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Barkcloths, non-woven textiles originating from the Pacific Islands, form part of many museum collections and date back to the 18th and 19th centuries. The ability to determine different plant species which have been used for producing barkcloth is required by art historians to help understand the origin and use of the cloths and by conservators for whom the species type may have an impact on textile durability, deterioration and hence conservation. However, to date the development of a non-destructive, robust analytical technique has been elusive. This article describes the use of Fourier transform infrared spectroscopy with attenuated total reflection (ATR-FTIR) and principal component analysis (PCA) todifferentiation between historic barkcloths. Three distinct groups of historic cloths were identified using PCA of the FTIR region between 1200 and 1600 cm−1 where molecular vibrations associated with tannins and lignins are dominant. Analysis of contemporary cloths only identified Pipturus albidus cloth as different and highlighted the difficulties around producing a representative textile sample to mimic the historic cloths. While the methodology does not itself identify species, the use of historically well-provenanced samples allows cloths showing similarities to group together and is a significant aid to identification.

To explore the experiences, wishes, fears, and beliefs of people who requested and were eligible for medical assistance in dying (MAID) in Canada in the first year after legalization.Qualitative study using semistructured interviews.A clinic in Vancouver, BC, that provides MAID.People requesting and eligible for MAID between February 6 and December 17, 2016. Family and friends who were identified as the patients' primary support people were also interviewed.Semistructured interviews were conducted over the telephone, by e-mail, or in person. The interviews were audiorecorded and transcribed and then analyzed using thematic qualitative analysis. The investigators read the transcripts and created a coding scheme to identify themes in the patients' experiences. The identified themes were compiled and evaluated in the context of what is already known based on current literature. Basic demographic characteristics were recorded for context.Of the 23 patients whose experiences were explored, most had a malignancy, a neurologic disorder, or organ failure. A main theme was that patients thought it was important to have autonomy and control over their own end-of-life decisions. Main reasons for requesting MAID were a self-perceived unacceptable quality of life, most commonly owing to loss of independence, mobility, ability to communicate, a sense of purpose, and participation in meaningful activity. Some people expressed fear of future suffering and future disability. Pain was seldom mentioned as a cause of suffering. Some participants believed they could discuss their decision with the people in their lives while others chose to keep it a private matter. Most people were not religious.The participants' reasons for choosing to pursue MAID were consistent with those of people in other jurisdictions that have been studied. They felt confident in their decision to pursue MAID and did not have fears about the process.

Monitoring the interaction of biomolecules is important, and the use of energy transfer is a principal technique in elucidating nanoscale interactions. Lanthanide compounds are promising luminescent probes for biological samples as their emission is longer-lived than any native autofluorescence. Polyoxometalates (POMs) are interesting structural motifs to incorporate lanthanides, offering low toxicity and a size pertinent for biological applications. Here, we employ iso-structured POMs containing either terbium or europium and assess their interaction with serum albumin by sensitisation of a fluorescent tag on the protein via LRET (luminescence resonance energy transfer) by exciting the lanthanide. Time-resolved measurements showed energy transfer with an efficiency of over 90 % for the POM–protein systems. The Tb–POM results were relatively straightforward, while those with the iso-structured Eu–POM were complicated by the effect of protein shielding from the aqueous environment.

Arrays of nanoantennas consisting of plasmonic dipole pairs have been widely used in surface-enhanced Raman spectroscopy (SERS). Fine-tuned structures that can efficiently convert incident electromagnetic energy to excite molecules and provide enhanced detection. However, this tuning mechanism also has its disadvantages. In order to prevent the cross coupling, the distance between each individual element must be increased. This leads to low packing density values which in turn results in a reduction of the overall enhanced Raman signal when these structures are compared to broadly tuned aggregates of particles such as those obtained through metal sputtering or colloidal deposition. In this work we demonstrate through simulations and experimental work that it is possible to increase the reflected signal of an array of nanoantennas by reducing the distance between them in the direction both perpendicular and parallel to the orientation of the incident electric field. It is shown the resonant wavelength shifts in two different spectral directions depending in how the intercell distance was reduced. These resultant shifts can reduce the tuning capabilities of the structures but also can increase the SERS intensity due to close coupling of the dipole pairs. We believe that these results will enable the design and fabrication of structures possessing a greater degree of tunability together with an overall enhanced Raman signal that can rival aggregated SERS substrates.

Fluorescence microscopy provides a non-invasive means for visualising dynamic protein interactions. As well as allowing the calculation of kinetic processes via the use of time-resolved fluorescence, localisation of the protein within cells or model systems can be monitored. These fluorescence lifetime images (FLIM) have become the preferred technique for elucidating protein dynamics due to the fact that the fluorescence lifetime is an absolute measure, in the main independent of fluorophore concentration and intensity fluctuations caused by factors such as photobleaching. In this work we demonstrate the use of a time-resolved fluorescence microscopy, employing a high repetition rate laser excitation source applied to study the influence of a metal surface on fluorescence tagged protein and to elucidate viscosity using the fluorescence lifetime probe DASPMI. These were studied in a cellular environment (yeast) and in a model system based on a sol-gel derived material, in which silver nanostructures were formed in situ using irradiation from a semiconductor laser in CW mode incorporated on a compact time-resolved fluorescence microscope (HORIBA Scientific DeltaDiode and DynaMyc).