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Elizabethkingia meningoseptica is a non-fermentative Gram-negative bacillus that has emerged as an important pathogen in nosocomial infections and is usually associated with high mortality. E. meningoseptica is inherently resistant to many broad-spectrum antibiotics, and appropriate antibiotic selection is crucial for survival. Data about the therapeutic efficacy of fluoroquinolone in E. meningoseptica bacteraemia are limited. We retrospectively enrolled patients with E. meningoseptica bacteraemia who were treated with a single antimicrobial agent with in vitro activity against E. meningoseptica for at least 48 hours in a Taiwanese medical centre between January 2011 and June 2016. We compared the therapeutic efficacy of fluoroquinolone and non-fluoroquinolone treatment. A logistic regression and a propensity score-adjusted model were used to evaluate the risk factors for 14-day mortality. A total of 66 patients were identified, 24 who received fluoroquinolone treatment (ciprofloxacin, n = 9; levofloxacin, n = 15) and 42 who received non-fluoroquinolone treatment (piperacillin/tazobactam, n = 26; trimethoprim/sulfamethoxazole, n = 15; minocycline, n = 1). The fluoroquinolone group had significantly lower 14-day mortality than the non-fluoroquinolone group (8.3% vs. 33.3%, P  = 0.023). The APACHE II score was significantly higher in the non-fluoroquinolone group than in the fluoroquinolone group. In a propensity-adjusted analysis, fluoroquinolone use was an independent factor associated with 14-day survival. After stratification using the APACHE II score, treatment with fluoroquinolone was associated with 14-day survival, but did not reach statistical significance in both groups with greater and lesser severity. Therefore, fluoroquinolone is a suitable antimicrobial agent for treating E. meningoseptica bacteraemia. [ABSTRACT FROM AUTHOR]

[Display omitted] • Robust PU/SiO 2 nanohybrids with a tensile strength of 35.5 MPa and over 700 % elongation at break. • Nanohybrids prepared from polymer waste conversion process with an approximately 98% functional group selectivity. • Nanohybrids exhibiting particle sizes ranging from 100 to 500 nm. • PU/SiO 2 membrane involving CO 2 reuse with a P CO2 of 24.02 barrer, and a selectivity of 32.85 (α CO2/N2). • Gas separation membranes for CO 2 capture and storage from post-consumption materials. In this study, polymer nanocomposite membranes with recyclability were developed to achieve good mechanical properties and gas permeability in the consumption of a recycled polymeric material. The newly developed process has been realized through the conversion of waste PC to afford key intermediates containing alkoxysilane and phenolic groups. The alkoxysilanes would act as the nucleation sites for sol–gel reactions, whereas the phenolic groups further provided active hydrogens for click reactions in the production of polyurethane/silica (PU/SiO 2) nanohybrids, exhibiting microcavity to facilitate gas molecules diffusion for membrane with improved gas permeability. Moreover, the additional use of aliphatic polycarbonate polyol provided enhanced CO 2 solubility for gas separation membranes of the PU/SiO 2 nanohybrids with a P CO2 permeability of 24.02 barrer and a selectivity of 32.85 (α CO2/N2), which approached the 2008 Robeson upper bounds. Moreover, the joint presence of polycarbonate polyol and silica in the nanohybrids led to high-performance elastomeric properties, with tensile strengths of 35.5 MPa and over 700 % elongation at break, results that exceeded those of previously reported PU-based gas separation membranes. Notably, this PC recycling process featured the newly formed carbamate groups as the reaction sites, enabling the recyclability of PU/SiO 2 nanohybrids as the gas separation membranes for CO 2 capture and storage in post-consumption materials. [ABSTRACT FROM AUTHOR]

Abstract: A new electrochromic norbornene derivative (NB) containing symmetrical diphenylamine and unsymmetrical triphenylamine groups, was synthesised from norbornene amine and unsymmetrical triphenylamine-substituted bromide. NB was used to obtain unsaturated PNB via ring-opening metathesis polymerization using different Grubbs'' catalysts, followed by hydrogen reduction to obtain saturated HPNB. PNB and HPNB were highly soluble in common organic solvents such as toluene, xylene, benzene, chlorobenzene, 1,2-dichlorobenzene, and tetrahydrofuran at room temperature. The glass transition temperatures (T g ) of PNB and hydrogenated HPNB were 162 °C and 117 °C, respectively. The 10% weight-loss temperatures of PNB and hydrogenated HPNB were 410 °C and 450 °C, respectively. Cyclic voltammogram of HPNB film cast onto an indium-tin oxide (ITO)-coated glass substrate exhibited three reversible oxidation redox couples at 0.52, 0.85 and 1.30 V versus Ag/Ag+ in acetonitrile solution. The electrochromic characteristics of HPNB showed excellent stability and reversibility, with multi-staged colour changes from light yellow to green, dark-blue and purple as the potential changed from 0 to 1.35 V. The colour switching time and the bleaching time of the HPNB were 8.7 s and 4.3 s, respectively, at 1084 nm and 7.9 s and 3.8 s at 879 nm. [Copyright &y& Elsevier]

Polymer properties along with recycling processes remain a constant challenge for post-recycled polymers. In this study, the development of recycling feasibility, monomers reactivity, and the chemical-recycled polymer properties from polycarbonate (PC) waste were demonstrated. Through selective aminolysis under mild conditions, the reduced molecular-weight products (or monomer mixtures) with newly incorporated flexible-ether linkages as building blocks were realized. By using the commodity monomers such as isocyanate reagents, monomer mixtures were readily to be re-connected into polyurethanes in one-pot process without prior purification of the recycled monomer mixtures. Due to the presence of urethane groups, the enhanced reactivity of the terminal phenolic hydroxyl groups of the monomer mixtures toward isocyanate groups would afford high molecular weights over ~80,000 g/mol for thermoplastic polyurethanes (TPUs). Moreover, by taking advantage of low melting point polyether-type polyols along with optimizing processing conditions, the TPUs exhibited a unique phase separation morphology with domain sizes ranging from ~10 nm to ~25 nm as investigated by using small angle X-ray scattering (SAXS) measurements. This work demonstrate that the PC waste was fully transformed into TPUs which exhibited improved elastomeric properties. This work demonstrates that the PC waste was depolymerized to monomer mixtures and subsequently transformed into recyclable thermoplastic polyurethanes exhibiting robust elastomeric properties. Image 1 • Monomer mixtures derived from the aminolysis of polycarbonates. • Thermoplastic polyurethane elastomers prepared from recycled monomer mixtures. • Diphenolic carbamates as hard segments for TPUs. • Ｍicrophase separation and semi-crystallinity morphologies. • Tensile properties comparable with those of TPUs prepared from pristine raw materials. [ABSTRACT FROM AUTHOR]

Over the years, the manipulation of polymer microphase separation associated with molecular architectures has been holding great promise for rendering structure-property relationship. A series of poly (urea/malonamide) dendrons bearing rigid adamantanes in the periphery were developed to serve as branching hard segments (HS) for thermoplastic polyurethanes (TPUs) either in end-capping or pendant manner. Thermal properties, crystalline structures, and mechanical properties of the TPUs were investigated by DSC, X-ray scattering, and DMA, respectively. The introduction of the branching units with bulky adamantanes would expectedly hinder the crystallization of HS. Intriguingly, the dendrons not only accelerate the crystallization of the soft segment (SS, based on polycaprolactone polyol (PCL)), but promote the phase separation between HS and SS to form distinct microdomains as well. These enhanced effects revealed a size-dependent relationship with growing size (or generation) of the branching HS. With the high SS crystallinity that can freeze the chain mobility and the robust HS domains that work as the physical crosslinking points, the resulting TPUs incorporated with adamantane-bearing units show superior shape memory behaviors. This work demonstrates that the molecular engineering on the architectures can significantly tailor the microstructures and properties of thermal plastic polymers. Image 1 • Preparation of dendrons bearing rigid adamantanes in periphery. • Adamantane-containing dendrons as hard segments for TPUs. • The crystallization of hard segments in TPUs hindered by bulky branching units. • The crystallization of the soft segment accelerated by the presence of bulky dendrons. • Shape memory properties enhanced by distinct microphase separation in TPUs. [ABSTRACT FROM AUTHOR]

Water-dispersible polymers represent an evolved category in the chemical industry in terms of an eco-friendly technology to meet the desired performance and to reduce the use of volatile solvents. One of the major challenges in the development of water dispersible resins deeply relies on the emulsification process that often requires the ionization process or the use of additional surfactants. In this study, an efficient method for the preparation of amphiphilic comb-like poly(hydroxyaminoethers), which consists of hydrophobic epoxy resins as the backbone and hydrophilic polyethers as the side chains, were realized in the absence of catalysts or initiators. Different from the conventional epoxy resin dispersions prepared in the presence of surfactants, or through ionization process, these amphiphilic comb-like polymers exhibited self-dispersed properties to achieve stable non-ionic emulsions in the water. The hydrophilic contents of these comb-like poly(hydroxyaminoethers) could be easily tailored in a wide range from less than 20 wt% to over 65 wt%, along with glass transition temperatures ranged from −45 °C to ~ 50 °C. In addition, the emulsifying ability was facilitated via the variations of the polymer architectures and compositions. Anti-corrosion properties were also evaluated for these self-dispersible poly(hydroxyaminoether) emulsions. Image 1 • Preparation of amphiphilic comb-like poly(hydroxyaminoethers). • Amphiphilic comb-like polymers with self-dispersed properties in water. • Thermally stable at temperatures over 300 °C, featuring tunable T g s from −45 to 50 °C. • Water dispersible characteristics with a size of 0.13 μm and a polydispersity of 0.029. • Pass anti-corrosion tests on the steel surfaces according to ASTM B117. [ABSTRACT FROM AUTHOR]

• Minocycline improved the survival of Galleria mellonella and mice infected with susceptible Elizabethkingia anophelis and reduced the tissue bacterial load of mice. • Reduced minocycline susceptibility (MIC of 4 mg/L) due to spontaneous mutation was associated with poor treatment outcomes in Galleria mellonella and mice. • The addition of rifampin (1 mg/L) reduced the mutant prevention concentration of minocycline from 2–4 mg/L to < 0.5 mg/L. • Rifampin combined with minocycline was synergistic in vitro , but conferred no in vivo benefit. Elizabethkingia anophelis is inherently resistant to multiple antibiotics, except minocycline. This study aimed to determine the in vitro and in vivo efficacy of minocycline monotherapy and combination therapy against susceptible strains and the impact of reduced minocycline susceptibility. Three clinical isolates and one laboratory-induced mutant with reduced minocycline susceptibility were included. Time-kill and checkerboard assays were used to assess in vitro efficacy and synergy, respectively. Galleria mellonella infection and mouse pneumonia models were used to assess in vivo efficacy, and a mouse thigh infection model was used to determine the bacterial load. Minocycline monotherapy exerted a modest inhibitory effect on three clinical minocycline-susceptible E. anophelis isolates in vitro , but delayed G. mellonella death and improved infected mouse survival; it also significantly reduced the in vivo bacterial load. Minocycline had decreased efficacy on G. mellonella and mice infected by the mutant with reduced minocycline susceptibility. Genome comparison revealed several spontaneous mutations associated with reduced minocycline susceptibility. Among eight antibiotics tested in combination with minocycline, rifampin consistently showed in vitro synergy. The addition of rifampin (1 mg/L) reduced the mutant prevention concentration of minocycline from 2–4 mg/L to < 0.5 mg/L. However, compared with monotherapy, the combination of rifampin and minocycline did not further reduce the bacterial load or improve the survival of G. mellonella or mice. Minocycline monotherapy was in vivo effective against susceptible E. anophelis. Reduced minocycline susceptibility due to spontaneous mutation decreased its therapeutic efficacy. In combination with rifampin, it prevented the in vitro emergence of reduced susceptibility but did not provide additional in vivo survival benefit. [ABSTRACT FROM AUTHOR]

Abstract: Polyimides rank among the most heat-resistant polymers and are widely used in high temperature plastics, adhesives, dielectrics, photoresists, nonlinear optical materials, membrane materials for separation, and Langmuir–Blodgett (LB) films, among others. Additionally, polyimides are used in a diverse range of applications, including the fields of aerospace, defense, and opto-electronics; they are also used in liquid crystal alignments, composites, electroluminescent devices, electrochromic materials, polymer electrolyte fuel cells, polymer memories, fiber optics, etc. Polyimides derived from monomers with noncoplanar (kink, spiro, and cardo structures), cyclic aliphatic, bulky, fluorinated, hetero, carbazole, perylene, chiral, non-linear optical and unsymmetrical structures have been described. The syntheses of various monomers, including diamines and dianhydrides that have been used to make novel polyimides with unique properties, are reported in this review. Polyimides, with tailored functional groups and dendritic structures have allowed researchers to tune the properties and applications of this important family of high-temperature polymers. The synthesis, physical properties and applications of advanced polyimide materials are described. [Copyright &y& Elsevier]

• Preparation of regular through-pore polyimide membranes on filter paper using the breath-figure technique. • Regular through-pore membranes with high water permeance and high yeast and mud rejection. • Surface cleaning or backwash easy restore the fouled membrane. Regular through-pore membranes exhibit extremely high productivity and size-selective capabilities. Previous studies have demonstrated that the use of a polymer alone on a solid substrate surface hinders the formation of regular through-pore membranes. In this study, amphiphilic dendrons were used as surfactants to concentrate the functional groups and strengthen the weak bonding forces between the molecules, which is conducive to the formation of regular through-pores in the membrane. The amphiphilic dendrons were mixed with commercial-grade polyimide (PI) using chloroform as the solvent, and the solution was evenly coated on the surface of the filter paper. Using the breath-figure method, an ultrathin regular through-pore PI layer was formed directly on the surface of the filter paper. The SEM image shows that regular through-pores were formed only on the surface of the substrate. The preparation process used in this study eliminates the need to transfer ultrathin and weak membranes to the substrate surface, which simplifies the membrane-making process. Pure water and yeast solution filtration tests were conducted on the composite membrane prepared with a 5 mg/ml dendron solution. A pure water permeance of 118,826 L m-2h−1 bar−1 (LMH/bar) was obtained, the yeast solution permeance and rejection are 17,410 LMH/bar and 92.85 %, respectively. The yellow, turbid, muddy water was successfully purified to clean water. The original performance of the fouled membrane was restored after only 30 s of water flushing. This study proposes a new approach to fabricate high-efficiency regular through-pore PI composite microfiltration membranes. [ABSTRACT FROM AUTHOR]

In this study, novel dendritic urethane acrylate polymers were developed for the fabrication of robust honeycomb-like surfaces after exposure to a UV-crosslinking process. Through iterative synthesis based on a highly selective intermediate of 4-isocyanate-4′-(3,3-dimethyl-2,4-dioxo-azetidine)-diphenylmethane, poly(urea/malonamide) dendrons bearing peripheral methyl methacrylate end groups with well-defined structures were realized. A coating solution was prepared by the combined use of 30–70 wt% UA dendron acting as dendritic diluents and dendritic UA copolymers acting as amphiphiles that can fabricate honeycomb-like surfaces via a breath figure self-assembly process using water droplets as templates. The resulting film can be cured under UV light to achieve a robust honeycomb-like structure with a hexagonal structure exhibiting solvent-resistant properties in ethanol. Consequently, this solvent-resistant porous array can act as a substrate for the detection of vanishingly low concentrations of analytes that are aqueous insoluble via surface-enhanced Raman scattering analysis. • Novel synthesis of dendritic urethane acrylate copolymers • Development of UV-curable polymer surface with honeycomb-like structure • Realization of robust polymer surfaces with solvent resistance properties • Detection of aqueous insoluble analytes via surface-enhanced Raman scattering analysis [ABSTRACT FROM AUTHOR]

The effect of chemical composition and morphology of the surface layers of new polyaramide-containing sorbents on the mechanism of selective sorption of nucleic acids and proteins was investigated as compared to the previously studied sorbents modified with fluoropolymers and polyaniline (high-throughput materials providing one-step isolation of DNA from biological mixtures). A series of silica-based sorbents modified with polyaramides having consistently varying structure and containing the set of “key” structural elements (aromatic units and nitrogen atoms in the backbone, fluorinated groups), and various donor and acceptor moieties was prepared. The chemical composition of the polymer coatings was evaluated by X-ray photoelectron spectroscopy. The surface morphology was studied by scanning probe microscopy. The sorption properties were investigated by passing the mixtures containing DNA, RNA and proteins of different nature through the cartridges containing the obtained sorbents. All the investigated materials weakly retain double-stranded DNA but effectively retain RNA and proteins. The sorption capacity of the sorbents depends on the protein nature. The observed sorption behavior was shown to be determined by the chemical structure and not by the morphology of the polymer coating. It was proposed that similarity of the sorption properties of the series of chemically different polymers could be determined by similar total input of different sorption mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: A small organic molecule of 2,3-bis(5-bromothiophene-2-yl)acrylonitrile (DTDBAL) was synthesized for the first time and introduced into an active layer consisting of poly-3-hexylthiophene (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), in order to improve the performance of an inverted bulk heterojunction organic photovoltaic. The short-circuit current of the device was improved owing to the formation of a cascade band alignment of P3HT/DTDBAL/PCBM which enhanced the exciton dissociation and charge transport. Meanwhile, the open-circuit voltage and fill factor were simultaneously improved due to the optimization of the active layer morphology. The best power conversion efficiency achieved was 3.45% under simulated AM 1.5G illumination of 100mW/cm2, which is an increase of 36% compared to a solar cell without the additive and featuring only P3HT/PCBM as the active layer. [Copyright &y& Elsevier]

Abstract: To improve the pervaporation performance of thin-film composite membranes, novel thin-film composite membranes were prepared via interfacial polymerization by reacting 5-nitrobenzene-1,3-dioyl dichloride (NTAC) or 5-tert-butylbenzene-1,3-dioyl dichloride (TBAC) with triethylenetetraamine (TETA) on the surface of a modified polyacrylonitrile (mPAN) membrane (TETA-NTAC/mPAN and TETA-TBAC/mPAN). The effect of the acyl chloride monomers chemical structure on the pervaporation separation of an aqueous ethanol solution was investigated. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and water contact angle measurements were applied to analyze the chemical structure, surface chemical composition, surface roughness and hydrophilicity of the polyamide active layer of the composite membrane. To correlate the variations in the free volume of the polyamide active layers with the pervaporation performance, positron annihilation spectroscopy (PAS) experiments were performed with a variable monoenergetic slow positron beam. From the results of the PAS and XPS experiments, the S parameter, o-Ps annihilation lifetime τ 3 (corresponding to free volume size) and its intensity I 3 (corresponding to free volume concentration), the τ 3 and I 3 of TETA-NTAC polyamide layer (positron incident energy of 1–1.7 keV) were both higher than those of TETA-TBAC polyamide layer. The S parameter for TETA-NTAC polyamide layer was also higher than that of the TETA-TBAC polyamide layer even though the former was more crosslinking than that of the latter. In the aqueous ethanol solution dehydration experiments, the TETA-NTAC/mPAN membrane produced both a higher permeation rate and water concentration in the permeate than the TETA-TBAC/mPAN membrane. [Copyright &y& Elsevier]

Abstract: An optically active, conjugated polymer bearing unsymmetric pendant carbazole chromophores was prepared via the Suzuki coupling of 9,9-dioctylfluorene-2,7-diboronic acid and a novel pyridine-containing compound. The polymer had a T g of 192°C and T d10 at 437°C under a nitrogen atmosphere and exhibited absorption bands at 320–400nm and displayed an additional absorption bands at 380–480nm after protonation with aq. HCl solution. The photoluminescence of the polymer shifted from 360–460nm to 460–560nm after protonation and the photoluminescence quantum yield of the polymer in THF solution was 0.88. The emission color of the polymer film changed from blue (439nm) to yellow (551nm) under an applied bias voltage of 2.5V. [Copyright &y& Elsevier]

[Display omitted] • N-methylphenothiazine derived redox ionic liquid (NMP-IL) was synthesized. • NMP-IL shows superior ionic conductivity with high thermal stability. • An extremely low-driving voltage (0.6 V) electrochromic device (ECD) was reported. • The proposed ECD gives a large transmittance change and coloration efficiency. • The ECD exhibits good long-term cycling stabilities at elevated temperatures. A novel N-methylphenothiazine based ionic liquid (NMP-IL) was designed for achieving low-driving voltage electrochromic device (ECD) with thermal durability. NMP-IL was synthesized via a five-step reaction, including thionation, methylation, substitution, ionization, and anion exchange. By chemically bonding with the ionic liquid, NMP-IL exhibited a large optical contrast and high thermal stability simply to take the advantages of both NMP and ionic liquid features. Compared to NMP, NMP-IL would provide the electrolyte with a higher ionic conductivity, thus reducing the driving voltage of the ECDs. Most importantly, an extremely low-driving voltage (0.6 V) ECD based on NMP-IL and nickel hexacyanoferrate (NiHCF) thin film, known as the ion storage layer, was further demonstrated. The proposed NMP-IL/NiHCF ECD accomplished a large transmittance change of 56.6% at 575 nm, a desirable coloration efficiency of 166 cm2/C, and attenuated 120.9 W/m2 solar irradiance between bleached state and colored state with a minimal consumed power per unit area of 1.08 W/m2. Besides, impressive long-term stabilities of the proposed ECDs, under both room temperature (92.3% retention of its original ΔT after 10,000 cycles) and high temperature (80.2% retention of its original ΔT after 3,000 cycles at 65 °C), were achieved. These merits reveal that NMP-IL has the potential to become the new anodically coloring material for application in energy-saving ECDs. [ABSTRACT FROM AUTHOR]