Intrinsic strong light-matter coupling with self-hybridized bound states in the continuum in van der Waals metasurfaces.

Photonic bound states in the continuum (BICs) provide a standout platform for strong light-matter coupling with transition metal dichalcogenides (TMDCs) but have so far mostly been implemented as traditional all-dielectric metasurfaces with adjacent TMDC layers, incurring limitations related to strain, mode overlap and material integration. Here, we demonstrate intrinsic strong coupling in BIC-driven metasurfaces composed of nanostructured bulk tungsten disulfide (WS2) and exhibiting resonances with sharp, tailored linewidths and selective enhancement of light-matter interactions. Tuning of the BIC resonances across the exciton resonance in bulk WS2 is achieved by varying the metasurface unit cells, enabling strong coupling with an anticrossing pattern and a Rabi splitting of 116 meV. Crucially, the coupling strength itself can be controlled and is shown to be independent of material-intrinsic losses. Our self-hybridized metasurface platform can readily incorporate other TMDCs or excitonic materials to deliver fundamental insights and practical device concepts for polaritonic applications

Prevalence and Antibiotic Resistance Phenotypes of Pseudomonas spp. in Fresh Fish Fillets

In fresh fish products, excessive loads of Pseudomonas can lead to their rapid spoilage. It iswise for Food Business Operators (FBOs) to consider its presence both in whole and prepared fishproducts. With the current study, we aimed to quantify Pseudomonas spp. in fresh fillets of Salmosalar, Gadus morhua and Pleuronectes platessa. For all three fish species, we detected loads ofpresumptive Pseudomonas no lower than 104 –105 cfu/g in more than 50% of the samples. We isolated55 strains of presumptive Pseudomonas and carried out their biochemical identification; 67.27% ofthe isolates were actually Pseudomonas. These data confirm that fresh fish fillets are normallycontaminated with Pseudomonas spp. and the FBOs should add it as a “process hygiene criterion”according to EC Regulation n.2073/2005 n.2073/2005. Fu rthermore, in food hygiene, it is worthevaluating the prevalence of antimicrobial resistance. A total of 37 Pseudomonas strains were testedagainst 15 antimicrobials, and they all were identified as being resistant to at least one antimicrobial,mainly penicillin G, ampicillin, amoxicillin, tetracycline, erythromycin, vancomycin, clindamycinand trimethoprim. As many as 76.47% of Pseudomonas fluorescens isolates were multi-drug resistant.Our results confirm that Pseudomonas is becoming increasingly resistant to antimicrobials and thusshould be continuously monitored in foods