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Natural photosynthetic biofilms were incubated under light (100 mmol m?2 s?1) and dark conditions to elucidate the impact of photosynthesis on bacterial production, abundance, biovolume, biomass, and enzyme activities over 24 h. Use of organic carbon-free media limited carbon sources to algal photosynthesis and possibly the polysaccharides of the biofilm matrix. Bacterial production of biofilm communities was significantly higher in light incubations (p < 0.001). The greatest differences in production rates between light and dark incubations occurred between 8 and 24 h. Biomass-specific a- and b-glucosidase and b-xylosidase activities were stimulated by photosynthesis, with significantly greater activities occurring at hours 16 and 24 in the light treatment (p < 0.01). The results indicate that algal photosynthesis can have a significant impact on bacterial productivity, biomass, biovolume, and enzyme production over longer time periods at low photon flux densities (?100 mmol m?2 s?1). [ABSTRACT FROM AUTHOR]

Background: Language-concordant health care, or health care in a patient's language of choice, is an important element of health accessibility that improves patient safety and comfort and facilitates an increased quality of care. However, prior research has found that linguistic minorities often face higher travel burdens to access language-concordant care compared to the general population., Objective: This study intended to assess patient experiences and satisfaction with an online interactive physician map that allows patients to find family physicians who speak their preferred language in and around Ottawa, Ontario, Canada, as a means of identifying areas of improvement., Methods: This study used an online survey with questions related to user satisfaction. Responses to Likert-scale questions were compiled as summary statistics and short-answer responses underwent thematic analysis. The study setting was Ottawa and Renfrew County, Ontario, and the surrounding region, including the province of Quebec., Results: A total of 93 respondents completed the survey and self-identified as living in Ontario or Quebec. Overall, 57 (61%) respondents were "very satisfied" or "somewhat satisfied" with the map, 16 (17%) were "neither satisfied nor dissatisfied," and 20 (22%) were "very dissatisfied" or "somewhat dissatisfied." We found no significant differences in satisfaction by preferred language, age group, physician attachment, or intended beneficiary. A total of 56 respondents provided short-answer responses to an open-ended question about map improvements. The most common specific suggestion was to show which physicians are accepting new patients (n=20). Other suggestions included data refreshes (n=6), user interface adjustments (n=23), and additional languages (n=2). Some participants also provided positive feedback (n=5) or expressed concern with their inability to find a family physician (n=5). Several comments included multiple suggestions., Conclusions: While most patients were satisfied with the online map, a significant minority expressed dissatisfaction that the map did not show which family physicians were accepting new patients. This suggests that there may be public interest in an accessible database of which family physicians in Ontario are currently accepting new patients., (©Christopher Belanger, Cayden Peixoto, Sara Francoeur, Lise M Bjerre. Originally published in JMIR Formative Research (https://formative.jmir.org), 09.07.2024.)

The hyperbolic dispersion relation of phonon-polaritons (PhPols) in anisotropic van der Waals materials provides high-momentum states, directional propagation, subdiffractional confinement, large optical density of states, and enhanced light-matter interactions. In this work, we use Raman spectroscopy in the convenient backscattering configuration to probe PhPol in GaSe, a 2D material presenting two hyperbolic regions separated by a double reststrahlen band. By varying the incidence angle, dispersion relations are revealed for samples with thicknesses between 200 and 750 nm. Raman spectra simulations confirm the observation of one surface and two extraordinary guided polaritons and match the evolution of PhPol frequency as a function of vertical confinement. GaSe appears to provide relatively low propagation losses and supports confinement factors matching or exceeding those reported for other 2D materials. Resonant excitation close to the 1s exciton singularly exalts the scattering efficiency of PhPols, providing enhanced scattering signals and means to probe the coupling of PhPols to other solid-state excitations., (© 2023. The Author(s).)

A novel method of detecting extracellular protease activity at biofilm-substratum interfaces was developed. This method utilizes fluorescent molecules bound to cellulose substrata with a lectin. Extracellular proteases degrade the lectin and release the fluorochrome into solution. This new technique and a standard dissolved-substrate assay detected similar responses of biofilm extracellular protease activity to experimental manipulation of N supply. Combination of this technique with confocal scanning laser microscopy allowed direct visualization of microspatial patterns of bacterial distribution and extracellular protease activity at the biofilm-substratum interface.