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Evanescent field excitation is a powerful means to achieve a high surface-to-bulk signal ratio for bioimaging and sensing applications. However, standard evanescent wave techniques such as TIRF and SNOM require complex microscopy setups. Additionally, the precise positioning of the source relative to the analytes of interest is required, as the evanescent wave is critically distance-dependent. In this work, we present a detailed investigation of evanescent field excitation of near-surface waveguides written using femtosecond laser in glass. We studied the waveguide-to-surface distance and refractive index change to attain a high coupling efficiency between evanescent waves and organic fluorophores. First, our study demonstrated a reduction in sensing efficiency for waveguides written at their minimum distance to the surface without ablation as the refractive index contrast of the waveguide increased. While this result was anticipated, it had not been previously demonstrated in the literature. Moreover, we found that fluorescence excitation by waveguides can be enhanced using plasmonic silver nanoparticles. The nanoparticles were also organized in linear assemblies, perpendicular to the waveguide, with a wrinkled PDMS stamp technique, which resulted in an excitation enhancement of over 20 times compared to the setup without nanoparticles. [ABSTRACT FROM AUTHOR]

Metal@silica concentric nanoparticles capable of metal-enhanced fluorescence (MEF) represent a powerful means to improve the brightness and stability of encapsulated organic fluorophores and are finding numerous applications in biology, analytical chemistry, and medical diagnostics. The rational design of MEF-enabled labels and sensors often involves comparing fluorescence enhancement factors (EF) between nanostructures having different structural properties (e.g., metal core diameter, silica shell thickness, extent of spectral overlap between plasmon band and fluorophore). Accurate determination of EFs requires the measurement of fluorescence emission intensity in the presence and absence of the plasmonic core while minimizing the impact of physical and chemical artifacts (e.g., signal variations due to scattering, adsorption, sedimentation). In this work, Ag@SiO@SiO + x (where x is fluorescein, eosin, or rhodamine B) nanostructures were synthesized with excellent control of core size, silica spacer shell thickness and fluorophore concentration. Using UV-VIS spectrometry, spectrofluorimetry, time-resolved fluorometry, and transmission electron microscopy, we investigated the influence of these key structural factors on fluorescence emission intensity, and the results were used to develop a generalized methodology for the determination of fluorescence enhancement factors in Ag@SiO core-shell nanoparticles. This methodology should be of general importance to designing MEF-enabled nanostructures, sensors, and related analytical techniques. [ABSTRACT FROM AUTHOR]

Context: During the COVID-19 pandemic, restrictions were imposed on visits in hospitals in the province of Quebec, Canada in an effort to reduce the risk of viral exposure by minimizing face-to-face contact in order to protect patients, visitors and staff. These measures led to social isolation for patients. In order to reduce this isolation, CHUM (the Centre hospitalier de l'Université de Montréal, a teaching hospital) shifted from in-person visits to courtesy telephone calls delivered by volunteers from CHUM's Volunteers, Recreation and Leisure Department. Objectives: To study: (1) the contribution made by these calls to reducing isolation and their limitations, (2) how the calls can be improved, and (3) whether they should be maintained, based on the views of patients and volunteers. Methodology: This study examined two populations. The first one consisted of 189 adult patients hospitalized at CHUM who received a courtesy phone call from a volunteer and the second one consisted of the 25 CHUM volunteers who made these calls. Quantitative data were collected from patients and volunteers through questionnaires and a Smartsheet. The patient questionnaire evaluated isolation, the courtesy phone calls, the relationship of trust with the volunteer and sociodemographic questions. The volunteer questionnaire evaluated the appropriateness of the technology for the intervention, the support and training received, the impacts of the courtesy phone call on both the patients and the volunteers, an experience report and sociodemographic information. In addition, a focus group was held with 7 volunteers. Then the verbatim were transcribed and analyzed using QDA miner software. Results: From April 27, 2020 to September 5, 2020 more than 11,800 calls were made, mainly concerning hospitalization conditions or home follow-ups (n = 83), and relationships with relatives, friends, and family (n = 79). For 73.6% of hospitalized patients, the courtesy calls from volunteers were a good response to their needs, and 72% of volunteers agreed. 64.5% of patients felt less isolated and 40% of volunteers felt useful. Conclusion: Our data suggest that patients felt less isolated during their hospitalization because of the courtesy calls made by the volunteers, that smartphones could also be used for video calls and, finally, that maintaining this type of service seems as relevant after as during a pandemic to provide social interactions to people isolated for medical reasons. [ABSTRACT FROM AUTHOR]

Context: The National Institute of Excellence in Health and Social Services (INESSS), which functions as the Québec health technology assessment (HTA) agency, tested a new way to engage patients along with health‐care professionals in the co‐construction of recommendations regarding implantable cardioverter‐defibrillator replacement. Objective: The objective of this article was to describe the process of co‐construction of recommendations and to propose methods of building best practices for patient involvement (PI) in HTA. Design: Throughout the process, documents were collected and participant observations were made. Individual interviews were conducted with patients, health‐care professionals and the INESSS scientific team, from January to March 2018. Results: Three committees were established: an expert patient committee to reflect on patient experience literature; an expert health professional committee to reflect on medical literature; and a co‐construction committee through which both patients and health‐care professionals contributed to develop the recommendations. The expert patients validated and contextualized a literature review produced by the scientific team. This allowed the scientists to consider aspects related to the patient experience and to integrate the feedback from patients into HTA recommendations. The most important factor contributing to a positive PI experience was the structured methodology for selecting patient participants, and a key factor that inhibited the process was a lack of training in PI on the part of the scientific team. Conclusions: This experience demonstrates that it is possible to co‐construct recommendations, even for technically complex HTA subjects, through a more democratic process than usual which led to more patient‐focused guidance. [ABSTRACT FROM AUTHOR]