ProSight PTM 2.0: improved protein identification and characterization for top down mass spectrometry

ProSight PTM 2.0 (http://prosightptm2.scs.uiuc.edu) is the next generation of the ProSight PTM web-based system for the identification and characterization of proteins using top down tandem mass spectrometry. It introduces an entirely new data-driven interface, integrated Sequence Gazer for protein characterization, support for fixed modifications, terminal modifications and improved support for multiple precursor ions (multiplexing). Furthermore, it supports data import and export for local analysis and collaboration

Stronger together: learning from an interdisciplinary Dementia, Arts & Wellbeing Network (DA&WN)

There is increasing interest in the use of arts and creative activity to enhance dementia care (e.g. Beard, 2012; Cowl & Gaugler, 2014; Young, Camic & Tischler, 2016), and to bring together and support professionals and those who use services, see Creative Practice as Mutual Recovery (2018). Over the past decade a growing body of research has established this interdisciplinary field of study and there are strategic moves to embed the arts in healthcare more widely (All-Party Parliamentary Group for Arts, Health and Wellbeing, 2017). However, existing research and arts practice have often proceeded in parallel with practitioners criticised for not providing evidence of efficacy, and researchers berated for not working collaboratively with artists (Zeilig & West, in press) and not involving people living with dementia in the co-design of research

Identification of carbon dioxide in an exoplanet atmosphere

Carbon dioxide (CO2) is a key chemical species that is found in a wide range of planetary atmospheres. In the context of exoplanets, CO2 is an indicator of the metal enrichment (that is, elements heavier than helium, also called ‘metallicity’), and thus the formation processes of the primary atmospheres of hot gas giants. It is also one of the most promising species to detect in the secondary atmospheres of terrestrial exoplanets. Previous photometric measurements of transiting planets with the Spitzer Space Telescope have given hints of the presence of CO2, but have not yielded definitive detections owing to the lack of unambiguous spectroscopic identification. Here we present the detection of CO2 in the atmosphere of the gas giant exoplanet WASP-39b from transmission spectroscopy observations obtained with JWST as part of the Early Release Science programme. The data used in this study span 3.0–5.5 micrometres in wavelength and show a prominent CO2 absorption feature at 4.3 micrometres (26-sigma significance). The overall spectrum is well matched by one-dimensional, ten-times solar metallicity models that assume radiative–convective–thermochemical equilibrium and have moderate cloud opacity. These models predict that the atmosphere should have water, carbon monoxide and hydrogen sulfide in addition to CO2, but little methane. Furthermore, we also tentatively detect a small absorption feature near 4.0 micrometres that is not reproduced by these models

Size-Dependent Photoionization in Single CdSe/ZnS Nanocrystals

Fluorescence intermittency in single semiconductor nanocrystals has been shown to follow power law statistics over many decades in time and in probability. Recently, several studies have shown that, while “off” dwell times are insensitive to almost all experimental parameters, “on” dwell times exhibit a pump-power dependent exponential truncation at long times, suggestive of enhanced biexciton photoionization probabilities at high excitation powers. Here we report the dependence of this on-time truncation on nanocrystal radius. We observe a decrease in the per-pulse photoionization probability from 1.8(2) × 10^–4 to 2.0(7) × 10^–6 as the CdSe core radius increases from 1.3 to 3.5 nm, with a radius scaling for the probability for charge ejection arising from biexciton formation <i>P</i>_ionize(<i>r</i>) ∝ 1/<i>r</i>^3.5(5). Effective mass calculations of the exciton wave functions show that the product of fractional electron and hole probabilities in the trap-rich ZnS shell scale similarly with nanocrystal radius. Possible charge ejection mechanisms from such a surface-localized state are discussed