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In this work, novel antibacterial cellulose diacetate/poly(ethylenimine)/hyaluronic acid (CDA/PEI/HA) composite three-dimension (3D) scaffolds were prepared through electrospinning and post-processing. Firstly, CDA/PEI 2D composite nanofiber membranes were prepared by electrospinning, and then the CDA/PEI/HA 3D composite scaffolds were fabricated by post-processing and freeze-drying of CDA/PEI membranes. In particular, HA was added to improve the biocompatibility of composite scaffolds. Compared with CDA/PEI scaffolds, CDA/PEI/HA composite scaffolds showed higher water absorbing rate, higher water retention rate and higher mechanical strength. Moreover, CDA/PEI/HA composite scaffolds with abundant positive charge were benefit for improving antibacterial activity. CDA/PEI/HA scaffolds with biology function of HA were benefit for improving hemocompatibility and cell proliferation of CDA/PEI scaffolds. In summary, antibacterial CDA/PEI/HA scaffolds could protect wound from bacterial infection, improve cellular behavior and accelerate wound healing. Thus, CDA/PEI/HA scaffolds could be potential application for wound dressing.

Temperature-responsive resistance transition behaviors of the melamine sponges wrapped with different graphene oxide derivatives (i.e. nanoribbon, wide-ribbon and sheet) were investigated. Melamine sponge composites coated by three types of GO derivatives were prepared by a simple dip-coating approach. All these composites show good mechanical flexibility and reliability (almost unchanged compressive stress at 70 % strain after 100 cycles), high hydrophobicity (water contact angle >120°), excellent flame resistance (self-extinguishing) and structural stability even after burning, which was used to construct the resistance-based fire alarm/warning sensor. Notably, the different resistance response behaviors of such sensors are strongly dependent on the GO size and network formed on the MF skeleton surface. Typically, at a fixed high temperature of ∼350 ℃, the three fire alarm sensors show different response time (to trigger the alarm light) of 6.3, 8.4 and 11.1 s for nanoribbon, wide-ribbon and sheet at the same concentration, respectively. The structural observation and chemical analysis demonstrated that the discrepancy of temperature-responsive resistance transition behaviors of various GO derivatives was strongly determined by their different thermal reduction degrees during the high-temperature or flame treating process. This work offers a design and development for construction of smart fire alarm device for potential fire prevention and safety applications.

Multifunctional nanodevices have shown great promise as robust tools in cancer theranostics. Carbon nanohorns (CNHs) of large specific surface area, low toxicity and unique physicochemical properties are among one of ideal platforms to fabricate the nanodevices. Herein, we develop a water-dispersible carbon nanohorn−polyglycerol−gold (CNH-PG-Au) nanohybrid through surface engineering of CNHs, which is further loaded with chemotherapeutic drug doxorubicin (DOX) to afford DOX@CNH-PG-Au nanodevice. Benefiting from the excellent hydrophilicity of PG, as-prepared multifunctional DOX@CNH-PG-Au possesses good aqueous dispersibility and colloidal stability enabling biomedical applications. DOX@CNH-PG-Au nanoparticles are taken up by 4T1 mouse breast cancer cells and mainly disperse in the lysosomes, where the mild acidic condition promotes the release of DOX. DOX@CNH-PG-Au induces more cell apoptosis under X-ray irradiation than DOX@CNH-PG of the same DOX concentrations, which is attributed to increased DNA damage by synergistic effect of DNA intercalation of DOX and radiosensitization of Au nanoparticles. Upon intravenous administration, DOX@CNH-PG-Au nanoparticles steadily accumulate in 4T1 tumor through enhanced permeability and retention (EPR) effect, and the tumor can be clearly observed by photoacoustic imaging. In vivo tumor treatment using DOX@CNH-PG-Au together with X-ray irradiation effectively inhibits tumor growth through radiochemotherapy. Our work demonstrates the great potential of DOX@CNH-PG-Au nanodevice in cancer theranostics.

Single-atom catalysis recently attracts great attentions, however, whether single atom or their nanoparticle (NP) has the advantage in its intrinsic activity remains under heated debate. Ag/Al2O3 is a widely used catalyst for many catalytic reactions, while the effect of Ag particle size on the activity is seldom investigated due to the great difficulty in synthesizing single atom Ag and Ag clusters/particles with different sizes. Herein, we firstly prepared an atomically dispersed Ag/Al2O3 catalyst using a nano-sized γ-Al2O3 as the support, subsequently obtained a series of Ag0/Al2O3 catalysts with different Ag particle sizes by H2 reducing single-atom Ag/Al2O3 catalyst at various temperatures. The Ag0/Al2O3 treated at 600 °C demonstrated superior CO oxidation performance over single-atom Ag/Al2O3 and the Ag/Al2O3 treated at 400 and 800 °C. Based on experimental data and density functional theory (DFT) calculation results, we reveal that the larger Ag0 particle is beneficial to oxygen activation and improves the valence stability during oxidation reaction, while the aggregation of Ag0 particle also accordingly decreases the concentration of surface active sites, hence, there is an optimum Ag0 particle size. Our findings clearly confirm that Ag0 nanoparticle has the advantage over single-atom Ag species in its intrinsic activity for CO oxidation.

Graphite carbon nitride (g-C3N4), a two-dimensional polymer semiconductor material, has good semiconductor properties, suitable electronic energy band structure, excellent physical and chemical stability. It is widely used in the field of energy and materials science such as photoelectric conversion. In this paper, the progress of g-C3N4 in dye sensitized solar cells (DSSC) and perovskite solar cells (PSC) was reviewed. As a new semiconductor material, g-C3N4 has the advantages of simple preparation, abundant amino and Lewis basic groups. Therefore, on the basis of excellent structure of g-C3N4, its electronic and optical properties are utilized to further expand its application in the field of photoelectric conversion.

Carbon nitride (CN) polymer is considered as a potential material for photocatalysis, but surfers from the low photoconversion efficiency due to its high defect density. Although the defects can be limited through the crystallization of CN, the photocatalytic activity of single-component photocatalyst is still restricted by the recombination of photoexcited carriers. In our work, the ordered Schottky heterojunction of heptazine-based crystalline carbon nitride (HCN) and Ti3C2 MXene was successfully prepared through ionothermal method. The HCN/Ti3C2 composites exhibit higher photocatalytic performance than pristine HCN. Particularly, the HCNT20 sample exhibits the highest photocatalytic H2 evolution activity, which is about 8 and 2 times higher than that of bulk CN and pristine HCN, respectively. The results of charge transfer dynamics and DFT calculation reveal that the photocatalytic enhancement mechanism is primarily attributed to the synergistic effects of crystallization of CN, excellent conductivity of Ti3C2 and well-constructed Schottky heterojunction.

Bronsted acid-catalyzed direct C(sp2)-H alkylation of N-heteroaromatics with cyclic ethers via a cross-dehydrogenative coupling reaction in the presence of benzoyl peroxide was developed. This methodology successfully provided an easy access to a variety of alkyl-substituted quinoxaline, benzoimidazole, pyrazine, pyrimidine, quinoline, isoquinoline, and pyridine derivatives in up to 94% yield under metal-free conditions.

Two rearranged triterpenoids, representing new subtypes of pentacyclic triterpenoids, with unique 6/6/6/7/5 and 6/6/5/6/6/6 ring systems were isolated from Alstonia scholaris. Their structures were established by spectroscopic analysis, single-crystal X-ray diffraction, and electronic circular dichroism calculations. Both compounds exhibited potent antihyperuricemic bioactivity in vitro and in vivo.

We report herein the asymmetric total synthesis of norzoanthamine using radical reactions as key steps for rapid access to the congested carbocyclic core, which is the major synthetic challenge for most zoanthamine alkaloids. (1) The Ueno-Stork radical cyclization was applied to construct the adjacent quaternary centers at the C-9 and C-22 positions; (2) a Co-catalyzed HAT radical reaction was successfully applied to construct the quaternary center at C-12 via Csp3 -Csp2 bond formation; (3) a Mn-catalyzed HAT radical reaction was used to stereospecifically reduce the tetra-substituted olefin (C13=C18) and install the contiguous stereocenters in proximity to the quaternary center. A one-pot bio-inspired cyclization step was finally applied to forge the unstable bis-amino acetal skeleton. Our approach can precisely control the stereochemistry of seven vicinal stereocenters and effectively construct the highly congested heptacyclic skeleton.

Chaenomeles speciosa (Sweet) Nakai is a dual-purpose Chinese herbal medicine and functional food favored by minorities in Southwest China, and its fruits are used for the treatment of dyspepsia, dysentery, enteritis, and rheumatism inflammation. Some diseases may be related to microbial infection; however, it is not known how the fruits possess antimicrobial activity. We evaluated the antimicrobial bioctivity of different evaluation extracts of C. speciosa fruits by in vitro and in vivo with colony-forming unit assays, and the strongest bioactive-guided fraction was selected for column chromatography (CC), UHPLC-QTOF-MS/MS, and NMR spectroscopy to confirm the chemical constituents. The most possible antimicrobial mechanism of C. speciosa fruits was explored by metabolomics approach, fluorescence microscopy imaging, and scanning electron microscopy (SEM). Thirty compounds, which were major characteristic ions of the bioactive fraction, were determined precisely. The bioactive fraction could inhibit 18 pathogenic microorganisms, significantly reduced, especially drug-resistant bacteria, compared to ampicillin sodium salt, fluconazole, and berberine chloride form; and the minimum inhibitory concentration (MIC) or minimum fungicidal concentration (MFC) values were in the range of 0.1-1 mg/mL. The compounds 2'-methoxyaucuparin (1) and oleanolic acid (20) not only have antibacterial activity but also may have synergistic effects. Further, the bioactive fraction might inhibit the biofilm formation, enhance immunity, and restore bacterial infection damage in vitro and in vivo to kill microorganisms. The data indicated that C. speciosa fruits' major bioactive fraction enriched with triterpenes, flavonoids, and phenolics could be developed as a functional supplement for individuals to prevent and treat microbial infection.

A series of triphenylamine (TPA) derivatives with various substituent groups were prepared and showed different absorption and fluorescence characteristics due to the substituent effect. On account of the existence of pyridine units, these TPA derivatives exhibited acid-induced tunable multicolor fluorescence emission including white light emission. In addition, acid-induced fluorescence regulation of these compounds has been also realized in the solid state, which enable them to be successfully constructed the stimuli-responsive fluorescent films and fluorescent inks for inkjet printing.

Context Capsule of alkaloids from the leaf of Alstonia scholaris (L.) R.Br. (Apocynaceae) (CALAS) is a new investigational botanical drug (No. 2011L01436) for bronchitis, post-infectious cough and asthma. Objective To observe the clinical safety and tolerability of CALAS. Materials and methods Subjects were assigned to eight cohorts, and each received randomly CALAS or placebo in one of single ascending dose (SAD) of 8, 40, 120, 240, 360, 480, or in one of multiple ascending dose (MAD) of 40 or 120 mg, three times daily for 7 days. Each cohort contained two placebo subjects. Results Sixty-two enrolled volunteers completed the study and no serious adverse events and clinically significant changes in vital signs, electrocardiography, and upper abdominal Doppler ultrasonography were observed. The ratios of treatment-emergent adverse events (TEAEs) were reported in 11/46 (23.91%) of CALAS groups and 3/16 (18.75%) of the placebo group (p > 0.05), respectively, based on the results of SAD and MAD. All TEAEs were mild, transient, and disappeared without any intervention. The TEAEs possibly related to CALAS treatment were as followings: hiccups (4/46: 8%), dry mouth and nausea (3/46: 6%), increased sleep (2/46: 4%), abdominal distension (1/46: 2%), bilirubin elevated (1/46: 2%). Discussion and conclusions CALAS is safe and well-tolerated with no unexpected or clinically relevant safety concerns up to a single dose of 360 mg and three times daily for 7 days up to 120 mg in healthy Chinese volunteers, supporting further Phase II studies.

The reaction conditions and scope of the excited-state Nazarov reaction of dicyclicvinyl ketones were studied. The stereochemistry of this electrocyclization is consistent with the mechanism of the pericyclic reaction and Woodward-Hoffmann rule. UV-light-promoted excited-state Nazarov reactions gave hydrofluorenones bearing a syn-cis configuration via a disrotatory cyclization. The core tricyclic hydrofluorenones of pyrrocidines and wortmannines were constructed via the excited-state Nazarov reactions, which demonstrated their synthetic potential in complex natural product total synthesis.

Two new asymmetric complexes with the chemical structural formulas [{Co2(L)(μ2-OH)}{Co2(L)(OAc)(CH3OH)}{Co2(L)(μ2-OCH3)}{Co2(L)(μ2-OAc)}]⋅4CH3OH and [Ni2(L)(μ2-OAc)(CH3OH)]⋅CH2Cl2⋅3CH3OH have been ...

Aggregation of antibodies, especially multimers, is a problem that puzzles scientific and industrial fields, and it is more serious in high concentration antibodies. We found that the high concentration antibody solution with rich multimers has a deeper color, which was confirmed by SEC–HPLC, DLS, and SEC–DLS methods. After that, the reasons for formation of multimers were analyzed. LC–MS was used for complete molecular weight analysis, which showed that the multimer sample could not be ionized, indicating a complex structure of multimers. ICP–MS was carried out to analyze the elements in the multimers, and revealed an important message that iron ion in the multimers was significantly higher. On further analysis of the interaction between iron ions and antibody molecules, the results showed that iron ions (Fe(III)) and antibody monomers irreversibly formed multimers under acidic conditions. This study provided useful insights for optimizing the development of antibody drug substances.

Hydrogel-based wearable devices have attracted tremendous interest due to their potential applications in electronic skins, soft robotics, and sensors. However, it is still a challenge for hydrogel-based wearable devices to be integrated with high conductivity, a self-healing ability, remoldability, self-adhesiveness, good mechanical strength and high stretchability, good biocompatibility, and stimulus-responsiveness. Herein, multifunctional conductive composite hydrogels were fabricated by a simple one-pot method based on poly(vinyl alcohol) (PVA), sodium alginate (SA), and tannic acid (TA) using borax as a cross-linker. The composite hydrogel network was built by borate ester bonds and hydrogen bonds. The obtained hydrogel exhibited pH- and sugar-responsiveness, high stretchability (780% strain), and fast self-healing performance with healing efficiency (HE) as high as 93.56% without any external stimulus. Additionally, the hydrogel displayed considerable conductive behavior and stable changes of resistance with high sensitivity (gauge factor (GF) = 15.98 at a strain of 780%). The hydrogel was further applied as a strain sensor for monitoring large and tiny human motions with durable stability. Significantly, the healed hydrogel also showed good sensing behavior. This work broadens the avenue for the design and preparation of biocompatible polymer-based hydrogels to promote the application of hydrogel sensors with comfortable wearing feel and high sensitivity.

The design and synthesis of low-cost and efficient bifunctional electrocatalysts for water splitting are critical and challenging. Hereby, a bimetallic phosphide embedded in a N and P co-doped porous carbon (FeCoP2@NPPC) material was synthesized by using sustainable biomass-derived N- and P-containing carbohydrates and non-noble metal salts as precursors. The obtained material exhibits good catalytic activities in hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and overall water splitting. The bimetallic alloy phosphide (FeCoP2) is the active site for electrocatalysis. Theoretical calculation indicates that the sub-layer Fe atoms and top-layer Co atoms in FeCoP2 exhibit a synergistic effect for enhanced electrocatalytic performance. The carbon matrix around the FeCoP2 can prevent the corrosion during the catalytic reactions. The hierarchically porous structure of the FeCoP2@NPPC material can promote the transfer of electrons and electrolyte, and increase the contact area of the active sites and electrolytes. N- and P-containing functionalities improve the wetting and conductivity properties of the porous carbon. Due to the synergistic effects, FeCoP2@NPPC requires a low overpotential of 114 and 150 mV at the current density of 10 mA cm-2 for HER in 0.5 M H2SO4 and 1.0 M KOH, and an overpotential of 236 mV for OER in 1.0 M KOH solution, which are much lower than those of FeP@NPPC and CoP@NPPC. Based on the density functional theory calculation, FeCoP2 yields the smallest Gibbs free energy change of rate-determining step among the samples, which leads to better electrochemical performances. In addition, when FeCoP2@NPPC was used as a bifunctional catalyst in water splitting, the electrolyzer needed a low voltage of 1.60 V to deliver the current density of 10 mA cm-2. Furthermore, this work provides a strategy for preparing sustainable, stable, and highly active electrocatalysts for water splitting.

Occurrence and flow of hydrocarbons in nanopores are two important issues in the effective exploitation of shale oil reservoirs. In this study, molecular dynamics simulations are employed to investigate the mechanisms about occurrence and flow of octane in slit-shaped quartz nanopores. We show that the occurrence state of octane and, therefore, its flow behavior are profoundly affected by the potential field from quartz walls and adsorption layers if the nanopore width w becomes less than 50 Å. Two main adsorption layers are always formed, adjacent to the walls and independent of w, due to two potential wells generated by the attractive potentials of the walls. Each pair of symmetrical adsorption layers, each of which can be considered as a solid-like surface, forms a confined environment similar to a nano-slit. The attractive potentials from them are found to be the cause for the formation of the adsorption layers between them. The obvious bulk phase of octane is formed in the pore of w = 50 Å due to the wide zero potential barrier induced by the innermost two adsorption layers. The nonlinear dependence of flow rate on pressure gradient shows that Darcy's law fails to describe the flow in the nanopore. The non-Darcy behavior mainly arises from adsorption effects from the walls and the adsorption layers, slippage between octane and walls and between adjacent two adsorption layers, and the molecular exchange between adsorption layers. A modified microscopic model is established to predict the dependence of flow rate on potential field, pressure gradient and w, which is in a good agreement with our simulation results and verified by the dodecane flow through the nanopore. Our work can be of great importance for revealing the mechanisms of occurrence and transport and guiding the estimation and exploitation of shale oil resources.

A series of fully conjugated macrocycles Mn (n = 4–7) consisting of N-(3,5-di-tert-butyl-4-methoxyphenyl) substituted carbazole (Cz-Ar) were successfully synthesized. The aryl carbazole and macrocycle M4 can be readily oxidized and the corresponding radical cation species were found to be highly stable. Moreover, macrocycle M5 was found to form 1 : 1 stoichiometric complexes with fullerenes C60 and C70 with association constants as high as (8.38 ± 0.33) × 104 M−1 and (7.64 ± 0.26) × 104 M−1, respectively.

The design and fabrication of highly efficient artificial light-harvesting systems (LHSs) are of great importance in supramolecular chemistry and materials science. Benefitting from the convenient construction process of supramolecular self-assembly, herein, a dual-donor artificial LHS was efficiently constructed through hierarchical self-assembly approaches involving metal–ligand coordination interactions, host–guest interactions and hydrophobic interactions. Notably, compared to the model single-donor artificial LHS with only one donor chromophore, the prepared dual-donor artificial LHS exhibited higher energy transfer efficiency and antenna effects. This research provides an efficient strategy for the construction of artificial LHSs with high energy transfer efficiency and antenna effects.

Chiral assemblies by combining natural biomolecules with plasmonic nanostructures hold great promise for plasmonic enhanced sensing, imaging, and catalytic applications. Herein, we demonstrate that human serum albumin (HSA) and porcine serum albumin (PSA) can guide the chiral assembly of gold nanorods (GNRs) with left-handed chiroptical responses opposite to those by a series of other homologous animal serum albumins (SAs) due to the difference of their surface charge distributions. Under physiological pH conditions, the assembly of HSA or PSA with GNRs yielded left-handed twisted aggregates, while bovine serum albumin (BSA), sheep serum albumin, and equine serum albumin behaved on the contrary. The driving force for the chiral assembly is mainly attributed to electrostatic interaction. The opposite chiroptical signals acquired are correlated with the chiral surface charge distributions of the tertiary structures of SAs. Moreover, the chirality of the assembly induced by both HSA and BSA can be enhanced or reversed by adjusting the pH values. This work provides new insights into the modulation of protein-induced chiral assemblies and promotes their applications.

Health and wellbeing are significantly impaired by alcoholic liver disease (ALD), and although some lactic acid bacteria strains have been shown previously to relieve ALD symptoms, the mechanisms behind these effects are still unclear. Here, the Lieber-DeCarli liquid diet containing alcohol was fed to C57BL/6J mice for 6 weeks to build a chronic alcoholic liver lesion model to study the protective effects and possible mechanisms of Lactobacillus mixture (Lactobacillus plantarum KLDS1.0344 and Lactobacillus acidophilus KLDS1.0901). The results showed that Lactobacillus mixture improved intestinal epithelial permeability and reduced the serum lipopolysaccharide (LPS) levels. Furthermore, Lactobacillus mixture inhibited liver lipid accumulation, oxidative stress, and inflammation by regulating AMPK, Nrf-2, and TLR4/NF-κB pathways. Importantly, the Lactobacillus mixture modulated the gut microbiota, resulting in increased short-chain fatty acid (SCFA) producers and decreased Gram-negative bacteria. Taken together, these findings indicated that the Lactobacillus mixture could positively regulate the gut microbiota, causing increased levels of SCFAs, which inhibited alcohol-induced liver lipid accumulation and oxidative stress through the gut-liver axis. Moreover, following administration of the Lactobacillus mixture, the improvement of intestinal epithelial permeability and the reduction of Gram-negative bacteria led to the decrease of LPS entering the portal vein, thereby inhibiting alcohol-induced liver inflammation.

The metal salts KSCN, Ni(CH3COO)2·4H2O, and auxiliary ligand pyridine were added respectively to the salamo-like ligand H2L, and it is expected that the Ni(II) complex coordinated by H2L will be ob...

A photoredox-catalyzed regio- and stereoselective trifluoroethylation reaction of enamides using commercially available 2,2,2-trifluoroethyl iodide as trifluoroethylating agents has been developed,...

Mammalian carboxylesterases (CES) are key enzymes that participate in the hydrolytic metabolism of various endogenous and exogenous substrates. Human carboxylesterase 2A (hCES2A), mainly distributed in the small intestine and colon, plays a significant role in the hydrolysis of many drugs. In this study, 3-arylisoquinolones 3 h [3-(4-(benzyloxy)-3-methoxyphenyl)-7,8-dimethoxyisoquinolin-1(2H)-one] and 4 a [3-(4-(benzyloxy)-3-methoxyphenyl)-4-bromo-7,8-dimethoxyisoquinolin-1(2H)-one] were found to have potent inhibitory effects on hCES2A (IC50 =0.68 μΜ, Ki =0.36 μΜ) and excellent specificity (more than 147.05-fold over hCES1 A). Moreover, 4 a exhibited threefold improved inhibition on intracellular hCES2A in living HepG2 cells relative to 3 h, with an IC50 value of 0.41 μΜ. Results of inhibition kinetics studies and molecular docking simulations demonstrate that both 3 h and 4 a can bind to multiple sites on hCES2A, functioning as mixed inhibitors. Structure-activity relationship analysis revealed that the lactam moiety on the B ring is crucial for specificity towards hCES2A, while a benzyloxy group is optimal for hCES2A inhibitory potency; the introduction of a bromine atom may enhance cell permeability, thereby increasing the intracellular hCES2A inhibitory activity.

Redox-responsive ferrocene (Fc)-containing hydrogels have attracted increasing interest for their potential applications in materials science, biomedicine and catalysis. Herein, we report the synthesis of a novel polynorbornene-based tetrablock terpolymer containing consecutively aldehyde, Fc, and dentritic triethylene glycol and aldehyde groups in the side chain by the ring-opening metathesis polymerization with the aid of the 3rd generation Grubbs catalyst. Owing to the presence of Fc and triazole groups, this copolymer could be used as both reducing and stabilizing agents for the formation of silver nanoparticles (AgNPs). Also, this copolymer could be used as a crosslinking agent to fabricate gelatin hydrogels based on the Schiff's base reaction between the aldehyde groups and the side-chain amino groups of gelatin. Based on the above properties, the AgNPs composites of gelatin hydrogels were further successfully fabricated by blending this copolymer, gelatin and AgNO3 together or soaking this Fc-containing gelatin hydrogels into the AgNO3 solution, in which the AgI was in situ reduced into Ag0 by the Fc groups. Results of inhibition zone experiments confirmed the antibacterial activities of the obtained composites against both Escherichia coli and Staphylococcal aureus.

The correlation between aggregates and bound rubber structures in silicone rubbers (S(phr)) with various silica fractions (ΦSi) has been investigated by contrast matching small-angle neutron scattering (SANS), swelling kinetics, and low-field nuclear magnetic resonance (NMR). Mixed solvents with deuterated cyclohexane fractions of 4.9% and 53.7% were chosen to match the scattering length densities of the matrix (SMP(phr)) and the filler (SMS(phr)), respectively. All the data consistently suggest that: (i) There is a critical threshold ΦSic between 10 and 30 phr; below Φsic, the isolated aggregates are dominant, while beyond Φsic, some rubber fraction is trapped among the agglomerate; (ii) Φsr-independent thicknesses around 7.5 nm (NMR) and 8.6 nm (SANS) suggest that the bound rubber formation is determined by inherent properties of the components, and the power-law around 4.2 suggests an exponential changed gradient density of the bound rubber; (iii) SMS(80) presents a bicontinuous bound rubber with three characteristic lengths of 41, 100, and 234 nm. The expanded correlation length, a 20 nm smaller aggregate sizes suggest that such existent bicontinuous network in dry samples with less ΦSi is kind of impacted by swelling. With the obtained bound rubber models, the reinforcing mechanism of filled silicone rubber is elucidated.

In order to expand the family and improve the bioactivity of oral implant ceramics, the phase structures, mechanical and wetting properties of the hot-pressed yttria-zirconia/multilayer graphene oxide composite (3Y-ZrO2/GO) ceramics were investigated. GO was uniformly distributed in 3Y-ZrO2 powders, forming the C–O–Zr bond during the sintering process. In comparison to raw 3Y-ZrO2 ceramics, the flexural strength and fracture toughness improved up to 200% (1489.96 ± 35.71 MPa) in ZG3 (with 0.15 wt% GO) and 40.9% (8.95 ± 0.59 MPa m1/2) in ZG2 (with 0.1 wt% GO), respectively, while the relative density and Vickers hardness increased slightly. The toughening mechanisms included crack deflection, crack bridging, and GO put-out. Meanwhile, the composite ceramics were transformed into a more hydrophilic direction and indicated a good wetting property. In consideration of mechanical and wetting properties, the ZG3 would be a favorable alternative to the yttria-zirconia ceramic (Y-TZP) in dental implant applications. The results are expected to serve as a technical guidance for the fabrication and evaluation of dental implants.

A new asymmetric salamo-based ligand (H2L) was synthesized and upon reaction with Cu(ClO4)2 an extremely rare dinuclear Cu(II) complex [Cu2(L)2] was formed and characterized by elemental analyses, ...

Nb-doped SrSnO3 (SSNO) thin films were epitaxially grown on LaAlO3(001) single-crystal substrates using pulsed laser deposition under various oxygen pressures and substrate temperatures. The crystalline structure, electrical, and optical properties of the films were investigated in detail. X-ray diffraction results show that the cell volume of the films reduces gradually with increasing oxygen pressure while preserving the epitaxial characteristic. X-ray photoelectron spectroscopy analysis confirms the Nb5+ oxidation state in the SSNO films. Hall-effect measurements were performed and the film prepared at 0.2 Pa with the 780 °C substrate temperature exhibits the lowest room-temperature resistivity of 31.3 mΩcm and Hall mobility of 3.31 cm2/Vs with a carrier concentration at 6.03 × 1019/cm3. Temperature-dependent resistivity of this sample displays metal-semiconductor transition and is explained mainly by electron-electron effects. Optical transparency of the films is more than 70% in the wavelength range from 600 to 1800 nm. The band gaps increase from 4.35 to 4.90 eV for the indirect gap and 4.82 to 5.29 eV for the direct by lowering oxygen pressure from 20 to 1 × 10−3 Pa, which can be interpreted by Burstein-Moss effect and oxygen vacancies generated in the high vacuum.

Clerodendranthus spicatus, popularly known as "kidney tea" in China, is consumed traditionally as a functional food for treatment of renal inflammation, dysuria, and gout. We evaluated the effects of C. spicatus on gout by assessing activities of antihyperuricemia, anti-gouty arthritis, and analgesia in vivo, and the results indicated that the ethyl acetate fraction shows potential activities. Subsequent phytochemical investigation of this fraction led to the isolation of 32 compounds, consisting of 20 diterpenoids (including the new orthosiphonones E and F), 2 triterpenoids, 6 flavonoids, 2 lignanoids, and 2 phenolic acid derivatives. Pharmacological investigation of the pure compounds in the cellular model of hyperuricemia indicated that 12 compounds could promote the excretion of uric acid at 10 μg/mL, and compounds 3, 4, 5, and 21 had better effects than that of benzbromarone, a famous uricosuric drug. Furthermore, compounds 4, 6, 7, 9, 14, 15, 23, 26, and 31 showed significant anti-gouty arthritis activity in monosodium urate (MSU)-induced joint swelling at the dose of 50 mg/kg, while compounds 4, 5, 7, 9, and 26 exhibited significant inhibition of pain induced by acetic acid. Our findings provided scientific justification to support the traditional application of "kidney tea" for treating gout and suggested its good application prospects in the future.

Adriamycin resistance in HCC seriously hinders the treatment of patients, it is necessary to investigate the mechanisms. Autophagy is involved in adriamycin resistance and JNK2 is related to autophagy. However, whether JNK2 inducing drug resistance though autophagy is unknown. GL-V9, a new synthesized flavonoid derivative, has been proved of its anti-tumor effects. The aim of the study is to explore the role of JNK2-related autophagy on adriamycin-induced drug resistance and the effects of GL-V9 on reversing adriamycin resistance. We concluded that JNK2 played an important role in drug resistance induced by adriamycin. The high expression of JNK2 activated protective autophagy in Hep G2-DOXR cells under non-stress condition, which protected cells from drug attacking. Furthermore, we found that GL-V9 reversed adriamycin resistance by blocking the JNK2-related protective autophagy in HCC.

An unexpected bistricyclic aromatic ene AF was synthesized in a tin(II) chloride-mediated reductive aromatization reaction. The obtained AF showed a highly overcrowded structural conformation as revealed by X-ray crystallography. Interestingly, AF exhibited reversible high-contrast mechanochromism and thermochromism between pale and red color. The obvious chromism is likely ascribed to the conformation transformation and trace amount of diradical species formation upon stimulus.

An ultrafine tin dioxide/N, P-doped porous carbon (SnO2/NPPC) nanocomposite is prepared through in-situ growth of tin dioxide (SnO2) nanoparticles in N, P-doped porous carbon (NPPC). Owing to the in-situ growth method, the size of SnO2 nanoparticles in SnO2/NPPC is quite small and uniform (generally less than 5.0 nm). NPPC provides a support and a conductive carbon skeleton for the SnO2 nanoparticles. The small SnO2 nanoparticles are less likely to aggregate during the discharge–charge process due to the presence of Sn–O–C bonding and nanoconfinement effect of SnO2 nanoparticles in carbon matrix. The N and P doping can provide abundant defects to facilitate the penetration of Li+ or Na+ into the interior of the electrode. In addition, the presence of Sn–N bonding can further improve the electrochemical properties of the electrodes. Thus, as an anode material for lithium-ion batteries, SnO2/NPPC possesses an enhanced rate performance, an excellent cycling stability, and a high initial Coulombic efficiency. The structure of the ultrafine SnO2 nanoparticles is well maintained in cycled SnO2/NPPC. Meanwhile, SnO2/NPPC also possesses good electrochemical performance as an anode for sodium-ion batteries. The good electrochemical properties for SnO2/NPPC materials can be ascribed to the synergetic effect between small SnO2 nanoparticles and NPPC.

This study aims for a better understanding of social networks (SN) regarding sustainable apparel. This study utilises a quantitative, online survey research approach of U.S. consumers to understand...

The design of highly efficient catalysts for the cleavage of various lignin linkages is the key step in the depolymerization of lignin. In this paper, strong-base-modified covalent triazine framewo...

Li-rich layered oxides are the most promising cathode candidate for lithium ion batteries with high specific energy. In this work, Li1.13Mn0.47Ni0.2Co0.2O2-coated Li [Li0.2Mn0.52Ni0.13Co0.13 V0.02]O2 cathode materials were synthesized via a sol–gel method, and their electrochemical performance was evaluated. Structural and morphological characterizations of the materials demonstrate that Li[Li0.2Mn0.52Ni0.13Co0.13V0.02]O2 particles are covered by Li1.13Mn0.47Ni0.2Co0.2O2 particles. Moreover, the Li1.13Mn0.47Ni0.2Co0.2O2 coating has no obvious effect on the crystal structure of Li-rich materials. The specific capacity, cycle performance, and rate capability of Li-rich materials are significantly improved with the coating of Li1.13Mn0.47Ni0.2Co0.2O2. Materials coated with 1 wt% to 3 wt% Li1.13Mn0.47Ni0.2Co0.2O2 exhibit the highest capacity retention of 93% after 100 cycles at 1 C, which is 10% higher than that of the uncoated one. The specific capacity of 3 wt% Li1.13Mn0.47Ni0.2Co0.2O2-coated material is 115.9 mAh g−1 at 5 C, and that of the blank sample is 89.8 mAh g−1 under the same condition. The cyclic voltammetry and electrochemical impedance spectra reveal that the enhanced cycle performance and rate capability of the surface-modified Li-rich materials are due to the presence of the Li1.13Mn0.47Ni0.2Co0.2O2 coating layer, which restrains structural transformation with cycling and decreases the charge-transfer resistance of the materials.

The electrochemical methods for microRNA (miRNA) detection have received increasing attention because high portability and affordability of electrochemical biosensors may facilitate point-of-care quantitative detection of miRNAs. Among these biosensors, the homogenous label-free electrochemical biosensors for miRNAs are rarely reported due to the lack of a universal and efficient signal read-out-mode. A newly discovered G-triplex, 5′-CTGGGAGGGAGGGA-3’ (denoted as G3), can specifically bind with methylene blue (MB), leading to a significant decrease of the diffusion current of MB. By using miRNAs as a driving force, a two-stage isothermal exponential amplification reaction was proposed to generate G3 through miRNAs. The generated G3 can combine with MB and produce observable current changes, which depend on the concentration of miRNAs. Therefore, a novel homogeneous label-free electrochemical biosensor for miRNA detection was successfully constructed. By choosing let-7a, the down-regulation of which is possibly associated with the over-expression of RAS and HMGA2 oncogenes, as a model, we discovered that this biosensor demonstrated excellent analytical performance in detecting let-7a, with an ultralow limit of detection (0.45 fM) and high specificity (discriminating one nucleotide variation). Moreover, the proposed biosensor was successfully applied in monitoring the expression levels of the low-abundant miRNAs in the human lung adenocarcinoma cell lines. This assay successfully verified the feasibility of G-triplex/MB as an efficient and sensitive probe for immobilization-free and label-free electrochemical detection of nucleic acids, which would greatly promote the rapid development of homogeneous label-free electrochemical biosensors.

Four coordination polymers ∞2 [Ni(DMF)(L)Ln(bdc)1.5] (Ln = La (1) and Nd (4)) and ∞2 [Ni2(DMF)2(L)2Ln2(bdc)3]·CH3OH (Ln = Ce (2) and Pr (3)) were derived from a symmetrical salamo-based ligand (H2L) with Ni(OAc)2·4H2O, Ln(NO3)3·6H2O (Ln = La, Ce, Pr and Nd), and H2bdc (terephthalic acid). Coordination polymers 1–4 were synthesized and characterized by elemental analyses, X-ray single crystal diffraction, infrared spectroscopy and ultraviolet–visible absorption spectroscopy. Coordination polymers 1–4 have similar structures exhibiting two-dimensional coordination polymers with brick wall in which [Ni(DMF)(L)Ln] units were linked by exodentate (bdc)2− linker. In each unit, Ni(II) atoms adopted a slightly distorted octahedral geometry, the Ln(III) atoms were nine-coordinated, and the coordination polyhedron was a distorted tricapped trigonal prism. The crystal structure and supramolecular features were discussed in detail. At the same time, the fluorescent properties of coordination polymers 1–4 were also investigated.

Chemokine receptor CXCR4 and its natural ligand CXCL12 (also known as stromal cell-derived factor-1, or SDF-1) regulate a broad range of physiological functions. Dysregulation of the CXCL12/CXCR4 axis is involved in numerous pathological conditions such as HIV infection, inflammation and cancer. Herein, we report the design, synthesis, and characterization of novel CXCR4 antagonists based on cyclic amine scaffolds. Compound 24 was identified as a potent CXCR4 receptor antagonist (competitive inhibition of 12G5 binding, IC50 =24 nM; functional inhibition of CXCL12-induced cytosolic calcium increase, IC50 =0.1 nM). In addition, compound 24 potently inhibited cell migration in CXCR4/CXCL12-mediated chemotaxis in a matrigel invasion assay. The absolute configuration of compound 24 was elucidated by X-ray crystallography.

Human aldo-keto reductase family 1 member C3 (AKR1C3) is known as a hormone activity regulator and prostaglandin F (PGF) synthase that regulates the occupancy of hormone receptors and cell proliferation. Because of the overexpression in metabolic diseases and various hormone-dependent and -independent carcinomas, as well as the emergence of clinical drug resistance, an increasing number of studies have investigated AKR1C3 inhibitors. Here, we briefly review the physiological and pathological function of AKR1C3 and then summarize the recent development of selective AKR1C3 inhibitors. We propose our viewpoints on the current problems associated with AKR1C3 inhibitors with the aim of providing a reference for future drug discovery and potential therapeutic perspectives on novel, potent, selective AKR1C3 inhibitors.

In this work, hyperbranched polyurethane elastomer (HBPUE) electrolyte and aluminum foil (Al) were joined together by anodic bonding. It provides a possibility for packaging of flexible devices to use anodic bonding. The HBPUEs were designed and prepared via prepolymerization method cured at room temperature using polypropylene glycol (PPG), toluene-2,4-diisocyanate(TDI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and the varying ratios of trimethylolpropane (TMP)/1,4-butanediol (BDO). All HBPUEs prepared exhibited low glass transition temperature (Tg) and good thermal stability. The highly branched structures increase the proportion of amorphous phase of HBPUEs, resulting in a high ionic conductivity with a highest value of 2.38 × 10−4 S cm−1 at 70 °C when adding TMP and BDO at the ratio of 0.45:0.45 (HBPUE3). There are no obvious diffraction peaks of the LiTFSI in the XRD patterns, indicating that LiTFSI was dissolved in polyurethane matrix completely. XRD results show that the structures of PEO-PUEs are amorphous. The HBPUEs prepared have good mechanical properties that can be used as packaging material. After bonded, the microstructures of the bonded interface between HBPUE and Al with a clear intermediate bonding layer could be observed by the cross-sectional scanning electron microscopy (SEM) images, and the elements diffused were also detected by the energy-dispersive spectrometer (EDS), indicating that the HBPUEs and Al were bonded together successfully. The maximum tensile strength for HBPUE3/Al was up to 1.15 MPa. All results demonstrated that the HBPUEs prepared would be a promising packaging material for flexible devices applied to anodic bonding.

Supercritical CO2 Brayton cycle has been highly recommended as a promising power cycle. As a method to improve the cycle performance, some trace gases could be introduced in the system. Due to rare viscosity coefficient data of CO2-based mixtures over the supercritical regions of CO2, the effect of trace gas on the characteristics of pressure drop has not been clarified yet. Thus, it leads to a challenge in the design and optimization of the supercritical CO2 Brayton cycle when mixing working fluid is considered. In this work, microamount Xe, the mol fraction of which ranges from 1 % to 5 %, is considered as an additive gas. The viscosity coefficient of CO2-Xe was calculated using molecular dynamics simulation. A reliable simulation strategy for the viscosity coefficient calculation was formed, which was proved available since the average relative error of the simulated viscosity coefficient of pure CO2 is around 1 % compared to the REFPROP database. Then, the influence of the addition of Xe on the viscosity coefficient and the pressure drop of the recuperator was discussed. The results demonstrate that the viscosity coefficient would change a lot when CO2 is mixed with Xe. A relative change of viscosity coefficient of 66 % can be observed. Consequently, the pressure drop of the recuperator could enlarge a lot reaching up to 12 %. This work suggests that attention must be paid to the changed viscosity during the design for a reasonable prediction when the trace gas is introduced into the system.

Abstract Indole alkaloids extract (IAAS) was prepared from leaves of Alstonia scholaris (L.) R. Br., an evergreen tropical plant widely distributed throughout the world. This plant has been used historically by the Dai ethnic people of China to treat respiratory diseases. This study evaluated the genotoxicity and safety pharmacology of IAAS to support clinical use. The bacterial reverse mutation (Ames) test, in vitro mammalian chromosomal aberration test, and in vivo mammalian erythrocyte micronucleus (MN) test were performed to evaluate genotoxicity. Mice were administered IAAS (240, 480, or 960 mg/kg bw) once orally to observe adverse central nervous system effects. Furthermore, beagle dogs were administered IAAS (10, 30, 60 mg/kg bw) once via the duodenum to evaluate its effects on the cardiovascular and respiratory systems. IAAS with or without S9-induced metabolic activation showed no genotoxicity in the Ames test up to 500 μg/plate, in the mammalian chromosomal aberration test up to 710 μg/mL, or in the MN test up to 800 mg/kg bw. No abnormal neurobehavioral effects were observed in mice following treatment with up to 960 mg/kg bw of IAAS. Moreover, blood pressure, heart rate, electrocardiogram parameters, and depth and rate of breathing in anesthetized beagle dogs did not differ among the IAAS doses or from the vehicle group. These data indicated that IAAS did not induce mutagenicity, clastogenicity, or genotoxicity, and no pharmaco-toxicological effects were observed in the respiratory, cardiovascular, or central nervous systems. Our results increased understanding of safety considerations associated with IAAS, and may indicate that IAAS is a possible drug candidate. Graphic Abstract

A fiber strain sensor which is formed by cascading an optical microfiber coupler and a Sagnac loop is proposed and studied. The optical microfiber coupler, and the Mach-Zehnder interferometer formed between the optical microfiber coupler and the Sagnac loop can serve as different strain sensing elements, used for different types of strain measurement. The optical microfiber coupler is mainly responsible for precisely sensing small scale strain variations, and the Mach-Zehnder interferometer focuses on measuring strain in large operation range. The operating principle of this sensor is theoretically analyzed, and the experimental sensing spectra are in consistent with the simulated results.

Phenolic compounds are considered the main bioactive components in kiwifruit. In order to well understand the accumulation pattern of health-beneficial phenolics, and to obtain high-quality kiwifruits with health-promoting characteristics, the changes of physicochemical properties, phenolic compounds, antioxidant capacities, and inhibitory effects on digestive enzymes of “Donghong” kiwifruits during maturation were systematically investigated. Noticeable variations in physicochemical properties and phenolic profiles were observed throughout the maturation stages of “Donghong” kiwifruit. According to the HPLC analysis, phenolic compounds, including chlorogenic acid, (−)-epicatechin, procyanidin B2, quercetin-3-O-rhamnoside, gallic acid, neochlorogenic acid, and caffeic acid, were found in “Donghong” kiwifruit, while chlorogenic acid was the most abundant phenolic compound. Considering the accumulation patterns of both total phenolics and soluble solids content, the optimum harvest time of kiwifruit with relatively high level of health-beneficial components was determined. Furthermore, “Donghong” kiwifruit exerted remarkable antioxidant capacities, and inhibitory effects on pancreatic lipase and α-glucosidase. Indeed, the Pearson’s correlation showed that chlorogenic acid, caffeic acid, (−)-epicatechin, and quercetin-3-O-rhamnoside could be major contributors to the antioxidant activity and inhibitory effects on digestive enzymes. Results are beneficial for better understanding of the accumulation patterns of health-beneficial phenolic compounds, which can aid in the targeting of specific developmental stages with an optimal phenolic profile for the production of health-beneficial products.

The fruits of Lycium barbarum have a long history as an edible and medicinal food in Asian regions and have multiple consumption methods; the polysaccharides (LBPs) are commonly considered as their major immunological constituents. The current study revealed that the total phenolic amide moieties from L. barbarum fruits showed greater potential immunomodulatory activity in vivo than did LBPs. Through subsequent investigation on the immunological bioactive phenolic amides, three new phenolic amides, lyciumamides L-N (1-3), as well as 12 analogues, were obtained from the total phenolic amide fraction. Extensive spectroscopic methods were used to elucidate the new structures. Compounds 4-6 and 15 significantly promoted LPS-stimulated B splenocyte, while compounds 4-6 displayed accelerative effects on the proliferation of Con A-stimulated T lymphocytes at a concentration of 20.0 μg/mL. These data indicated that extracts from L. barbarum fruits enriched with phenolic amides could be developed as a nutritional dietary supplement for immunocompromised individuals.

Background: Volatile compounds in fish sauce may vary due to the species of fish, ingredients, processing period, temperature, and even the preference of people in each area. It is necessary to study a method of distinguishing the origins of fish sauce. The aims of this paper are to introduce a method to classification of fish sauce origin by means of electronic nose fingerprint and gas chromatography- mass spectrometry of volatile compounds and the two artificial neural networks are used to predict the origins of fish sauce. Methods: Headspace sampling-solid phase microextraction combined with gas chromatography-mass spectrometric analysis and electronic nose were used to analysze volatile compounds in different origins of fish sauce, and these dates predicted the origins of fish sauce by artificial neural networks. Results: 94 volatile compounds were identified by Automatic mass spectral deconvolution and identification system, out of which 44 are from Guangdong, 53 from our laboratory, 51 from Vietnam, 47 and 45 from Thailand. Then electronic nose was applied to identify the origin of fish sauce, and the data were analyzed using principal component analysis and load analysis. The fish sauce from different origin can be classified well on the PCA plot. Lastly, two artificial neural networks are used to predict the origins of fish sauce, and the accuracy rates of radial basis and gradient descent both are 93.33%. Conclusion: That illustrates that we can provide a quick method to distinguish fish sauce products of different origins. These results indicated that the combinations of multiple analysis and identification methods could make up the limitations of a single method, enhance the accuracy of identification, and provide useful information for product development.

The transitions between surfactant aggregate structures are triggered by changes in chemical or physical stimulations, including addition of additives. Effects of added alcohols on aggregate morphologies correlate strongly with alcohol chain length. The local molarities of alcohol, water, and counterions in the interfacial regions play an important role in controlling the aggregate morphologies. However, direct experimental estimates of changes of interfacial alcohol molarities during alcohol induced micelle-to-vesicle transitions have never been reported. Ellipsoidal-wormlike micelle-vesicle transitions in CTAB/KBr aqueous solutions in the presence of long-chain octanol were characterized by using combined rheological, dynamic light scattering (DLS), transmission electron microscopy (TEM) and turbidity measurements. However, the transitions are absent with added butanol. The chemical trapping method (CT) was employed to understand the differences between medium- and long-chain alcohols in determining aggregate morphology. The CT method was used to estimate interfacial water, alcohol, and counterion molarities with increasing stoichiometric alcohol concentrations. With 55 mM alcohol added, the interfacial octanol molarity is 0.9 M, which is three times higher than that for butanol. With added octanol, the ellipsoidal-wormlike micelle-vesicle transition is accompanied by a concurrent sharp increase of interfacial water molarities and a decrease of interfacial counterion molarity, which is not observed with added butanol. The CT data was also employed to estimate the changes of Israelachvili's packing parameter with increasing added alcohol concentration. Our result provides critical molecular level information for understanding the morphological transitions of CTAB/additives.

Gentiana rigescens is a traditional Chinese medicine with efficacy in liver protection, as a cholagogic, anti-hyperglycemic, and anti-hypertension agent, and in relieving spasms and pain. The geographical environments of different locations are very complicated, with different soils, climates, sun exposure, etc.; this has a remarkable effect on the quality of medicinal herbs. To identify different geographic origins of G. rigescens, we analyzed the high-performance liquid chromatography (HPLC) and Fourier transform infrared spectroscopy (FTIR) fingerprints of G. rigescens with the aid of chemometrics. Five variable selection methods, including competitive adaptive reweighted sampling (CARS), random frog (RF), subwindow permutation analysis (SPA), Monte Carlo uninformative variable elimination (MC-UVE) and genetic algorithms (GA), were used to screen the characteristic variables for both the HPLC and FTIR fingerprints. Then, the corresponding partial least squares discriminant analysis (PLS-DA) models were built. The results showed that for both HPLC and FTIR, the GA-PLS-DA models were the most robust models for identification of the geographical origins of G. rigescens, which indicated that the recognition results of HPLC and FTIR are consistent. Through HPLC–FTIR two-dimensional (2D) hetero-correlation analysis, the results showed a substantial correlation between HPLC and FTIR, which suggests that spectral correlative chromatography for multicomponent comparison can be conducted. In terms of G. rigescens, qualitative identification using FTIR is more convenient, rapid, environment-friendly and inexpensive than that using HPLC.