pinecone/core-2020-05-10-deduplication huggingface dataset:
Antecedents of retweeting in a (political) marketing context

Word of mouth disseminates across Twitter by means of retweeting; however the antecedents of retweeting have not received much attention. This study uses the CHAID decision tree predictive method (Kass, 1980) with readily available Twitter data, and manually coded sentiment and content data, to identify why some tweets are more likely to be retweeted than others in a (political) marketing context. The analysis includes four CHAID models: (i) using message structure variables only, (ii) source variables only, (iii) message content and sentiment variables only and (iv) a combined model using source, message structure, message content and sentiment variables. The aggregated predictive model correctly classified retweeting behavior with a 76.7% success rate. Retweeting tends to occur when the originator has a high number of Twitter followers and the sentiment of the tweet is negative, contradicting previous research (East, Hammond, & Wright, 2007; Wu, 2013) but concurring with others (Hennig-Thurau, Wiertz, & Feldhaus, 2014). Additionally, particular types of tweet content are associated with high levels of retweeting, in particular those tweets including fear appeals or expressing support for others, whilst others are associated with very low levels of retweeting, such as those mentioning the sender’s personal life. Managerial implications and research directions are presented. The study makes a methodological contribution by illustrating how CHAID predictive modelling can be used for Twitter data analysis and a theoretical contribution by providing insights into why retweeting occurs in a (political) marketing context
Interpreting Social Identity in Online Brand Communities: Considering Posters and Lurkers

YesThis study investigates the psychological effects of social identity on both posters and lurkers in online brand communities (OBCs). The results reveal the intermediate mechanisms mediating and moderating members’ social identity effects on members’ brand commitment leading to positive word-of-mouth and their resistance to negative information about the brand. This article treats social identity as a multi-dimensional construct. Differences amongst posters and lurkers on the relationships between the cognitive, affective and evaluative components of social identity are investigated along with their positive effect on brand commitment and behavioral consequences. Using a sample of 752 OBC members, both posters and lurkers emerge as valuable members and equally likely to derive social identity from their membership of an OBC. However, there are counter intuitive results for relationships within the research model between active and passive members of OBCs. These results offer implications for theory and can help managers to be better interactive marketers
Toward a framework for identifying attitudes and intentions to music acquisition from legal and illegal channels

Technological developments have had a profound effect on modern music acquisition, allowing people to share music over the Internet for free. The research identifies the antecedents of consumers’ attitudes and intentions to acquire music from various channels. The paper reports findings of a structured questionnaire survey of university students in the United Kingdom and Greece (n = 511). Using structural equation modeling, the authors conclude that consumers’ intention to acquire music via a legal channel is influenced by idolatry (IDL), the perceived quality of music (PQM), the perceived likelihood of punishment (PLP; digital legal channel only), and their subjective norm. On the other hand, intention to acquire music via an illegal channel is influenced by the perceived benefits of piracy. The price of legitimate music was only significant for the illegal street vendor channel, whereas IDL had a positive effect on illegal downloading. Gender had moderating effects on PLP and attitude, and income-moderated attitude and intention from P2P platforms. The findings carry important implications for academic researchers, practitioners, and policymakers
Consumer revenge using the Internet and social media : an examination of the role of service failure types and cognitive appraisal processes.

Given the pervasive spread and use of the Internet and social media, consumer use of these new forums for expressing their revenge intentions has also increased. This research examines the impacts of service outcome and service process failures on consumer online revenge intentions. Using insights from cognitive appraisal theory, a comprehensive model is developed and tested to examine the impacts of service failure types on consumers’ primary and secondary appraisal processes that lead to online revenge intentions. The model was tested in the United Kingdom and Jordan. Results show that for the two countries, different service failure types lead to different cognitive appraisal processes, and to intentions to use different online revenge platforms
PMMA/zinc oxide nanocomposites prepared by in-situ bulk polymerization

Dispersing surface-modified zinc oxide nano-particles (ZnO) in methyl methacrylate (MMA) improves the free radical bulk polymerization process as well as the thermal stability of the formed polymer. Hydroxy groups available on the ZnO surface may induce a degenerative transfer. This suppresses the gel effect, which leads to a better control of the heat evolution during the late stages of polymerization. The formation of chains having vinylidene end groups and head-to-head links is suppressed, which shifts the onset of thermal decomposition to the regime where decomposition occurs by random chain scission
Squishy Non-Spherical Hydrogel Microparticles

Recent advances in the synthesis of polymeric colloids have opened the doors to new advanced materials. There is strong interest in using these new techniques to produce particles that mimic and/or interact with biological systems. An important characteristic of biological systems that has not yet been exploited in synthetic polymeric colloids is their wide range of deformability. A canonical example of this is the human red blood cell (RBC) which exhibits extreme reversible deformability under flow. Here we report the synthesis of soft polymeric colloids with sizes and shapes that mimic those of the RBC. Additionally, we demonstrate that the mechanical flexibility of the colloids can be reproducibly varied over a large range resulting in RBC-like deformability under physiological flow conditions. These materials have the potential to impact the interaction between biological and synthetic systems.available in PMC 2011 July 15Massachusetts Institute of Technology (MIT-MGH Fellowship in Translational Research)Massachusetts General Hospital (MIT-MGH Fellowship in Translational Research)National Institute of Biomedical Imaging and Bioengineering (U.S.) (BioMEMS Resource Center, P41 EB002503)John Simon Guggenheim Memorial FoundationInstitut Curie (Rothschild-Yvette-Mayent-Institute Curie Fellowship
A nanotechnology pathway to arresting phase separation in soft nanocomposites

6 páginas, 3 figuras.Direct observation of the miscibility improving effect of ultra-small polymeric nanoparticles (radius ≈4 nm) in model systems of soft nanocomposites is reported. We have found thermodynamically arrested phase separation in classical poly(styrene) (PS)/poly(vinyl methyl ether) blends when PS linear chains were totally replaced by ultra-small, single chain PS nanoparticles, as determined by thermo-optical microscopy measurements. Partial arrested phase splitting on heating was observed when only some of the PS chains were replaced by unimolecular PS nanoparticles, leading to a significant increase of the lower critical solution temperature (LCST) of the system (up to 40 °C at 15 vol.-% nanoparticle content). Atomic force microscopy and rheological experiments supported these findings. Thermodynamic arrest of the phase separation process induced by replacement of linear polymer chains by unimolecular polymer nanoparticles could have significant implications for industrial applications requiring soft nanocomposite materials with excellent nanoparticle dispersion in a broad temperature range.This work was supported by MEC (CIC NANOGUNE-CONSOLIDER Grant No. CSD2006-53) and Basque\ud
Government (INANOGUNE Project).Peer reviewe
Conjugation of siRNA with comb-type PEG enhances serum stability and gene silencing efficiency

A thiol-modified siRNA targeting the enhanced green fluorescence protein (eGFP) gene was conjugated with RAFT-synthesized, pyridyl disulfide-functional poly(PEG methyl ether acrylate)s (p(PEGA)s). siRNA-p(PEGA) conjugates demonstrated significantly enhanced in vitro serum stability and nuclease resistance compared to the unmodified and thiol-modified siRNA. The complexes of siRNA-p(PEGA) conjugates with a fusogenic peptide, KALA ((+)/(-) = 2) inhibited the protein expression approximately 28-fold more than the KALA complex of the unmodified siRNA. The protein inhibition caused by siRNA-p(PEGA)-KALA complexes (56± 5%-58± 3% of the fluorescence expressed in non-treated cells) was comparable to the effect of the unmodified siRNA-lipofectamine complex (77± 7%)
Is the Reduction in Tracer Diffusivity under Nanoscopic Confinement Related to a Frustrated Segmental Mobility?

We developed an experimental method for the determination of the tracer diffusivity D-tr in ultrathin polymer films, and the changes in the segmental mobility of tracer molecules while they diffuse through matrices of different thickness and get adsorbed onto a target substrate. D-tr starts decreasing already at 120-150 nm and drops to 1% of its bulk value in films as thin as 7.5 nm. We discuss the results highlighting a strong decoupling between the reduction in mass transport at the nanoscale and the increase in the glass transition temperature determined via capacitive dilatometry together with a breakdown of the Stokes-Einstein relation between orientational and translational degrees of freedom.status: publishe
Synthesis of β‐Cyclodextrin Containing Copolymer via “Click” Chemistry and Its Self‐Assembly in the Presence of Guest Compounds

We report the synthesis of a hydrophilic copolymer with one polyethylene glycol (PEG) block and one β‐cyclodextrin (β‐CD) containing block by a “click” reaction between azido‐substituted β‐CD and propargyl flanking copolymer.  1 H NMR study suggested a highly efficient conjugation of β‐CD units by this approach. The obtained copolymer was used as a host macromolecule to construct assemblies in the presence of hydrophobic guests. For assemblies containing a hydrophobic polymer, their size can be simply adjusted by simply changing the content of hydrophobic component. By serving as a guest molecule, hydrophobic drugs can also be loaded accompanying the formation of nanoparticles, and the drug payload is releasable. Therefore, the copolymer synthesized herein can be employed as a carrier for drug delivery.     The synthesis of β‐cyclodextrin containing block copolymer via a “click” reaction  is reported. The self‐assembly of this newly synthesized copolymer in the presence of guest compounds can lead to the formation of core–shell structured nanoparticles. These assemblies can be employed as novel delivery vehicles for therapeutics
Bio‐Orthogonal Polymer Coatings for Co‐Presentation of Biomolecules

Controlled presentation of biomolecules on synthetic substrates is an important aspect for biomaterials development. If the immobilization of multiple biomolecules is required, highly efficient orthogonal surface chemistries are needed to ensure the precision of the immobilization. In this communication, chemical vapor deposition (CVD) copolymerization is used to fabricate polymer coatings with controlled ratio of alkyne and pentafluorophenyl ester (Pfp‐ester) groups. Cyclic argine‐glycine‐aspartic acid (cRGD) adhesion peptide and epidermal growth factor (EGF) are immobilized through alkyne–azide cycloaddtion (“click” chemistry) and active ester–amine reaction, respectively. Cell studies with human umbilical vein endothelial cells (HUVEC) and A431 cell lines demonstrate the biological activity of the coimmobilized biomolecules.     Polymer coatings with bio‐orthogonal functional groups are developed for co‐immobilization  of adhesion peptide and growth factor. The coatings are generated by chemical vapor deposition polymerization, with both alkyne and pentafluorophenyl ester which are used to covalently tether the biomolecules. The biological activity of the co‐immobilized biomolecules is demonstrated
Polydiacetylene Liposome Microarray Toward Influenza A Virus Detection: Effect of Target Size on Turn‐On Signaling

Target size effect on the sensory signaling intensity of polydiacetylene (PDA) liposome microarrays was systematically investigated. Influenza A virus M1 peptide and M1 antibody were selected as a probe–target pair. While red fluorescence from the PDA liposome microarrays was observed when the larger M1 antibody was used as a target, when the same M1 antibody was used as a probe to detect the smaller M1 peptide sensory signal did not appear. The results reveal that the intensity of the PDA sensory signal is mainly related to the steric repulsion between probe–target complexes not the strength of the probe–target binding force. Based on this finding, we devised a PDA sensory system that directly detects influenza A whole virus as a larger target, and confirmed the target size effect on the signaling efficiency of PDA.             The 2009 influenza pandemic  highlighted the need for a rapid and sensitive influenza A virus detection kit. A systematically investigated polydiacetylene microarray sensor allows a turn‐on sensory signal within 1 h and comparable detection limit with conventional kits. Denser probe molecules and larger targets contribute to PDA sensitivity, providing insight for designing future PDA‐based sensors
Synthesis and on-demand gelation of multifunctional poly(ethylene glycol)-based polymers

The synthesis of a novel photoreactive poly(ethylene glycol) (PEG)-based polymer with caged carbonyl groups is reported. We further demonstrate its use for the on-demand fabrication of hydrogels. For rapid gelation, a hydrazide-functionalized PEG is used as the second component for the hydrogel preparation. The photoreactive PEG-based polymer is designed for controlled cleavage of the protecting groups upon exposure to UV light releases free aldehyde moieties, which readily react with hydrazide groups in situ. This hydrogel system may find applications in controlled release drug delivery applications, when combined with in situ gelation. Furthermore, the possibility of forming gels specifically upon UV irradiation gives an opportunity for 3D fabrication of degradable scaffolds
Balancing the Initiation and Molecular Recognition Capabilities of Eosin Macroinitiators of Polymerization-Based Signal Amplification Reactions

Coupling polymerization initiators to molecular recognition events provide the ability to amplify these events and detect them using the formation of a cross-linked polymer as an inexpensive readout that is visible to the unaided eye. The eosin-tertiary amine co-initiation system, activated by visible light, has proven utility in this context when an average of three eosin molecules are coupled to a protein detection reagent. The present work addresses the question of how detection sensitivity is impacted when the number of eosin molecules per binding event increases in the range of two to fifteen. Unlike in other initiation systems, a non-monotonic relationship is observed between the number of initiators per binding event and the observed detection sensitivity.Burroughs Wellcome Fund (Career Award at the Scientific Interface)Massachusetts Institute of Technology. James H. Ferry Fund for Innovation in Research Educatio
Boron-ketoiminate-based polymers: fine-tuning of the emission color and expression of strong emission both in the solution and film States.

In this research, the synthesis of boron-ketoiminate-containing polymers is reported with large molecular weights ([Mn] = 20 000) and their optical properties are examined by UV-vis absorption and photoluminescence spectrometries. It is shown that the polymers exhibit strong emission both in the solution and solid states (Φ [PL, THF] = 0.46-0.80, Φ [PL, film] = 0.13-0.38). These optical properties can be explained by a donor-acceptor interaction between the boron ketoiminate and the electron-donating comonomer such as fluorene or bithiophene. Furthermore, in the solid states, their emission colors can be successfully tuned from blue to orange by the substituents on the nitrogen atom with the difference of the steric hindrance (λ [PL, THF] = 464-546 nm, λ [PL, film] = 486-604 nm)
Solvent vapor annealing of block copolymers in confined topographies: commensurability considerations for nanolithography

The directed self-assembly of block copolymer (BCP) materials in topographically patterned substrates (i.e., graphoepitaxy) is a potential methodology for the continued scaling of nanoelectronic device technologies. In this Communication, an unusual feature size variation in BCP nanodomains under confi nement with graphoepitaxially aligned cylinder-forming poly(styrene)- block -poly(4-vinylpyridine) (PS- b -P4VP) BCP is reported. Graphoepitaxy of PS- b -P4VP BCP line patterns (C II ) is accomplished via topography in hydrogen silsequioxane (HSQ) modified substrates and solvent vapor annealing (SVA). Interestingly, reduced domain sizes in features close to the HSQ guiding features are observed. The feature size reduction is evident after inclusion of alumina into the P4VP domains followed by pattern transfer to the silicon substrate. It is suggested that this nanodomain size perturbation is due to solvent swelling effects during SVA. It is proposed that using a commensurability\ud
value close to the solvent vapor annealed periodicity will alleviate this issue leading to uniform nanofins
Synthesis of a platinum diketonate-containing polymer showing oxygen-resistant phosphorescence.

The synthesis of a platinum diketonate-based alternating copolymer containing a fluorene unit and its oxygen-resistant phosphorescence are reported. The polymerization is executed via palladium-catalyzed Suzuki-Miyaura coupling reaction. The synthesized polymer shows good solubility in common organic solvents and processability to form homogeneous films. By optical measurements it is found that the synthesized polymer shows phosphorescence from a triplet π-π* ligand-centered transition, and interestingly, the emission is hardly influenced by oxygen. Phosphorescence is observed from both solution and film samples under aerobic conditions. The new idea of obtaining emissive materials based on conjugated polymers showing oxygen-resistant phosphorescence is presented here
Toward Hybrid Materials: Group Transfer Polymerization of 3-(Trimethoxysilyl)propyl Methacrylate

Front Cover: Group transfer polymerisation (GTP), a living polymerization technique that is easy to scale up, enables the one-pot fabrication of class-II hybrid materials. Specifically a star polymer is synthesized with a 3-(trimethoxy-silyl)propyl methacrylate, alkoxysilane group containing functional monomer. The polymer is then cross-linked to produce an organic-inorganic class-II hybrid material, which can be used in various applications such as thin films and biomaterials. Further details can be found in the article by J. J. Chung, J. R. Jones, and T. K. Georgiou* on page 1806
Specular and diffuse reflectance of phase-separated polymer blend films

Diffuse reflectors have various applications in devices ranging from liquid crystal displays to light emitting diodes, to coatings. Herein, specular and diffuse reflectance from controlled phase separation of polymer blend films, a well-known self-organization process, are studied. Temperature-induced spinodal phase separation of polymer blend films in which one of the components is selectively extracted is shown to exhibit enhanced surface roughness as compared to unextracted films, leading to a notable increase of diffuse reflectance. Diffuse reflectance of UV-visible light from such selectively leached phase-separated blend films is determined by a synergy of varying lateral scale of phase separation (approximate to 200 nm to 1 mu m) and blend film surface roughness (0-40 nm). These critical parameters are controlled by tuning annealing time (0.5-3 h) and temperature (140, 150, 160 degrees C) of phase separation. Angle-resolved diffuse reflection studies show that the surface-roughened polymer films exhibit diffuse reflectance up to 40 degrees from normal incident light in contrast to optically uniform as-cast films that exhibit largely specular reflectance. Furthermore, the intensity of the diffusively reflected light can be enhanced (300-700 nm) or reduced (220-300 nm) significantly by coating the leached phase-separated films with a thin silver over layer
Distinct Interfacial Fluorescence in Oil-in-Water Emulsions via Exciton Migration of Conjugated Polymers

Commercial dyes are extensively utilized to stain specific phases for the visualization applications in emulsions and bioimaging. In general, dyes emit only one specific fluorescence signal and thus, in order to stain various phases and/or interfaces, one needs to incorporate multiple dyes and carefully consider their compatibility to avoid undesirable interactions with each other and with the components in the system. Herein, surfactant‐type, perylene‐endcapped fluorescent conjugated polymers that exhibit two different emissions are reported, which are cyan in water and red at oil–water interfaces. The interfacially distinct red emission results from enhanced exciton migration from the higher‐bandgap polymer backbone to the lower‐bandgap perylene endgroup. The confocal microscopy images exhibit the localized red emission exclusively from the circumference of oil droplets. This exciton migration and dual fluorescence of the polymers in different physical environments can provide a new concept of visualization methods in many amphiphilic colloidal systems and bioimaging.National Science Foundation (U.S.) (National Science Foundation DMR‐1410718
Segmental mobility studies of poly(N-isopropyl acrylamide) interactions with gold nanoparticles and its use as a thermally driven trapping system

YesThermal desolvation of poly(N‐isopropylacrylamide) (PNIPAM) in the presence of a low concentration of gold nanoparticles incorporates the nanoparticles resulting in suspended aggregates. By covalently incorporating <1% acenaphthylene into the polymerization feed this copolymer is enabled to be used as a model to study the segmental mobility of the PNIPAM backbone in response to gold nanoparticles both below and above the desolvation temperature, showing that there is a physical conformational rearrangement of the soluble polymer at ultralow nanoparticle loadings, indicating low affinity interactions with the nanoparticles. Thermal desolvation is capable of extracting >99.9% of the nanoparticles from their solutions and hence demonstrates that poly(N‐isopropylacrylamide) can act as an excellent scrubbing system to remove metallic nanomaterial pollutants from solution.Science Foundation Ireland's ETS. Grant Number: 11/W.I/12085; MRC. Grant Number: MR/N501888/