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Context. Filamentary structures are ubiquitous in the interstellar medium. Investigating their connection to the large-scale structure of the Galaxy and their role in star formation is leading to a paradigm shift in our understanding of star formation. Aims. We study the properties of filamentary structures from the ATLASGAL survey, which is the largest and most sensitive systematic ground-based survey of the inner Galactic plane at submillimeter wavelengths. Methods. We use the DisPerSE algorithm to identify spatially coherent structures located across the inner-Galaxy (300• < < 60• and |b| < 1.5). As a result we produce a catalogue of ∼1800 structures; these were then independently classified by the five lead authors into one of the following types: marginally resolved, elongated structures, filaments, network of filaments and complexes. This resulted in the identification of 517 filamentary structures. We determine their physical properties and investigate their overall Galactic distribution.Results. We find that almost 70% of the total 870 µm flux associated with these structures resides in filaments and networks of filaments and we estimate that they are likely to be associated with a similar fraction of the mass. Correlating these structures with tracers of massive star formation we also find that a similar fraction of the massive star forming clumps are associated with filaments and networks of filaments, which highlights the importance of these types of structures to star formation in the Galaxy. We have determined distances, masses and physical sizes for 241 of the filamentary structures. We find a median distance of 3.8 kpc, a mean mass of a few 10 3 M , a mean length of ∼6 pc and a mass-to-length ratio of (M/L) ∼200-2000 M pc −1 . We also find that these filamentary structures are tightly correlated with the spiral arms in longitude and velocity, and that their semi-major axis is preferentially aligned parallel to the Galactic mid-plane and therefore with the direction of large-scale Galactic magnetic field. We find many examples where the dense filaments identified in ATLASGAL are associated with larger scale filamentary structures (∼100 pc), and argue that this is likely to be common, and as such these may indicate a connection between large-scale Galactic dynamics and star formation. Conclusions. We have produced a large and Galaxy-wide catalogue of dense filamentary structures that are representative of a particular size and mass range not previously well studied in the literature. Analyses of the properties and distribution of these filaments reveals that they are correlated with the spiral arms and make a significant contribution to star formation in the Galaxy. Massive star formation is ongoing within ∼20% of the filaments and is strongly correlated with the filaments with the largest mass-tolength ratios. The luminosity of the embedded sources has a similar distribution to the Galactic-wide samples of young massive stars and can therefore be considered to be representative.

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Topics related to ionic liquid (IL)-based catalysis with solids not only open new ways for studies of heterogeneous catalysts, but also minimize many of the negative effects that current ILs have encountered. This review evaluates the various examples in solid-based heterogeneous catalytic systems that have been developed with the aid of ILs. Catalysis over ready-made solid catalysts in the presence of ILs, immobilizations of homogeneous organic and organometallic catalysts with the concepts of supported ionic liquid phase catalysis, metal nanoparticles catalysts in ILs, catalysis over supported ILs as well as metal complexes and the preparation of solid catalysts by using ILs as solvents have been described. In several cases, detailed information on the performance concerning catalytic activity and recyclability is available.

Porcine epidemic diarrhea virus (PEDV) is a coronavirus that induces persistent diarrhoea in swine, resulting in severe economic losses in swine-producing countries. Insights into the interplay between PEDV infection and the innate immune system are necessary for understanding the associated mechanism of pathogenesis. The transcription factor NF-kB plays an important role in regulating host immune responses. Here, we elucidated for the first time to our knowledge the potential mechanism of PEDV-mediated NF-kB activation in porcine small intestinal epithelial cells (IECs). During PEDV infection, NF-kB p65 was found to translocate from the cytoplasm to the nucleus, and PEDV-dependent NF-kB activity was associated with viral dose and active replication. Using small interfering RNAs to screen different mRNA components of the Toll-like receptor (TLR) or RIG-I-like receptor signalling pathways, we demonstrated that TLR2, TLR3 and TLR9 contribute to NF-kB activation in response to PEDV infection, but not RIG-I. By screening PEDV structural proteins for their ability to induce NF-kB activities, we found that PEDV nucleocapsid protein (N) could activate NF-kB and that the central region of N was essential for NF-kB activation. Furthermore, TLR2 was involved in PEDV N-induced NF-kB activation in IECs. Collectively, these findings provide new avenues of investigation into the molecular mechanisms of NF-kB activation induced by PEDV infection.