Application of mesoporous silica nanoparticles (MSNs) as antifouling/antibacterial carriers is limited and specifically with a dual synergetic effect. In the present work, MSNs modified with quaternary ammonium salts (QASs) and loaded with the biocide Parmetol S15 were synthesized as functional fillers for antifouling/antibacterial coatings. From the family of the MSNs, MCM-48 was selected as a carrier because of its cubic pore structure, high surface area, and high specific pore volume. The QASs used for the surface modification of MCM-48 were dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride and dimethyltetradecyl[3-(triethoxysilyl)propyl]ammonium chloride. The QAS-modified MCM-48 reveals strong covalent bonds between the QAS and the surface of the nanoparticles. The surface functionalization was confirmed by Fourier transform infrared spectroscopy, thermogravimetric analysis, elemental analysis, and ζ-potential measurements. Additional loading of the QAS-modified MCM-48 with a commercially available biocide (Parmetol S15) resulted in a synergetic dual antibacterial/antifouling effect. Either loaded or unloaded QAS-modified MSNs exhibited high antibacterial performance confirming their dual activity. The QAS-modified MCM-48 loaded with the biocide Parmetol S15 killed all exposed bacteria after 3 h of incubation and presented 100% reduction at the antibacterial tests against Gram-negative and Gram-positive bacteria. Furthermore, the QAS-modified MCM-48 without Parmetol S15 presented 77-89% reduction against the exposed Gram-negative bacteria and 78-94% reduction against the exposed Gram-positive bacteria. In addition, the modified MCM-48 was mixed with coating formulations, and its antifouling performance was assessed in a field test trial in northern Red Sea. All synthesized paints presented significant antifouling properties after 5 months of exposure in real seawater conditions, and the dual antifouling effect of the nanoparticles was confirmed.

Background The delivery of orthopaedic care via telemedicine services has the potential to promote accessibility and decrease medical care expenses, while facilitating the control of infectious disease spreading. The purpose of this study was to assess agreement regarding diagnosis, recommended course of management and the perceived need for additional diagnostic testing between a video examination (VE) and a face to face (FTF) assessment of patients with shoulder disorders. Methods Forty-seven (18 females) patients presenting to a shoulder surgery clinic were assessed consecutively by VE and a FTF examination. All assessments were conducted by a shoulder specialist. Agreement regarding the established diagnosis, the recommended course of management and the need for additional diagnostic tests was assessed using percent agreement and kappa (95% CI) coefficient. Differences in the content, duration and satisfaction between the two examination modes were also assessed. Results Percent agreement and kappa (95% CI) coefficient for agreement regarding diagnosis were 85.1% and 0.82 (0.69-0.94), respectively. Percent agreement and kappa (95% CI) coefficient regarding the recommended course of management and the need for additional diagnostic testing were 61.7% and 0.43 (0.22-0.63), and 74.5% and 0.49 (0.25-0.74), respectively. The VE resulted in collection of less physical examination information, took longer to complete and was associated with less satisfaction by both patient and examiner. Conclusions Video examination of patients with shoulder disorders may present a valid alternative to FTF examination. Nevertheless, the content of the video-based physical examination may need to be modified to facilitate a clearer detection of indications for specific interventions or diagnostic tests.

One of the current challenges in maritime antifouling is the development of new nanostructured coatings which can replace the old protection coatings based on tributyltin biocides prohibited by EU and US legislation as ecologically dangerous. In our study, antibacterial/ antifouling polymer coatings containing innovative dual functionalized nanocapsules demonstrate high antifouling activity in various tests. Capsules are MCM-48 SiO 2 nanoparticles loaded with eco-friendly 4,5dichloro-2-octyl-4-isothiazolin-3-one (DCOIT) antifouling agent and decorated with dimethyloctadecyl [3-(trimethoxysilyl) propyl] ammonium chloride or dimethyltetradecyl [3-(triethoxysilyl) propyl] ammonium chloride (quaternary ammonium salts, QASs) also possessing antifouling activity. Cross section images of the coatings demonstrated the absence of the capsule aggregates in the coatings with slight increase of the surface roughness. The formulated coatings revealed excellent antibacterial performance against E. coli and Staphylococcus aureus according to ISO 22196:2011 protocol. This antifouling activity was also confirmed by immersion of the coated polyvinyl chloride (PVC) panels at a depth of 8−9 m in the sea (Eilat, Israel). Biofouling coverage of 6.9% was observed for nanocapsulesloaded coatings (5 wt % concentration of nanocapsules) compared to the 49% of the coverage for nonmodified coating after 6 months of immersion. The nanocapsules-loaded coatings with dual antifouling functionality demonstrated antifouling activity even after complete release of encapsulated DCOIT because of chemically attached QAS groups on the nanoparticles surface. Moreover, active antifouling materials presented in nanocapsules do not demonstrate any toxicity to the brine shrimps Artemia salina, which are widely used in the food industry.

There is an increasing interest in developing innovative coatings and testing natural products with anti-fouling activity to substitute current highly toxic biocides that have a harmful impact on marine organisms. Bacillus licheniformis species have shown different anti-biofilm and anti-fouling activities in vitro, but so far, its efficacy in field trials has not been tested. For this purpose, the capacity of different extracts of B. licheniformis NCTC 10341T to prevent micro and macro-fouling was first tested in vitro. The methanol cell extract (MCE) inhibited bacterial biofilm formation without significantly affecting planktonic growth and displayed a significant efficacy to prevent larval settlement of the macro-fouler Bugula neritina in vitro without inducing lethality. Additionally, the MCE presented low toxicity against the non-target species Artemia salina. The B. licheniformis MCE was then incorporated in a self-polishing paint at 2 and 5% w/w and tested in a static immersion experiment in the Gulf of Aqaba (northern Red Sea) for 180 days. Fouling coverage decreased by 30% in the 5% MCE-treated panels in comparison with the control panels. Differences in the anti-biofilm activity of the extracts depending on the culture medium highlight the importance of the strict control of culture conditions for the production of biomass with stable bioactive activity. The results indicate the potential of B. licheniformis NCTC 10341T crude extracts for environmentally friendly anti-fouling applications, although a deeper characterization of the bioactive compounds present in the B. licheniformis MCE and its mode of action is required to allow strict control of the activity of the extracts to achieve large-scale industrial production.