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ICRS are polymethylmethacrylate (PMMA) implants developed to be inserted in the corneal stroma aiming to remodel the ectatic corneal curvature. In 2000, ICRS have been introduced for the implantation in KC treatment. Since then, several authors have demonstrated the efficacy of this surgical procedure for improving the refractive and topographic results of KC patients. Moreover, the method has been extended to a larger spectrum of corneal ectasia, such as pellucid marginal degeneration (PMD) and iatrogenic ectasia after laser in situ keratomileusis (LASIK). Our aim was to evaluate the functional results, i.e. how uncorrected and corrected distance visual acuity can be improved by implantation of ICRS. Progression of ectasia seems to be retarded. However, consistent follow‐up visits at close intervals are necessary to identify complications at an early stage. The complications after ICRS implantation are rare due to strict patient selection and modern surgical techniques. [ABSTRACT FROM AUTHOR]

An aboveground pilot-scale biofilter filled with wood chips was tested to treat ammonia emissions from a piggery located in Brittany (France). Two long-term tests (“summer” and “autumn” experiments) were carried out to improve biofilter applications for agriculture. The influence of climatic conditions on biofilter performance was taken into account. During summer 2012, the biofilter was operated for 74 days at different empty bed residence times (EBRTs) from 6 to 15 s. Inlet NH3 concentrations were relatively constant (around 15 mg m−3). Significant NH3 reductions were achieved at EBRT = 12 s (removal efficiencies, RE, ranged between 90 and 100% for loading rates, LR, of around 4 g m−3 h−1). At a lower EBRT (6 s), RE dropped to roughly 30–50%. This was due to the dramatic increase in the loading rate (LR up to 12 g m−3 h−1) but the results showed that the change in atmospheric conditions (temperature and relative humidity) also had a significant influence on biofilter performance. It was evidenced that the use of a humidifier upstream of the biofilter must be taken into account for large-scale biofilter design, but only for specific conditions (the spraying of the biofilter having to be carried out exceptionally). During autumn 2012, the biofilter was operated for 116 days at EBRT = 12 s. RE were around 80% for LR of around 3 g m−3 h−1. In such autumnal atmospheric conditions, a demister system should be installed upstream of the biofilter in order to avoid water accumulation in the bed material. Although biofiltration was suitable for NH3 treatment of piggery air, the need to control accurately the medium moisture content implies that biofilters would not be easily managed by a pig farmer. [Copyright &y& Elsevier]

The absolute adsorption isotherms are necessary to correctly evaluate the selectivity of the adsorbent material or to design adsorption processes at high pressure (e.g., H purification from syngas processes, removal of acid gas from natural gas,...). The aim of this work is thus to propose an easy method to correct the buoyancy effect of the bulk phase on the adsorbed phase volume during both pure gas and gas mixtures adsorption for pressures up to 10 MPa. The potential theory of adsorption and the Dubinin-Radushkevich relation are adapted by introducing mixing parameters based on simple Berthelot rules. The concept of internal pressure used to characterize the adsorbed phase is also adapted for mixtures. The method is then improved on a commercial activated carbon (AC), when adsorbing pure HS and CH, and their mixtures up to 5 MPa. The study points out the importance to carefully consider the buoyancy effect of the bulk phase on the adsorbed phase volume. Its impact on the adsorbent material selectivity at high pressures could affect the design and the performances of PSA or TSA processes. For example, only considering the excess adsorption data leads to an apparent selectivity 13 % greater than the absolute one for a concentration of 6 ppm of HS in a CH matrix at 5 MPa (298 K) on the AC. [ABSTRACT FROM AUTHOR]

Poly(methyl methacrylate) (PMMA) thin films of various tacticity and thickness were bombarded at grazing angles by 20 MeV Au ions at different temperatures. The shape of the tracks was investigated by scanning force microscopy (SFM) after annealing for various time at different temperatures and constant quenching rate. The thickness dependent glass transition temperature, Tg(h), was estimated from the temperature of relaxation of ion-caused nanodeformations in the films. Tg(h) obtained from the thermal healing of the holes and hillocks is found in good agreement with the one determined by variable temperature ellipsometry for PMMA film thickness of 80 nm and corresponds to the Tg of each bulk PMMA stereoisomer. Below this thickness, some significant divergences are observed between the Tg measured by the two techniques. We propose that the healing of ion crater hillock and the kink in the thermal expansion arise from the different nature of chains motions which are perturbed to different extents according to the main polymer chain preferential orientation in the thin film. This can be tentatively interpreted by a so-called “anisotropic” character of the glass transition. [ABSTRACT FROM AUTHOR]

SAM68 is an mRNA-binding protein involved in mRNA processing in the nucleus that forms membraneless compartments called SAM68 Nuclear Bodies (SNBs). We found that intersectin 1 (ITSN1), a multidomain scaffold protein harboring five soluble SH3 domains, interacts with SAM68 proline-rich motifs (PRMs) surrounded by self-adhesive low complexity domains. While SAM68 is poorly soluble in vitro, the interaction of ITSN1 SH3 domains and mRNA with SAM68 enhances its solubility. In HeLa cells, the interaction between the first ITSN1 SH3 domain (SH3A) and P0, the N-terminal PRM of SAM68, induces the dissociation of SNBs. In addition, we reveal the ability of another SH3 domain (SH3D) of ITSN1 to bind to mRNAs. ITSN1 and mRNA may thus act in concert to promote SAM68 solubilization, consistent with the absence of mRNA in SNBs in cells. Together, these results support the notion of a specific chaperoning of PRM-rich SAM68 within nuclear ribonucleoprotein complexes by ITSN1 that may regulate the processing of a fraction of nuclear mRNAs, notably SAM68-controlled splicing events related to higher neuronal functions or cancer progression. This observation may also serve as a putative model of the interaction between other PRM-rich RBPs and signaling proteins harboring SH3 domains. [ABSTRACT FROM AUTHOR]

In the present manuscript, a numerical sensitivity analysis is conducted on different physical parameters in order to assess the robustness of a 3D CFD simulation of adsorption process cycles. It is demonstrated that the effective thermal conductivity of the porous medium, the mass transfer coefficient, the column dead volumes, the equilibrium isotherm model choice, are all crucial parameters to model accurately adsorption kinematics and heat transfer through a packed porous bed using 3D CFD approach. Moreover, it is found that the initial condition imposed on the adsorbed phase at the start of a steady PSA cycle, is a crucial point to predict accurately the mass transfer and the displacement of the adsorption front in 3D CFD computations. [ABSTRACT FROM AUTHOR]

Background. Evolutionary conserved scaffold protein ITSN1 involved in clathrin-mediated endocytosis and signaling was recently shown to undergo nuclear-cytoplasmic shuttling. Although ITSN1 was found to interact with RNA-binding protein SAM68, the functional role of the interaction is unknown. Aim. The aim of the work was to analyze the structural basis of the ITSN1-SSAM68 interaction and to examine the effect of ITSN1 on SAM68 functioning. Methods. For GST pull-down assay, ITSN1 SH3 domains fused to GST were used to precipitate endogenous SAM68 or GFP-fused truncated forms of SAM68 from HEK lysates. Western blot analysis with anti-SAM68 and anti-GFP antibodies was used to detect the proteins. For sedimentation assay, purified recombinant proteins GST-ITSN1SH3 and SAM68-His were incubated in binding buffer and centrifuged at low speed. The protein content in pellet and supernatant fractions was estimated by SDS-PAGE and Coomassie staining. For immuno-fluorescent microscopy, HeLa cells transiently transfected with GFP-ITSN1 were fixed and stained with anti-SAM68 and Alexa Fluor 594-conjugated antibodies. For ITSN1 knockdown, HeLa cells were infected with lentiviral particles encoding ITSN1-specific shRNA. The expression of SAM68-regulated transcripts was evaluated using quantitative real-time PCR. Results. Based on the results of GST pull-down assay, it was found that SAM68 interacted with ubiquitously expressed and neuron-specific isoforms of ITSN1 SH3A domain. The class II proline motif (PxxPxR) that interacts with the SH3A domain of ITSN1 is present in the N-terminal low complexity region of SAM68. Using expression constructs encoding truncated forms of SAM68, it was found that ITSN1 SH3 domains precipitated N-terminal fragment of SAM68 confirming that ITSN1 interacts with PPLPHR motif (38-44 aa) of SAM68. Next, it was shown that ITSN1 SH3 domains facilitated solubilization of SAM68 aggregates in vitro whereas the accumulation of overexpressed ITSN1 in HeLa cells nuclei abolish the formation of SAM68 nuclear bodies specific for some transformed cell lines. Finally, it was found that ITSN1 knockdown altered SAM68-mediated splicing events in HeLa cells, particularly significantly increasing the expression of the pro-oncogenic isoform of splicing factor ASF/SF2. Conclusions. The current work demonstrated that ITSN1-SAM68 interaction is mediated by the SH3A domain of ITSN1 and the N-terminal low-complexity region of SAM68. ITSN1 induces the dissociation of SAM68 aggregates in vitro and in vivo whereas ITSN1 knockdown in HeLa cells affects splicing events controlled by SAM68 suggesting the presence of a novel nucleus-cytoplasm signaling crosstalk. [ABSTRACT FROM AUTHOR]

The formation of insoluble TDP-43 and FUS cytoplasmic inclusions are critical for the onset and progression of devastating neurodegenerative disorders like amyotrophic lateral sclerosis (ALS) or frontotemporal lobar degeneration (FTLD). These proteins are predominantly nuclear but, as many other proteins involved in mRNA metabolism and transport, they actively shuttle in and out of the nucleus under physiological conditions. However, in affected neurons, they are found enriched in the cytoplasm and form cytoplasmic inclusion. If the mechanisms driving the onset of ALS and FTLD remain unknown, one can assume that the loss of normal TDP-43 and FUS functions is probably involved in neuron degeneration. First, these proteins bind to a huge number of mRNAs and, by doing so, regulate the translation efficiency. Second, TDP-43 and FUS are components of RNA transport granules which have important functions in neurons. For example, ALS linked mutations of TDP-43 impair the transport of RNA granules to distal neuronal compartments. Finally, due to their RNA recognition motif and their prion-like domain, both proteins are recruited in cytoplasmic stress granules upon stress conditions in a reversible manner. However, in pathological conditions, stress granule dynamics is deregulated, with the appearance of RNA granules of different morphologies and which, in contrast with stress granules, can no longer be dissociated after stress. The role of TDP-43 and FUS in devastating neurodegenerative disorders explains the numerous studies on this subject both at the animal and cellular level but strikingly, structural analysis of the protein-RNA complexes has received little attention except for the potential amyloid characteristic of the filaments observed in inclusions of ALS or FTLD patients. To that end, we propose here a structural analysis at the single molecule level using Atomic Force Microscopy (AFM) of TDP-43-RNA and FUS-RNA complexes. We will take advantage of the high resolution imaging possibilities of AFM to detect potential differences in the binding mode of these proteins to RNA and the influence of RNA-binding proteins present in RNA granules on the stability of the TDP-43- and FUS-RNA complexes. [ABSTRACT FROM AUTHOR]