H/R group, ginsenoside Re did not change expression of HIF-1α mRNA, while protein level of HIF-1α increased and that of HIF-1α[Ub]n decreased following ginsenoside Re treatment. Immunoprecipitation results showed that the amount of HIF-1α bound to VHL substantially decreased following ginsenoside Re treatment. In addition, ginsenoside Re treatment increased the expression of GLUT1 (glucose transporter 1) and REDD1 (regulated in development and DNA damage response 1), which are targets of HIF-1α and are critical for cell metabolism and viability. These results suggested that Ginsenoside Re treatment attenuated the myocardial injury induced by H/R, and the possible mechanism was associated with the inhibition of HIF-1α ubiquitination.

Fouling is widely recognized as a main barrier to the sustainable development of membrane separation technologies. This study demonstrated a hierarchically textured superhydrophilic membrane, which was fabricated via nanocasting and post-fabrication grafting of surface-tailored silica nanoparticles. Nanocasting, using a prepared polydimethylsiloxane plate as an intermediate transfer template, gave rise to a micro-scaled surface texture resembling the surface pattern of a stainless-steel mesh. The resultant textured membrane surface was then sequentially grafted with poly(methacrylic acid) and surface-tailored silica nanoparticles through plasma induced graft copolymerization and self-assembly dip-coating, respectively, thereby resulting in an extra nano-scaled nanoparticle layer. The appropriate hierarchical structure and high surface energy of the membrane surface enormously improved its affinity with water, thus rendering the resultant functionalized membrane (designated as textured_F) superhydrophilic (water contact angle instantly reduced to 0° upon contact). Compared with a commercial 0.22 μm membrane, the textured_F membrane exhibited a slightly higher permeability and a significantly improved rejection ability, probably owing to the dense silica nanoparticle layer which functioned as a selective barrier. Moreover, in the systematic multi-cycle filtration experiments with a practical membrane bioreactor supernatant, the textured_F membrane exhibited a ∼2.4 times higher cleaning efficiency than the commercial membrane, demonstrating a dramatically improved antifouling capability. This improvement was probably due to the superhydrophilic and hierarchical membrane surface, which potentially facilitated the formation of an in situ hydration layer and peripheral turbulent flow thus resisting the adhesion of foulants.

Foulant hydrophobicity has been regarded as a key factor in membrane fouling. While hydrophobic/philic fractionation using DAX (or XAD) resin column has been extensively utilized in fouling studies, the critical retention factor (k’cr, the ratio of water volume to column volume) has been long neglected which can alter the definition and relative degree of “hydrophobicity” of the obtained fractions and affect fouling results. To this end, this study compared fouling behavior of a membrane bioreactor (MBR) supernatant fractionated at varied k’cr, and found that not the distinctively strong “hydrophobic” (k’cr > 50) or “hydrophilic” (k’cr

A novel nickel(ii) complex, [Ni(2,2'-bpy)3](H2SBTC)(H2O)5 (1) (2,2'-bpy = 2,2'-bipyridyl), was synthesized based on [Ni(2,2'-bpy)3]2+ discrete units and a partially deprotonated sulfonate-carboxylate ligand of H4SBTC (5-sulfonyl-1,2,4-benzentricarboxylic acid). The adjacent [Ni(2,2'-bpy)3]2+ cationic units were connected to H2SBTC2- anions by hydrogen bonds to form a one-dimensional (1-D) chain. The 1-D chains were further linked using hydrogen bonds from free water molecules and H2SBTC2- anions to generate a two-dimensional (2-D) plane structure. The proton conductivity of 1 reaches 1.3 × 10-4 S cm-1 at 318 K, 98% RH. Furthermore, hybrid membranes composed of polyvinyl alcohol (PVA) and 1 as fillers were prepared with different mass percentages. The proton conductivity of 1@PVA-5 was found to be 1.6 × 10-3 S cm-1 at 313 K and 98% RH. The large number of alcoholic hydroxyl groups in PVA promote the resulting conductivity.

The Zn(II) MOF with a tripyridinium-based hexacarboxylate shows direct color change on exposure to small primary amines and UV-assisted color response on exposure to small alcohols. The reversible, group-specific and size-selective chemochromic/chemophotochromic behaviours are ascribed to spontaneous/photoinduced guest-to-host electron transfer within the unique confined space furnished with electron-deficient sites.

OBJECITVIE To compare the liver protective activity of fresh/dried dandelion extracts against acetaminophen (APAP)-induced hepatotoxicity. METHODS Totally 90 Kunming mice were randomly divided into 10 groups according to body weight (9 mice for each group). The mice in the normal control and model (vehicle control) groups were administered sodium carboxymethyl cellulose (CMC-Na, 0.5%) only. Administration groups were pretreated with high and low-dose dry dandelion extract (1,000 or 500 g fresh herb dried and then decocted into 120 mL solution, DDE-H and DDE-L); low-, medium- and high-dose dandelion juice (250, 500, 1,000 g/120 mL, DJ-L, DJ-M, and DJ-H); fresh dandelions evaporation juice water (120 mL, DEJW); dry dandelion extract dissolved by pure water (1 kg/120 mL, DDED-PW); dry dandelion extract dissolved by DEJW (120 g/120 mL, DDED-DEJW) by oral gavage for 7 days at the dosage of 0.5 mL solution/10 g body weight; after that, except normal control group, all other groups were intraperitonealy injected with 350 mg/kg APAP to induce liver injury. Twenty hours after APAP administration, serum and liver tissue were collected and serum alanine aminotransferase (AST), aspartate transaminase (ALT), alkaline phosphatase (AKP), malondialdehyde (MDA), glutathione (GSH), superoxide dismutase (SOD) activities were quantified by biochemical kits; tumor necrosis factor (TNF-α), interleukin (IL)-2, and IL-1 β contents in liver tissue were determined by enzyme linked immunosorbent assay kits. Histopathological changes in liver tissues were observed by hematoxylin and eosin staining; TUNEL Assay and Hoechst 33258 staining were applied for cell apoptosis evaluation. The expressions of heme oxygenase-1 (HO-1), nuclear factor erythroid-2-related factor 2 (Nrf-2), caspase-9, B-cell leukemia/lymphoma 2 (Bcl-2), Bax and p-JNK were determined by Western blot analysis. RESULTS Pretreatment with fresh dandelion juice (FDJ, including DJ-L, DJ-M, DJ-H, DEJW and DDED-DEJW) significantly decreased the levels of serum ALT, AST, AKP, TNF-α and IL-1β compared with vehicle control group (P

Two new lanthanide complexes of nitronyl nitroxide radical have been synthesized and characterized on the structure, magnetism and fluorescence: [Ln(hfac)3(NITPh-(OCH3)2)2](Ln = (Tb(1),Dy(2)), (NITPh-(OCH3)2 = 2-(3′,4′-dimethoxy-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide); hfac = hexafluoroacetylacetonate). Two complexes crystallize in monoclinic space group C2/c, which have similar mononuclear structures. The central metal ion is eight coordinated by six oxygen atoms from three hfac molecules and two oxygen atoms from two nitronyl nitroxide radicals. The varying temperature magnetic susceptibility indicates that there are weak antiferromagnetic interaction between metal ions and nitronyl nitroxide radicals in complexes 1 (zJ′ = −0.145 cm−1) and 2 (zJ′ = −0.140 cm−1). Ac magnetic susceptibility studies exhibit no single-molecule magnet behavior in complexes 1 and 2. In addition, the fluorescence properties of 1 show that it is an excellent fluorescent probe of recognizing Cr2O72− anion. Because of the linear relationship at low concentration and detection limit reached 1 × 10−7 M, it can be used as a luminescence-based sensor for quantitative analysis.

The further advance of membrane distillation (MD) is hampered due to inadequate membrane durability challenged by wetting-induced performance deterioration. The current study presents a novel approach to fabrication of superhydrophobic polyvinylidene fluoride (PVDF) membranes via construction of hierarchical textures on membrane surfaces based on a nanocasting strategy. Two types of PVDF membranes with different surface textures were prepared, separately using a stainless-steel mesh (SSM) or its negative polydimethylsiloxane (PDMS) template as a fabrication substrate. The obtained membranes were systematically characterized in terms of membrane morphology, wetting behavior, MD performance, and antifouling performance. Consequently, the PDMS-based membrane obtained a plaited surface texture, resulting in a high static contact angle of ~153° and a high sliding angle of >90°. The resultant parahydrophobic membrane surface resembled a petal surface. The SSM-based membrane obtained a wave-like pattern, resulting in a high static contact angle of ~164° and a low sliding angle of ~6.8°. The resultant superhydrophobic membrane surface resembled a lotus leave surface. Moreover, both membranes achieved higher water flux and enhanced antifouling performance with no significant compromise in salt rejection. Particularly, the SSM-based membrane achieved the highest flux and best antifouling performance, suggesting promising applications in various fields.

This study systematically investigated the correlations between fluorescence distributions characterized by the excitation-emission matrix (EEM) and hydrophobic/hydrophilic composition of dissolved organic matter (DOM) in membrane bioreactors (MBRs). On the basis of samples from 10 full-scale MBRs, we performed point-to-point comparisons among different components using an EEM fluorescence quotient (FQ) method and obtained a hydrophobic/hydrophilic fluorophore distribution map via Wilcoxon signed rank test. Hydrophobic acids/bases (HOA/HOB) concentrated in the low-wavelength region [excitation wavelength (Ex) 235 nm [especially with emission wavelength (Em) = 300-360 nm]. Quantitatively, EEM regional contribution to whole wavelength fluorescence was found to significantly correlate with the hydrophobic/hydrophilic proportions of DOM, with Pearson's coefficients of 0.94 and 0.78 ( p < 0.01) for HOA and HIS, respectively. We established a linear regression model showing the HOA proportion as a function of the EEM regional contribution at (Ex, Em) = (200-285, 340-465 nm), with R2 = 0.876, which was validated via leave-one-out cross-validation and Monte Carlo simulation. This study shows a statistically hydrophobicity-dependent fluorescence property across different MBRs, and it might be applied to provide a quick estimation of hydrophobic/hydrophilic composition of DOM in wastewater treatment systems based on EEM monitoring.

A hydrophilic membrane commonly performs better in resisting fouling. But most prevailing polymeric membrane materials are hydrophobic thus prone to be fouled in practical operations. The current study presents a facile strategy for the fabrication of superhydrophilic polyvinylidene fluoride (PVDF) ultrafiltration membranes on the basis of a blending method and a dip-coating technique. A carboxyl-rich substance was firstly blended as an additive in the PVDF membrane matrix during fabrication. The incorporated carboxyl groups acted as anchor sites for the subsequent binding of amine-grafted silica nanoparticles (NPs). After a simple dip-coating operation, the PVDF membrane would be covalently functionalized to be superhydrophilic. Three types of carboxyl-rich additives including poly(methacrylic acid sodium salt), sodium alginate, and ethylenediaminetetraacetic acid (EDTA) were separately used to prepare different primary membranes for respective functionalization operations. The resultant membranes were systematically characterized in terms of hydrophilicity, morphology, permeability, and antifouling performance. Consequently, the simple dip-coating functionalization dramatically enhanced the surface hydrophilicity of all the additive-blended PVDF membranes. All the functionalized membranes obtained a significantly lower initial contact angle, which instantly reduced to

Four new rare-earth nitronyl nitroxide radical complexes, [Ln(hfac)3(NITPh-Pa)2][0.5CH3(CH2)5CH3] (Ln = Gd(1), Tb(2), Dy(3), Ho(4), hfac = hexafluoroacetylacetonate, NITPh-Pa = 2-(3′,4′-dioxylmethylene-phenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), have been synthesized. The X-ray crystal structure analysis revealed that four compounds have similar mononuclear tri-spin structures, in which the Ln(III) ions are eight-coordinated by two nitronyl nitroxide radicals and three hexafluoroacetylacetonate ligands to form a slightly distorted dodecahedron. In complexes 1–4, isolated mononuclear molecules connect each other through intermolecular hydrogen bonds to form 3D supermolecular framework. Magnetic investigation indicates there are ferromagnetic interactions between Gd(III) ions and radicals in complex 1. Alternating current(ac) magnetic susceptibilities of complexes 2 and 3 show that there are no non-zero out-of-phase signal, which indicates the inexistence of slow magnetic relaxation. The luminescence properties of complex 2 exhibit the characteristic emission peaks of Tb3+ ions and the potential for recognition of Cr2O72− and Cr3+ ions. Furthermore, nearly linear at low concentration and the low detection limit (0.01 μM) indicate that complex 2 may potentially be acted as luminescence-based sensor for quantitative and highly sensitive detection of Cr2O72− ion.

The use of homogeneous and polluting halides as nucleophilic cocatalysts lowers the economy and benignity of the CO2-epoxide cycloaddition over heterogeneous Lewis-acid catalysts like metal-organic frameworks (MOFs). Creating net positive charge at frameworks is a reasonable strategy to heterogenize halide anions within MOFs, but it is still challenging to achieve high halide loading while keeping adequate porosity. In this article, we report a facile approach to ionic MOFs with high halide content and improved catalytic activity. The catalysts were prepared by reacting azide-tagged MIL-101 with alkyne-tagged organic bromide salts. The efficient azide–alkyne click reaction within the mesoporous MOF allows quantitative cationization of the linkers, and the resultant bifunctional ionic MOFs contain one halide ion per metal center to the benefit of the cooperative catalysis. Catalytic studies suggest that the effects of varying the cationic groups and halide anions in the confined ionic space are different from those observed for homogeneous organic halides. The highest catalytic activity was demonstrated for the MOF having the smallest cationic group (quaternized trimethyl ammonium) and the intermediately nucleophilic halide (Br−). The catalyst also outperforms the ionic MOF catalysts reported prior to this work.

Coating@fabrics with self-healing hydrophobic properties for oil/water separation have attracted significant attention. However, currently used self-healing coating@fabrics only enable the recovery of surface properties of the coating on fabrics. If the coating gets seriously damaged from the interior (i.e., torn apart), the recovery of the oil/water separation performance becomes difficult. In this study, a novel strategy to achieve a self-healing ability based on coating materials with reversible dynamic bonds was proposed. To develop this idea, a self-healing silicon elastomer cross-linked via cobalt (Co)-based coordination was coated on polyethylene terephthalate (PET) fabrics. The as-modified fabrics exhibited hydrophobic properties with a contact angle (CA) of >140°, a high oil/water separation factor of around 99%, high durability (even at extremely low temperatures), and an ultra-fast self-healing ability at room temperature. After being immersed in liquid nitrogen and damaged under beating, the modified fabrics still exhibited fast self-healing properties (healing time was just 10 min) and a high oil/water separation efficiency of above 98%. Thus, this study proposes a novel design concept for the fabrication of coating@fabrics with outstanding self-healing efficiency to recover oil/water separation performance at room temperature, and may pave a way for the development of an efficient family of self-healing fabrics.

Considering the reliable characteristics and the suitable silica alumina content of kaolin, a new way of synthesizing a ZSM-5/NaA hybrid zeolite membrane on 170 mm length ceramic tubes by employing kaolin as a modification layer using a hydrothermal synthesis process was presented for the first time in this work. Kaolin was filtrated on the surface of the support (not only the ceramic tube, but also the NaA membrane layer) as a modification layer not only promoting the interface interlinkage among the support, NaA membrane and ZSM-5 membrane layer, but also promoting the growth of zeolite membranes. The SEM and XRD results showed that compact and homogeneous NaA and ZSM-5 zeolite layers were both formed with the thicknesses being 7.06 μm and 6.14 μm, respectively, after modification with kaolin. The permeation separation experiments demonstrated that the performance of the ZSM-5/NaA hybrid membrane was better than that of the monolayer zeolite membrane with permselectivities of H2 over CO2, N2, CO and CH4 of 5.40, 4.65, 4.70 and 3.93, respectively, which were higher than the corresponding Knudsen diffusion coefficients. Above all, modifying the support with kaolin and then synthesizing the ZSM-5/NaA hybrid membrane could strengthen the performance of the zeolite membrane effectively, which provided a new approach for the synthesis of high performance zeolite membranes in the field of membrane separation.

Recently, considerable attention has been paid to European eggs that were found to contain the poisonous insecticide fipronil. Excessive consumption of fipronil can harm the human body, in particular, the liver, thyroid, nervous system and kidneys. As a consequence, there is an urgent need to develop a method to detect fipronil. In this work, a lanthanide coordination polymer [Eu(SIP)(H2O)4]n (1) (NaH2SIP = 5-sulfoisophthalic acid monosodium salt) was synthesized and characterized by single-crystal X-ray crystallography, elemental analysis, infrared spectrum and powder X-ray diffractions. The X-ray studies show that 1 is a two-dimensional layered structure, which is constructed of fused {[Eu(H2O)4]3(SIP)3} pseudo-hexagonal grids. The luminescence properties of 1 exhibit effective recognition for fipronil in methanol solution. Furthermore, a wide linear range (10-6-10-4 M), a low detection limit of 0.8 μM, high selectivity and excellent recyclability, reveal that 1 can potentially act as a luminescence-based sensor for quantitative and highly sensitive detection of fipronil. To the best of our knowledge, it is the first time that a metal-organic coordination polymer, as a fluorescent-based probe, has been used for the detection of fipronil. Moreover, fluorescent-based test papers of 1 have also been prepared, which can be regarded as a simple and practical method for detecting fipronil.

A new metal–organic framework (MOF), [{(H3O)[Eu (SBDB)(H2O)2]}n] (H4SBDB = 1,5-disulfo-benzene-2,4-dicarboxylic acid) (1), was successfully synthesized under solvothermal conditions. Ten central Eu3+ ions are coordinated by the H4SBDB ligands and two coordination water molecules. The adjacent Eu3+ ions are connected by oxygen atoms from carboxyl groups, forming a 1D chain. 1D chains are linked by H4SBDB ligands to induce a 2D infinitely extensible planar structure, and then connected by hydrogen bonds to form a 3D supernetwork structure. Complex 1 exhibits excellent thermal and chemical stability. AC impedance analysis shows that the highest proton conductivity of 1 reaches up to 1.0 × 10−4 S cm−1 (338 K, 98% RH). Furthermore, complex 1 is an excellent luminescence-based sensor with high sensitivity and a low detection limit for ascorbic acid (AA) in aqueous solutions.

A microporous europium metal–organic framework (Eu-MOF), namely, {[Eu3(bpydb)3(HCOO)(OH)2(DMF)]·3DMF·2H2O}n (1) with asymmetric trinuclear metal clusters extended by 4,4′-(4,4′-bipyridine-2,6-diyl) dibenzoic acid has been synthesized via the solvothermal method. PXRD of 1 confirms that it possesses excellent water stability and pH stability. The photo-luminescence properties of 1 exhibit effective recognition of Cr2O72−, MnO4−, and Cr3+ ions and SDBS. Furthermore, a wide linear range, high quenching constant and a low detection limit reveal that 1 can potentially act as a luminescence-based sensor for quantitative and highly sensitive detection of Cr2O72−, MnO4−, and Cr3+ ions as well as SDBS in aqueous solutions. To the best of our knowledge, the detection limit of 1 is the lowest value reported for Ln-MOF-based luminescent sensors to detect Cr2O72− ions (0.5 μM) in aqueous solutions. The use of a rare earth fluorescent probe for detecting MnO4− ions is not common. It is the first time that Ln-MOF as a fluorescence probe is used for detecting SDBS. Moreover, fluorescent-based test papers of 1 have also been prepared, which can be helpful to develop visual detection for Cr2O72−, MnO4−, and Cr3+ ions as well as SDBS in daily applications.

Two novel lanthanide–organic frameworks, {[Ln3(bpydb)3(HCOO)(OH)2(DMF)]·3DMF·xH2O}n (Ln = Eu3+ (1) and x = 2; Tb3+ (2) and x = 1; bpydbH2 is 4,4′-(4,4′-bipyridine-2,6-diyl) dibenzoic acid; DMF denotes N,N′-dimethylformamide), have been synthesized and structurally characterized. Topological analysis reveals that 1 and 2 are 12-connected frameworks with an fcu topology, which are based on rod-shaped {Ln6} as 12-connected nodes. AC impedance analysis shows that the proton conductivity of 1 and 2 reaches up to 1.7 × 10−4 S cm−1 at 325 K and 1.1 × 10−4 S cm−1 at 334 K, respectively, under 98% RH. Furthermore, the polymer composite membranes of poly(vinyl alcohol) (PVA) and 1 or 2 as fillers with different mass percentages (X%, with the composite membrane denoted as 1@PVA-X or 2@PVA-X) were fabricated. The proton conductivities of both 1@PVA-10 and 2@PVA-10 are higher than those of 1 and 2 under the same conditions, which can be interpreted that the PVA polymer can provide a continuous proton transfer pathway for 1 and 2. To the best of our knowledge, it is the first composite based on Ln–MOFs and a polymer as proton exchange membranes. This research may contribute to the further development of Ln–MOFs in the field of proton exchange membranes in fuel cells.

The potential of using excitation–emission matrix (EEM) fluorescence spectroscopy in revealing organic matter properties has yet to be fully exploited. A fluorescence quotient (FQ) method was established to graphically compare different EEM spectra and hence, reflect the differential properties of organic matter in a wastewater treatment process on the basis of EEM. FQ is defined as a standardized element-wise quotient of two EEM spectra for organic matter in different states (e.g. before and after degradation) or in different forms (e.g. in sludge, in supernatant or on membranes as foulants). This method was applied to two full-scale membrane bioreactors, with multiple FQs calculated among the influent organics, sludge supernatant organics, extracellular polymeric substances and membrane foulants. Statistical analyses confirmed that the distribution of FQ as a function of the fluorescence excitation and emission wavelengths was significantly meaningful in highlighting the differential EEM characteristics, which enabled a clear depiction of the active regions of the different organics on an excitation–emission map. This might therefore indicate the differential propensity for a specific behavior of organic matter (such as biotransformation, sludge/water-phase distribution and membrane fouling) from the perspective of EEM. The FQ method provides a potential tool for EEM data exploitation to reflect organic matter behavior in wastewater treatment processes.

Exploring highly effcient bifunctional oxygen catalysts is a central issue for rechargeable Zn–air batteries. Herein, bimetallic cobalt/iron nitrides in situ embedded into nitrogen, sulfur-codoped carbon nanotubes (CoN/FeN@N,S-C-800) was firstly developed by pyrolysis of a Fe-glucosamine coated tetrazole energetic metal − organic framework. Due to the significant nitrogen (5.38at%) dopant content, the synergistic effect between bimetallic nitrides, and interconnected N, S-codoped carbon nanotubes, the as-prepared CoN/FeN@N,S-C-800 exhibits an ultra-high half-wave potential (0.865 V) for oxygen reduction reaction (ORR) and a low overpotential (385 mV) for oxygen evolution reaction (OER). The assembled liquid Zn–air battery affords a high peak power density of 168.3 mW cm−2 and a low voltage gap of 0.55 V after 600 cycles (100 h). Impressively, an all-solid-state ZAB catalyzed by CoN/FeN@N,S-C-800 affords a high OCV of 1.354 V, and three all-solid-state ZABs in series can successfully light LED (~2.2 V), displaying tremendous potentials in portable devices.

Currently, the degradation of polyamide (PA) layers in thin-film composite (TFC) membranes due to chlorine-based chemical cleaning is still the major obstacles to the development of reverse and forward osmosis (FO) technologies. In this study, layered double hydroxide (LDH) nanoparticles were bound on the TFC membranes by virtue of a polydopamine (PDA)-induced immobilization process to enhance its chlorine and fouling resistance. Two modification strategies as deposition and dip-coating were compared. The accelerated chlorination experiments using 1000 ppm NaOCl indicated the excellent chlorine-resistant performance of the deposition-modified TFC membrane, the chlorine-resistant time was improved about 96 times than the control membrane. The LDH layer served as a barrier to protect the PA layer from chlorination. Moreover, the LDH-modified membrane exhibited a better resistance to organic fouling. Also, the bound LDH layer succeeded to reduce the attachment of bacteria, indicating a promising anti-fouling capability. In general, the modification using the LDH nanoparticles effectively improved the chlorine and fouling resistance of the TFC membranes, suggesting promising applications in various areas.

We report our observations of the transient formation of the translational and rotational defects in the host lattice of methane hydrates. We perform molecular dynamics simulations of a fully occupied methane hydrate system and find that the hydrogen bonds of a water molecule can be thermally broken, and the water molecule can then rotate more freely. We observe the formation of transient Bjerrum defects around the water molecule, and the two hydrogens of the water molecule can be interchanged when the transient defects anneal. The 95% confidence interval for the rate of the hydrogen interchange is estimated to be 1.3 × 105–2.4 × 105 s–1 per water molecule, and the 95% confidence interval for the associated free energy of activation is estimated to be 38.2–39.4 kJ/mol at 270 K. We also observe the transient formation of vacancy-interstitial water defects. The formation and annealing of these vacancy-interstitial defects can result in the interchange of two or three neighboring water molecules on the gas h...

A simple and mild Mn(OAc)3-promoted oxidative coupling of 1,4-dimethoxybenzenes with sodium and lithium sulfinates was developed. The reaction proceeded readily at room temperature in air, and various sulfones were synthesized in moderate to high yields. In addition, a straightforward approach for the conversion of organolithium reagents and sulfur dioxide into sulfonylated 1,4-dimethoxybenzenes was explored.

A new kind of N-containing heterocyclic borate ester (MTMDB) as lubricant additive was synthesized and characterized. The tribological behaviors of MTMDB and ZDDP in 100N base oil were evaluated through four-ball machine. The surface morphology of the worn surface lubricated by MTMDB was investigated by scanning electron microscope (SEM) and the tribological mechanisms were analyzed by energy dispersive spectrometer (EDS). The results show that the synthesized additive exhibits high hydrolytic stability, good anti-wear property and excellent extreme pressure performance. When 2.5% MTMDB was added into the 100N base oil, the smallest wear scar diameter (WSD) 0.48 mm is obtained. Furthermore, S and B elements were detected on the surface of the abraded steel. This can be confirmed that MTMDB has adsorbed and reacted with the steel surface during the rubbing process and generates a protective film.

Based on the nitroxide radicals, four-spin complexes [Mn(hfac)2(IMpPhCl)]2·NITpPhCl (1) and [Mn(hfac)2(IMmPhCl)]2·NITmPhCl (2) (IMpPhCl = 2-(4'-chlorophenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl, IMmPhCl = 2-(3'-chlorophenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl, hfac = hexafluoroacetylacetonate) have been synthesized and characterized by single-crystal X-ray diffraction. The X-ray crystal structure analyses show that the structures of the two compounds are similar and the imino nitroxide radical ligand acts as a bridge ligand linking two Mn(II) ions through the oxygen atom of the N–O group to form a four-spin system. Two kinds of nitroxide radicals: nitronyl nitroxide and imino nitroxide radicals coexist in the cyclic Mn(II) complexes. The magnetic studies show that there exists an antiferromagnetic interaction between Mn(II) ions and the imino nitroxide radical ligands, which is explained by spin polarization mechanism. The antiferromagnetic interaction of Mn−Rad in complex 2 (J1 = −9.36 cm−1) is stronger than that in complex 1 (J1 = −9.19 cm−1), which is consistent with crystal structure of complexes (The bond length of the shortest Mn-O in complex 2 (2.1625 A) is smaller than complex 1 (2.1898 A)).

The membrane bioreactor (MBR) technology is a rising star for wastewater treatment. The pollutant elimination and membrane fouling performances of MBRs are essentially related to the dissolved organic matter (DOM) in the system. Three-dimensional excitation-emission matrix (3D-EEM) fluorescence spectroscopy, a powerful tool for the rapid and sensitive characterization of DOM, has been extensively applied in MBR studies; however, only a limited portion of the EEM fingerprinting information was utilized. This paper revisits the principles and methods of fluorescence EEM, and reviews the recent progress in applying EEM to characterize DOM in MBR studies. We systematically introduced the information extracted from EEM by considering the fluorescence peak location/ intensity, wavelength regional distribution, and spectral deconvolution (giving fluorescent component loadings/scores), and discussed how to use the information to interpret the chemical compositions, physiochemical properties, biological activities, membrane retention/fouling behaviors, and migration/ transformation fates of DOM in MBR systems. In addition to conventional EEM indicators, novel fluorescent parameters are summarized for potential use, including quantum yield, Stokes shift, excited energy state, and fluorescence lifetime. The current limitations of EEM-based DOM characterization are also discussed, with possible measures proposed to improve applications in MBR monitoring.

Introduction: Ulcerative colitis (UC) is an inflammatory bowel disease with a high incidence rate and a difficult treatment regimen. Recently, significant advances in the treatment of intestinal diseases, particularly UC, have been made with the use of the drugs baicalin and baicalein, separately or in combination. However, the therapeutic efficacy and mechanism of action of baicalin, baicalein, and their combination therapy, in the treatment of UC has not been fully elucidated. Materials and Methods: we constructed a UC rat model that encompassed a variety of complex factors, including a high-sugar and high-fat diet, a high temperature and humidity environment (HTHE), excess drinking, and infection of Escherichia coli. Model rats were then treated with baicalin, baicalein, or a combination of the two. Results: The results showed significant differences in the therapeutic effects of baicalin, baicalein, and the combination therapy, in the treatment of UC, as well as differences in the inhibition of inflammation via the nuclear factor-κB and MAPK pathways. The rat model of UC was established as described above. Then, the rats were treated for 7 days with baicalin (100 mg kg-1), baicalein (100 mg kg-1), or both (100 mg kg-1, baicalin: baicalein = 4:1/1:1). Clinical symptoms and signs, body temperature, organ indices, histopathology, blood biochemistry, and metabolites were examined to compare treatment effects and indicators of UC. Baicalin, YSR (Young Scutellaria baicalensis ratio of baicalin and baicalein), baicalein, and WSR (Withered Scutellaria baicalensis ratio of baicalin and baicalein) had significantly different effects in terms of clinical symptoms and signs, body temperature, organ indices, serum inflammatory cytokine levels, blood biochemistry, and histopathology changes in the main organs; YSR exhibited the best treatment effects. LC-MS/MS was used to detect the conversion of baicalin, baicalein, or both, into the six types of metabolites: baicalin, wogonoside, oroxin A, baicalein, wogonin, and oroxylin A. The levels of the six metabolites under the different treatment conditions were significantly different in the large intestine, small intestine, and lungs, but not in the blood. The levels of the six metabolites were significantly different in the large intestine, small intestine, and lung, but not in the serum. Conclusion: All these results indicate that baicalin and baicalein should be used more accurately in specific diseases, especially baicalin or high content of baicalin in Scutellaria baicalensis (Tiaoqin) should be preferred in treatment of UC.

Low molecular weight, highly crosslinked silicone resins are widely used as reinforcing agents for highly transparent elastomers and adhesion/tack promoters in gels. The resins are complex mixtures and their structure / property relationships are ill defined. We report the synthesis of a library of 2, 3 and 4-fold hyperbranched polymeric oils that are comprised of linear, lightly branched or highly branched dendronic structures. Rheological examination of the fluids and tack measurements of gels filled with 10, 25 or 50% dendronic oils were made. Viscosity of the hyperbranched oils themselves was related to molecular weight, but more significantly to branch density. The properties are driven by chain entanglement. When cured into a silicone gel, less densely branched materials were more effective in improving tack than either linear oils or Me3SiO-rich, very highly branched oils of comparable molecular weight, because the latter oils underwent phase separation.

Objectives Cardiac Ca2+ signalling plays an essential role in regulating excitation‐contraction coupling and cardiac remodelling. However, the response of cardiomyocytes to simulated microgravity and hypergravity and the effects on Ca2+ signalling remain unknown. Here, we elucidate the mechanisms underlying the proliferation and remodelling of HL‐1 cardiomyocytes subjected to rotation‐simulated microgravity and 4G hypergravity. Materials and Methods The cardiomyocyte cell line HL‐1 was used in this study. A clinostat and centrifuge were used to study the effects of microgravity and hypergravity, respectively, on cells. Calcium signalling was detected with laser scanning confocal microscopy. Protein and mRNA levels were detected by Western blotting and real‐time PCR, respectively. Wheat germ agglutinin (WGA) staining was used to analyse cell size. Results Our data showed that spontaneous calcium oscillations and cytosolic calcium concentration are both increased in HL‐1 cells after simulated microgravity and 4G hypergravity. Increased cytosolic calcium leads to activation of calmodulin‐dependent protein kinase II/histone deacetylase 4 (CaMKII/HDAC4) signalling and upregulation of the foetal genes ANP and BNP, indicating cardiac remodelling. WGA staining indicated that cell size was decreased following rotation‐simulated microgravity and increased following 4G hypergravity. Moreover, HL‐1 cell proliferation was increased significantly under hypergravity but not rotation‐simulated microgravity. Conclusions Our study demonstrates for the first time that Ca2+/CaMKII/HDAC4 signalling plays a pivotal role in myocardial remodelling under rotation‐simulated microgravity and hypergravity.