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Marine mussels strongly adhere to various surfaces under a variety of conditions. In order to understand the basic mechanism involved, we study the adsorption of L-dopa molecule on (001) surface of hydrophilic geminal and terminal silica. High content of modified amino acid L-dopa is found in the glue-like material secreted by the Mussels through which it sticks to various surfaces underwater. To understand the adsorption behavior, we have made use of periodic Density Functional Theory (DFT) study. The L-dopa molecule adheres to silica surfaces terminated with geminal and terminal silanols via its catechol part. In both the cases, the adhesion is achieved through the formation of 4 H-bonds. A binding energy of 29.48 and 31.67 kcal/mol has been estimated, after the inclusion of dispersion energy, for geminal and terminal silica, respectively. These results suggest a relatively stronger adhesion of dopa molecule with terminal silica.

Ho-doped La 2 O 3 phosphor particles were synthesized by simple and environmental friendly Urea Homogeneous Precipitation (UHP) technique. Structural and optical properties of the prepared particles were investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and photoluminescence (PL) spectroscopy. XRD characterizations showed the formation of pure hexagonal La 2 O 3 phase and its recrystallization into La(OH) 3 phase in open atmosphere. The luminescence behavior in both the structures was investigated and compared at three different Ho 3+ doping concentration. Under 232 nm excitation source, the intense emission for both structures was observed at 548 nm. The intensity of emission peaks and corresponding luminescence in La(OH) 3 was observed to be lower as compared to the luminescence from La 2 O 3 structure.

In present study, La 2 O 3 :Ce 3+ phosphor particles were successfully synthesized via urea homogeneous precipitation (UHP) technique. X-ray diffraction, field-emission scanning electron microscopy, FTIR and photoluminescence spectroscopy were used to analyze the structure and optical properties of the fabricated particles. Under 310 nm excitation, the samples showed emission at 365 nm and 372 nm corresponding to transitions 5 d 1 → 2 F 5/2 and 5 d 1 → 2 F 7/2 , respectively. The dependence of the luminescence emission on various Ce 3+ doping concentration was investigated and optimal doping concentration was determined to be 2 mol%. The luminescence emission of La 2 O 3 : Ce 3+ in UV region might find applications in light industry.

Using periodic Density Functional Theory (DFT) calculations and DFT-based molecular dynamics simulations, we studied the adhesion mechanism of glycine amino acid and the catechol part of L-dopa on the cristobalite surface. The optimized glycine and catechol molecules are initially placed vertically 3 A above the cristobalite surface with a vacuum thickness of approximately 40 A. The catechol adhesion on the cristobalite surface previously studied showed strong binding energy both in dry and wet adsorption. Glycine is the second most abundant amino acid in the mussel adhesive protein, which would have a significant contribution in mussel adhesion. This study of glycine will further enlighten the understanding of marine mussel adhesion. We believe that all the proteins exist in the Mytilus edulis foot protein (mefp) are contributing in this unique and versatile adhesion of marine mussel. We observed that glycine molecules formed four hydrogen bonds with the surface silanols and acted as donors and acceptors. Four hydrogen bond formation is also observed during catechol adhesion on the cristobalite surface. The average binding energy of both molecules on the cristobalite surface lies in the range of hydrogen binding energy. Surface binding energy values of 20.23 and 14.45 kcal mol−1 were obtained for glycine and catechol adsorption, respectively. Including the dispersion energy term further raised the binding energy to 31.29 kcal mol−1 for glycine and 28.58 kcal mol−1 for catechol. The binding energy values suggest that glycine adsorption on the dry cristobalite surface is much stronger as compared to that of catechol.

Background. The relative rarity and diversity of fibrotic interstitial lung disease (ILD) have made it challenging to study these diseases in single-centre cohorts. Here we describe formation of a multicentre Canadian registry that is needed to describe the outcomes of fibrotic ILD and to enable detailed healthcare utilization analyses that will be the cornerstone for future healthcare planning.Methods. The Canadian Registry for Pulmonary Fibrosis (CARE-PF) is a prospective cohort anticipated to consist of at least 2,800 patients with fibrotic ILD. CARE-PF will be used to (1) describe the natural history of fibrotic ILD, specifically determining the incidence and outcomes of acute exacerbations of ILD subtypes and (2) determine the impact of ILD and acute exacerbations of ILD on health services use and healthcare costs in the Canadian population. Consecutive patients with fibrotic ILD will be recruited from five Canadian ILD centres over a period of five years. Patients will be followed up as clinically indicated and will complete standardized questionnaires at each clinic visit. Prespecified outcomes and health services use will be measured based on self-report and linkage to provincial health administrative databases.Conclusion. CARE-PF will be among the largest prospective multicentre ILD registries in the world, providing detailed data on the natural history of fibrotic ILD and the healthcare resources used by these patients. As the largest and most comprehensive cohort of Canadian ILD patients, CARE-PF establishes a network for future clinical research and early phase clinical trials and provides a platform for translational and basic science research.

Fine scintillator strips with 1 cm widths and 3 mm thicknesses have been produced with an extrusion technique. Each strip has a 1-mm hole along the strip for a wavelength-shifter ber. The technique has several advantages in comparison with the casting method. The strip's light yield shows a su cient number of photoelectrons, indicating that its quality is comparable to that of a strip produced with the casting method. The strip was exposed to a harsh radiation environment. We discuss the results of irradiation and the e ects of annealing.

Legionella pneumophila is the primary etiologic agent of legionellosis, a potentially fatal respiratory illness. Amongst the sixteen described L. pneumophila serogroups, a majority of the clinical infections diagnosed using standard methods are serogroup 1 (Sg1). This high clinical prevalence of Sg1 is hypothesized to be linked to environmental specific advantages and/or to increased virulence of strains belonging to Sg1. The genetic determinants for this prevalence remain unknown primarily due to the limited genomic information available for non-Sg1 clinical strains. Through a systematic attempt to culture Legionella from patient respiratory samples, we have previously reported that 34% of all culture confirmed legionellosis cases in Ontario (n = 351) are caused by non-Sg1 Legionella. Phylogenetic analysis combining multiple-locus variable number tandem repeat analysis and sequence based typing profiles of all non-Sg1 identified that L. pneumophila clinical strains (n = 73) belonging to the two most prevalent molecular types were Sg6. We conducted whole genome sequencing of two strains representative of these sequence types and one distant neighbour. Comparative genomics of the three L. pneumophila Sg6 genomes reported here with published L. pneumophila serogroup 1 genomes identified genetic differences in the O-antigen biosynthetic cluster. Comparative optical mapping analysis between Sg6 and Sg1 further corroborated this finding. We confirmed an altered O-antigen profile of Sg6, and tested its possible effects on growth and replication in in vitro biological models and experimental murine infections. Our data indicates that while clinical Sg1 might not be better suited than Sg6 in colonizing environmental niches, increased bloodstream dissemination through resistance to the alternative pathway of complement mediated killing in the human host may explain its higher prevalence.