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Myeloperoxidase (MPO) is one of the most abundant proteins in neutrophil granules. It catalyzes the production of reactive oxygen species, which are important in inflammation and immune defense. MPO also binds to several proteins, lipids, and DNA to alter their function. MPO is present at the feto-maternal interface during pregnancy, where neutrophils are abundant. In this study, we determined the effect of MPO on JEG-3 human choriocarcinoma cells as a model of extravillous trophoblasts (EVTs) during early pregnancy. We found that MPO was internalized by JEG-3 cells and localized to the cytoplasm and nuclei. MPO internalization and activity enhanced JEG-3 cell migration and invasion, whereas this effect was impaired by pre-treating cells with heparin, to block cellular uptake, and MPO-activity inhibitor 4-ABAH. This study identifies a novel mechanism for the effect of MPO on EVT function during normal pregnancy and suggests a potential role of MPO in abnormal pregnancies.

Non-woven flax fibre reinforced acrylic-based polyester (NFA) composites were prepared using an impregnation process. A mixture of acrylic-based polyester (Acrodur®) with varying sodium silicate (SS) loadings was applied to impregnate the non-woven flax fibre mat. Flexural tests were performed to evaluate the mechanical properties of the composites. Flammability properties were assessed via UL94 test and limiting oxygen index (LOI). The mechanical properties of NFA composites decreased substantially with increment in SS loading. The addition of SS resulted in significant improvement of flame retardancy, whereby UL94 rating enhanced from V-1 to V-0, while the LOI values increased from 24 to 40. Sound absorption coefficients of the NFA composites were measured via two-microphone transfer function technique in impedance tube. The sound absorption properties of NFA composites also improved with the incorporation of SS, whereby the sound absorption coefficient increased up to 0.87 at 2000 Hz frequency. Based on the overall evaluation, 20 wt% of SS effectively increased flame retardancy and sound absorption properties, along with moderate deterioration in flexural properties. The scanning electron microscopic (SEM) analysis of the composites surfaces displayed formation of voids and irregular structures at higher SS loading, which reduced the mechanical properties of NFA composites. The SEM images offered supportive evidences on the role of hollow lumen structures in natural fibres to ensure better sound absorption performance in NFA composites.

In north-western Tibet (34.0° N, 82.2° E) near lake Aru Co, the entire ablation areas of two glaciers (Aru-1 and Aru-2) suddenly collapsed on 17 July and 21 September 2016. The masses transformed into ice avalanches with volumes of 68 and 83×106 m3 and ran out up to 7 km in horizontal distance, killing nine people. The only similar event currently documented is the 130×106 m3 Kolka Glacier rock and ice avalanche of 2002 (Caucasus Mountains). Using climatic reanalysis, remote sensing, and three-dimensional thermo-mechanical modelling, we reconstructed the Aru glaciers' thermal regimes, thicknesses, velocities, basal shear stresses, and ice damage prior to the collapse in detail. Thereby, we highlight the potential of using emergence velocities to constrain basal friction in mountain glacier models. We show that the frictional change leading to the Aru collapses occurred in the temperate areas of the polythermal glaciers and is not related to a rapid thawing of cold-based ice. The two glaciers experienced a similar stress transfer from predominant basal drag towards predominant lateral shearing in the detachment areas and during the 5–6 years before the collapses. A high-friction patch is found under the Aru-2 glacier tongue, but not under the Aru-1 glacier. This difference led to disparate behaviour of both glaciers, making the development of the instability more visible for the Aru-1 glacier through enhanced crevassing and terminus advance over a longer period. In comparison, these signs were observable only over a few days to weeks (crevasses) or were absent (advance) for the Aru-2 glacier. Field investigations reveal that those two glaciers were underlain by soft, highly erodible, and fine-grained sedimentary lithologies. We propose that the specific bedrock lithology played a key role in the two Tibet and the Caucasus Mountains giant glacier collapses documented to date by producing low bed roughness and large amounts of till, rich in clay and silt with a low friction angle. The twin 2016 Aru collapses would thus have been driven by a failing basal substrate linked to increasing pore water pressure in the subglacial drainage system in response to increases in surface melting and rain during the 5–6 years preceding the collapse dates.

Poly(lactic acid) (PLA) synthesized from renewable resources has drawn a great deal of interest in packaging, electronics and automotive applications. However, poor flame retardancy of PLA, especially its ease of ignitability and heavily flaming drips, represents a major obstacle for its potential application. The article outlines the recent advances in the field of flame-retarded PLA. Current development trends based on the direct incorporation of flame retardant additives, chemical modification, hybridization and synthesis of flame retardants were reported. Results obtained from UL 94 vertical burning, limiting oxygen index (LOI) and cone calorimetry (CCM) tests for each type of flame retardants were discussed and analyzed. Test results summarized in a UL 94-LOI matrix found to be a useful tool to determine the effectiveness of flame retardants in PLA. The UL 94-LOI comparison matrix and CCM test results revealed that the combined use of flame retardants (containing intumescent formulation) is one of the promising strategies to reach the flame retardancy of PLA needed by practical applications. This review ends with a brief summary of and outlook on future developments of flameretarded PLA systems.

The article presents a study which examines the sports fans' interest in overseas football/soccer leagues and clubs and its role in the development of an Australian national soccer league named A-League. The study has conducted three surveys over a two-year period with an approximately 3,700 season ticket holders. Results show that sports fans' interest on the overseas clubs confirmed to be a major antecedent of interest in the A-League.

We introduced a general concept to create smart, (multi)functional interphases in polymer composites with layered reinforcements, making use of 3D printing. The concept can be adapted for both thermoplastic and thermoset matrix-based composites with either thermoplastic- or thermoset-enriched interphases. We showed feasibility using an example of a composite containing a thermoset matrix/thermoplastic interphase. Carbon fiber unidirectional reinforcing layers were patterned with poly(ε-caprolactone) (PCL) through 3D printing, then infiltrated with an amine-cured epoxy (EP). The corresponding composites were subjected to static and dynamic flexure tests. The PCL-rich interphase markedly improved the ductility in static tests without deteriorating the flexural properties. Its effect was marginal in Charpy impact tests, which can be explained with effects of specimen and PCL pattern sizes. The PCL-rich interphase ensured self-healing when triggered by heat treatment above the melting temperature of PCL.

Different regions of Infra-Red (IR) light absorption by guest molecules inside a zeolitic crystal are measured and quantified to determine binary adsorption isotherms and transport diffusivities. This has been achieved using a vacuum capable setup which includes an Infra-Red Microscope (IRM) and Fourier Transform Infra-Red (FTIR) Spectrometer. By utilizing IR light and FTIR spectroscopy, this method can be used to describe the behavior of low concentrations of relatively fast molecules inside zeolitic crystals as an alternative to chromatographic pulse methods. To demonstrate the capabilities of this method, binary adsorption isotherms and transport diffusivities of CO2 in mixtures composed of CO2 and N2 inside silicalite have been determined. From the fundamental measurements determined using this method, complex gas separation processes such as swing adsorption and multi stage membrane systems can be designed for novel zeolite materials. This method can also be used to develop models for complex adsorption and diffusion systems, and validate sophisticated molecular simulation models. • IR microimaging with static gas dosing system for measuring transient uptake, diffusion and chemical reactions of gases and their mixtures in individual crystals or particles of nanoporous materials • Using giant crystals the setup allows to study adsorption and transport of single components and mixtures in nanoporous materials also for fast diffusing guest molecules

Segmented linear polyurethanes (PUs) containing Diels-Alder (DA) adduct were synthesized in toluene solution from poly(ε-caprolactone) (PCL, Mn = 10, 25 and 50 kg/mol), diisocyanate (methylene diphenyl diisocyanate (MDI), 2,4-toluene diisocyanate (TDI), 1,6-hexamethylenediisocyanate, (HDI)), furfurylamine (FA) and bismaleimide (BMI). The order of the segments in the PUs was -PCL-MDI-FA-BMI-. The PUs were characterized by size-exclusion chromatography (SEC), different spectroscopic (1H-NMR, attenuated total reflectance Fourier-transform infrared, AT-FTIR), thermal and mechanical analysis (differential scanning calorimetry, DSC, dynamical mechanical analysis, DMA). The DA and retro-DA reactions were identified by 1H-NMR for both the synthesized PU and the coupling components (i.e. FA and BMI). Tensile mechanical and shape memory (SM) properties of the PUs were also determined. The DA coupling in the PU was improved by heat treatment above the melting temperature (Tm) of PCL. DMA traces showed a plateau-like region above Tm of PCL confirming the presence of a physical network the netpoints of which are given by the hard segments including the DA couplers. This feature suggested good SM behavior that was confirmed both qualitatively and quantitatively.

Shape memory polymers (SMPs) are capable of memorizing one or more temporary shapes and recovering to the permanent shape upon an external stimulus that is usually heat. Biodegradable polymers are an emerging family within the SMPs. This minireview delivers an overlook on actual concepts of molecular and supramolecular architectures which are followed to tailor the shape memory (SM) properties of biodegradable polyesters. Because the underlying switching mechanisms of SM actions is either related to the glass transition (Tg) or melting temperatures (Tm), the related SMPs are classified as Tg- or Tm-activated ones. For fixing of the permanent shape various physical and chemical networks serve, which were also introduced and discussed. Beside of the structure developments in one-way, also those in two-way SM polyesters were considered. Adjustment of the switching temperature to that of the human body, acceleration of the shape recovery, enhancement of the recovery stress, controlled degradation, and recycling aspects were concluded as main targets for the future development of SM systems with biodegradable polyesters.

Aim of the present study is to investigate how synthetic boehmite alumina (BA) nanoparticles modify the viscoleastic and fracture behaviour of linear low-density polyethylene. Nanocomposites containing up to 8 wt% of untreated and octyl silane-functionalized BA nanoparticles, were prepared by melt compounding and hot pressing. The BA nanoparticles were finely and unformly dispersed within the matrix according to scanning electron microscopy inspection. The results of quasi-static tensile tests indicated that nanoparticles can provide a remarkable stiffening effect at a rather low filler content. Short term creep tests showed that creep stability was significatively improved by nanofiller incorporation. Concurrently, both storage and loss moduli were enhanced in all nanocomposites, showing better result for surface treated nanoparticles. The plane-stress fracture toughness, evaluated by the essential work of fracture approach, manifested a dramatic increase (up to 64%) with the BA content, with no significant differences among the various types of BA nanoparticles.

In this study asymmetrically reinforced epoxy (EP)/carbon fibre (CF) fabric composites were prepared and their shape memory properties were quantified in both unconstrained and fully constrained flexural tests performed in a dynamic mechanical analyser (DMA). Asymmetric layering was achieved by incorporating two and four CF fabric layers whereby setting a resin- and reinforcement-rich layer ratio of 1/4 and 1/2, respectively. The recovery stress was markedly increased with increasing CF content. The related stress was always higher when the CF-rich layer experienced tension load locally. Specimens with CF-rich layers on the tension side yielded better shape fixity ratio, than those with reinforcement layering on the compression side. Cyclic unconstrained shape memory tests were also run up to five cycles on specimens having the CF-rich layer under local tension. This resulted in marginal changes in the shape fixity and recovery ratios.

The morphology of peroxide-cured, styrene crosslinked, bisphenol A-based vinyl ester (VE) resin was investigated by atomic force microscopy (AFM) after ‘physical’ etching with different methods. Etching was achieved by laser ablation, atmospheric plasma treatment and argon ion bombardment. Parameters of the etching were varied to get AFM scans of high topography resolution. VE exhibited a nanoscaled nodular structure the formation of which was ascribed to complex intra- and intermolecular reactions during crosslinking. The microstructure resolved after all the above physical etching techniques was similar provided that optimized etching and suitable AFM scanning conditions were selected. Nevertheless, with respect to the ‘morphology visualization’ these methods follow the power ranking: argon bombardment > plasma treatment > laser ablation.

The fracture resistance of different rubbers containing various nanofillers, such as multiwall carbon nanotube (MWCNT), organoclay, silica and carbon black (CB), was determined by the J-integral making use of the single edge notched tensile loaded (SEN-T) single specimen approach. The elastomeric matrices were natural (NR), ethylene propylene diene (EPDM) and hydrogenated nitrile rubbers (HNBR). Moreover, the strain softening (Payne effect) of selected rubbers with 30 part per hundred rubber (phr) filler content was also investigated by dynamic mechanical thermal analysis (DMTA) in shear mode. DMTA results indicated that the Payne effect follows the ranking: MWCNT(fibrous) > organoclay(platy) > silica(spherical). J-resistance (JR) curves were constructed by plotting the J value as a function of the crack tip opening displacement (CTOD*), monitored during loading. CTOD* = 0.1 mm was considered as crack initiation threshold and thus assigned to the critical value JIc. JIc increased with increasing filler loading, whereby MWCNT outperformed both silica and CB. On the other hand, JIc did not change with filler loading for the NR/organoclay systems that was traced to straininduced crystallization effect in NR. The tearing modulus (TJ) also increased with increasing filler loading. The related increase strongly depended on both rubber and filler types. Nonetheless, the most prominent improvement in TJ among the fillers studied was noticed for the fibrous MWCNT.

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