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The article discusses the routine testing and reporting of piperacillin/tazobactam susceptibility in Elizabethkingia species, which are increasingly prevalent pathogens in Asia. The study found that there is variability in the results of different susceptibility assays, leading to inconsistent reporting of susceptibility rates. In addition, the presence of a specific gene, blaB, in Elizabethkingia species was found to increase resistance to piperacillin/tazobactam and reduce its efficacy in vivo. The authors suggest that routine testing and reporting of piperacillin/tazobactam susceptibility in Elizabethkingia species may not be informative for treatment decisions. [Extracted from the article]

We present a novel method for estimating species abundance using presence–absence maps. Our approach takes the spatial context into consideration, distinguishing it from conventional methods. The proposed method is built upon a well-known kernel estimation for point pattern intensity, with the addition of a new parameter representing the mean abundance in each occupied cell. The parameter estimate is obtained through maximum likelihood estimation. The expected abundance corresponds to the integral of the intensity over the study area, which can be estimated by taking the Riemann sum of the intensity. The implementation of our method is straightforward, using existing packages in the R software. We compared various bandwidth selection methods within our approach and assessed the estimation performance against some approaches based on the random placement model or negative binomial model through the simulation study and an empirical forestry data in Barro Colorado Island (BCI), Panama. The results of the simulation and the application demonstrate that our method, with a carefully chosen bandwidth, outperforms the alternatives for highly aggregated data and improves the issue of underestimation. Supplementary materials accompanying this paper appear online. [ABSTRACT FROM AUTHOR]

Before vaccines were introduced, mobility restriction was one of the primary control measures in the early stage of the coronavirus disease 2019 (COVID-19) pandemic. Because different age groups face disproportionate health risks, differences in their mobility changes affect the effectiveness of pandemic control measures. This study aimed to investigate the relationship between multiscale mobility patterns in different age groups and COVID-19 transmission before and after control measures implementation. Data on daily confirmed case numbers, anonymized mobile phone data, and 38 socioeconomic factors were used to construct negative binomial regression models of these relationships in the Taipei metropolitan area in May 2021. To avoid overfitting, the socioeconomic factor dimensions were reduced by principal component analysis. The results showed that inter-district mobility was a greater promoter of COVID-19 transmission than was intra-district mobility (coefficients: pre-alert, 0.52 and 0.43; post-alert, 0.41 and 0.36, respectively). Moreover, both the inter-district mobility of people aged 15–59 and ≥ 60 years were significantly related to the number of confirmed cases (coefficients: pre-alert, 0.82 and 1.05; post-alert, 0.48 and 0.66, respectively). The results can help agencies worldwide formulate public health responses to emerging infectious diseases. [ABSTRACT FROM AUTHOR]

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]

Before vaccines were introduced, mobility restriction was one of the primary control measures in the early stage of the coronavirus disease 2019 (COVID-19) pandemic. Because different age groups face disproportionate health risks, differences in their mobility changes affect the effectiveness of pandemic control measures. This study aimed to investigate the relationship between multiscale mobility patterns in different age groups and COVID-19 transmission before and after control measures implementation. Data on daily confirmed case numbers, anonymized mobile phone data, and 38 socioeconomic factors were used to construct negative binomial regression models of these relationships in the Taipei metropolitan area in May 2021. To avoid overfitting, the socioeconomic factor dimensions were reduced by principal component analysis. The results showed that inter-district mobility was a greater promoter of COVID-19 transmission than was intra-district mobility (coefficients: pre-alert, 0.52 and 0.43; post-alert, 0.41 and 0.36, respectively). Moreover, both the inter-district mobility of people aged 15–59 and ≥ 60 years were significantly related to the number of confirmed cases (coefficients: pre-alert, 0.82 and 1.05; post-alert, 0.48 and 0.66, respectively). The results can help agencies worldwide formulate public health responses to emerging infectious diseases. [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]

This paper presents a preliminary study on establishing a mobile point-to-point (P2P) microwave air-bridging (MAB) between Unmanned Low Altitude Flying Platform (ULAFP) and backhaul telecommunication network. The proposed Sky-Net system relays telecom signal for general mobile cellphone users via ULAFP when natural disaster sweeps off Base Transceiver Stations (BTSs). Unlike the conventional fix point microwave bridging application, the ULAFP is cruising on a predefined mission flight path to cover a wider range of service. The difficulty and challenge fall on how to maintain antenna alignment accurately in order to provide the signal strength for MAB. A dual-axis rotation mechanism with embedded controller is designed and implemented on airborne and ground units for stabilizing airborne antenna and tracking the moving ULAFP. The MAB link is established in flight tests using the proposed antenna stabilizing/tracking mechanism with correlated control method. The result supports backbone technique of the Sky-Net mobile communication and verifies the feasibility of airborne e-Cell BTS. [ABSTRACT FROM AUTHOR]

ABSTRACT A diamine containing heterocyclic pyridine and unsymmetrical carbazole substituents, 4-(9-ethyl-3-carbazole)-2,6-bis(4-aminophenyl)pyridine ( CBAPP), was prepared for use in the synthesis of poly(pyridine-imide)s PI-1-8 by direct polycondensation with dianhydrides in N,N-dimethylacetamide (DMAc). The poly(pyridine-imide)s derived from the diamine are highly soluble in solvents such as N-Methyl-2-pyrrolidone (NMP) and DMAc at room temperature. Noncoplanar polyimide (PI-1) showed excellent solubility, high transparency, and high-performance mechanical properties. These polymers had relatively high glass transition temperatures and exhibited good thermal stability in both nitrogen ( Td10 > 470 °C) and air ( Td10 > 450 °C). The PI-3∼5 cannot form flexible and tough films due to the unsymmetrical carbazole moiety, rigid structure, and polar-polar interaction. However, through copolymerization technique these polymers (PI-6∼8) could be enhanced through the solubility, mechanical, and thermal properties. The optical properties included a strong orange fluorescence (540 nm) after protonation with acid. When the HCl concentration was increased, a new absorption band at approximately 350 nm appeared, and the intensity of the fluorescent peak at 380 nm observed in the neutral polymer solution decreased, along with the appearance of the new fluorescent peak at 540 nm. The poly(pyridine-imide)s presented here showed only slight fluorescence quenching in the presence of methanol. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 405-412 [ABSTRACT FROM AUTHOR]

A new diamine containing pyridineand carbazole groups was synthesizedvia a Chichibabin reaction and subsequent reduction; this compoundwas then used in the preparation of organo-soluble aramides (PA-a–i). The resultant polymers had high glass transitiontemperatures, which fell within the ranges of 271–287 °C,and Td10at 510–535 °C ina nitrogen atmosphere. The pristine PA-aexhibited themaximum value in the UV–vis absorption spectrum at 307 nm,and this value shifted to 394 nm after protonation by HCl. When theemission of the polymer in THF solution was observed, the intensityof the emission peak at 420 nm decreased and the intensity of a newemission peak at 552 nm increased as the acid concentration increased.Additionally, the color of the polymer solution changed from blueto yellow after protonation. The intensity of the emission at 552nm based on excimers increased as MeOH content increased. The colorof polymer films also changed irreversibly from yellow, which wasindicative of the neutral form, to a dark brown oxidized form duringthe application of bias voltages ranging from 0 to 1.6 V. [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]

Novel polynorbornenes, poly(NBPYTPA), and poly(HNBPYTPA), containing chromophoric and electroactive groups were synthesized by ring-opening metathesis polymerization using Grubbs' catalysts and followed hydrogenation, respectively. The glass transition temperatures ( Tg) of poly(NBPYTPA) and hydrogenated poly(HNBPYTPA) were 195 and 165 °C, respectively. The 10% weight-loss temperatures of hydrogenated poly(HNBPYTPA) and poly(NBPYTPA) were up to 465 and 420 °C, respectively. The photoluminescence emission spectra of poly(HNBPYTPA) showed strong solvatochromic property, revealing that poly(HNBPYTPA) underwent remarkable bathochromic shifts with an increase in solvent polarity. The cyclic voltammogram of poly(HNBPYTPA) film cast onto an indium tin oxide (ITO)-coated glass substrate exhibited two reversible oxidation redox couples at 0.8 and 1.2 V versus Ag/Ag+ in acetonitrile solution. The electrochromic characteristics of poly(HNBPYTPA) showed reversibility, with color changes from yellow to blue and then to red upon the application of potentials from 0 to 1.3 V. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 000: 000-000, 2011 [ABSTRACT FROM AUTHOR]

• 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]

A new diiodo monomer containing heterocyclic pyridine and carbazole groups was synthesized via Chichibabin reaction and used in the preparation of a conjugated polymer via Suzuki coupling approach. The conjugated polymer was highly soluble in common organic solvents such as NMP, THF, dichloromethane, chloroform, toluene, xylene, and benzene at room temperature. The polymer had high glass transition temperature at 191 °C and Td10 at 434 °C in nitrogen atmosphere. The pristine polymer exhibited the UV–vis maximum absorption at 355 nm and shifted to 420 nm after protonation. The emission of the polymer in THF solution changed from the blue region with maximum peak at 400 nm to the yellow region with maximum peak at 540 nm after protonated by HCl, and the intensity of emission depended on the concentration of acid. The polymer also showed electrochromic behavior under applied voltage. The emission color of the polymer film changed from blue (435 nm) to yellow (570 nm) when 2.5 V bias voltage was applied. The polymer also exhibited write‐once and read‐many‐times (WORM) polymer memory effect with tristable states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 991–1002, 2009 [ABSTRACT FROM AUTHOR]

[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]

We investigate the effect of a high hole mobility triarylamine-based conjugated polymer on a bulk hetero-junction organic solar cell. We employed a polymer blend consisting of poly(3-hexylthiophene) (P3HT), [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), and poly(N-(4 -(9,9-dioctyl-fluoren-2-yl)phenyl)-N,N′,N′-triphenyl-l,4-phenylenediamine) (PFLAM) as active materials. The hole mobility of PFLAM is ∼10-3 cm2 V-1 s-1, which is similar to the electron mobility of PCBM. Addition of PFLAM improves the hole mobility of the photovoltaic cell augmenting the charge balance of the system. The overall efficiency gain for such a device is 34%. [ABSTRACT FROM AUTHOR]

A new root canal sealer was developed based on urethane acrylates using polycarbonate polyol (PCPO), a macrodiol prepared in the consumption of carbon dioxide as feedstock. The superior mechanical properties and biostability nature of PCPO-based urethane acrylates were then co-crosslinked with a difunctional monomer of tripropylene glycol diarylate (TPGDA) as sealers for resin matrix. Moreover, nanoscale silicate platelets (NSPs) immobilized with silver nanoparticles (AgNPs) and/or zinc oxide nanoparticles (ZnONPs) were introduced to enhance the antibacterial effect for the sealers. The biocompatibility and the antibacterial effect were investigated by Alamar blue assay and LDH assay. In addition, the antibacterial efficiency was performed by using Enterococcus faecalis (E. faecalis) as microbial response evaluation. These results demonstrate that the PCPO-based urethane acrylates with 50 ppm of both AgNP and ZnONP immobilized on silicate platelets, i.e., Ag/ZnO@NSP, exhibited great potential as an antibacterial composite for the sealer of root canal obturation. [ABSTRACT FROM AUTHOR]

Background The emergence of mobile colistin resistance gene mcr-1 , a plasmid-borne polymyxin resistance mechanism, in carbapenem-resistant Klebsiella pneumoniae is an alarming concern. However, previous studies showed that the acquisition of mcr-1 was associated with a significant biological fitness cost in K. pneumoniae. We aimed to study the impact of mcr-1 on the biological fitness in clinical carbapenemase-producing K. pneumoniae strains. Methods Clinical carbapenemase-producing K. pneumoniae strains were collected consecutively at the Taipei Veterans General Hospital between November 2017 and December 2018. The strain positive for mcr-1 was subjected to whole-genome sequencing to delineate its genomic features. Escherichia coli J53 strain was used as the recipient strain in plasmid conjugation assay and the transconjugants were selected with sodium azide and colistin. Plasmid stability was tested by serial passaging in antibiotic-free LB broth for 28 days. The growth rate was compared between the parental mcr-1 -bearing strain and the plasmid-cured strain. Results One ST11 strain isolated from a fatal case with bacteremia (KP2509) was found to harbor bla KPC-2, bla OXA-48, and mcr-1. This strain was resistant to colistin (MIC=8 mg/L) and imipenem (MIC≥16 mg/L). Whole-genome sequencing of KP2509 showed that mcr-1 , bla KPC-2 and bla OXA-48 were located on an IncHI-FIB type plasmid of 319 Kb, an IncFII type plasmid of 96 Kb, and an IncL type plasmid of 64 Kb, respectively. Conjugation efficiency of mcr-1 -bearing plasmid was 2.24 × 10–4, and the colistin MIC of E. coli J53 transconjugant increased from 0.5 to 8 mg/L. The mcr-1 -bearing plasmid in KP2509 showed high plasmid stability, and only ~1% were lost after 27-day passages. The resulting plasmid-cured strain (PC-KP2509) was susceptible to colistin (MIC=0.5 mg/L) and had a similar growth rate to that of parental mcr-1 -bearing strain KP2509. Conclusion We identified an ST11 K. pneumoniae strain carrying bla KPC-2, bla OXA-48, and mcr-1 genes causing a fatal bacteremia. The large mcr-1 -bearing plasmid confers a moderate level of colistin resistance but without significant biological fitness cost in carbapenemase-producing K. pneumoniae , which could result in a serious threat clinically. Disclosures All authors: No reported disclosures. [ABSTRACT FROM AUTHOR]