Collaborating to support the use and development of open educational resources: a White Rose Libraries research project

Interest in open educational resources (OER) has grown recently due to many external factors, including the restrictive, unsustainable and expensive business models for teaching materials that are being used by some publishers. In February 2021, the libraries of the UK White Rose University Consortium (White Rose Libraries) initiated a research project to explore the potential of OER and to create guidance in the form of an OER toolkit that could be used across all three institutions, and more widely. The project also aimed to seek improvements in the discovery of OER in the Ex Libris Primo discovery service which is used by all three libraries. This article outlines the methodology used to ascertain the needs of the libraries’ user groups to inform the development of the toolkit. A survey of academic staff across all three institutions was conducted, followed by user experience interviews. The survey findings established that more than half of respondents knew little or nothing about OER, and over half also said that they would be likely or extremely likely to consider using or adapting OER, clearly demonstrating the need for more awareness raising and guidance. The survey interview findings were then used to develop and refine the toolkit

The nature of the silicaphilic fluorescence of PDMPO

PDMPO (2-(4-pyridyl)-5-((4-(2-dimethylaminoethylaminocarbamoyl)methoxy)phenyl)oxazole), has unique silica specific fluorescence and is used in biology to understand biosilicification. This ‘silicaphilic’ fluorescence is not well understood nor is the response to local environmental variables like solvent and pH. We investigated PDMPO in a range of environments: using UV-vis and fluorescence spectroscopy supported by computational data, (SPARC, molecular dynamics simulations, density functional theory calculations), dynamic light scattering and zeta potential measurements to understand the PDMPO–silica interaction. From absorption data, PDMPO exhibited a pKa of 4.20 for PDMPOH22+ to PDMPOH+ . Fluorescence emission measurements revealed large shifts in excited state pKa* values with different behaviour when bound to silica (pKa* of 10.4). PDMPO bound to silica particles is located in the Stern layer with the dye exhibiting pH dependent depolarising motion. In aqueous solution, PDMPO showed strong chromaticity with correlation between the maximum emission wavelength for PDMPOH+* and dielectric constant (4.8–80). Additional chromatic effects were attributed to changes in solvent accessible surface area. Chromatic effects were also observed for silica bound dye which allow its use as a direct probe of bulk pH over a range far in excess of what is possible for the dye alone (3–5.2). The unique combination of chromaticity and excited state dynamics allows PDMPO to monitor pH from 3 to 13 while also reporting on surface environment opening a new frontier in the quantitative understanding of (bio)silicification

Hematopoietic stem cell transplantation for Wiskott-Aldrich syndrome: an EBMT Inborn Errors Working Party analysis

Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative treatment for patients affected by Wiskott-Aldrich syndrome (WAS). Reported HSCT outcomes have improved over time with respect to overall survival, but some studies have identified older age and HSCT from alternative donors as risk factors predicting poorer outcome. We analyzed 197 patients undergoing transplant at European Society for Blood and Marrow Transplantation centers between 2006 and 2017 who received conditioning as recommended by the Inborn Errors Working Party (IEWP): either busulfan (n = 103) or treosulfan (n = 94) combined with fludarabine 6 thiotepa. After a median follow-up post-HSCT of 44.9 months, 176 patients were alive, resulting in a 3-year overall survival of 88.7% and chronic graft-versus-host disease (GVHD)-free survival (events include death, graft failure, and severe chronic GVHD) of 81.7%. Overall survival and chronic GVHD-free survival were not significantly affected by conditioning regimen (busulfan-vs treosulfan-based), donor type (matched sibling donor/matched family donor vs matched unrelated donor/mismatched unrelated donor vs mismatched family donor), or period of HSCT (2006-2013 vs 2014-2017). Patients aged = 5 years remains a risk factor for overall survival.Transplantation and immunomodulatio

Possible role of ubiquitin in silica biomineralization in diatoms:identification of a homologue with high silica affinity

In diatom silicon biomineralization peptides are believed to play a role in silica precipitation and the consequent structure direction of the cell wall. Characterization of such peptides should reveal the nature of this organic-inorganic interaction, knowledge that may eventually well be used to expand the existing range of artificial silicas ("biomimicking"). Biochemical studies on Navicula pelliculosa revealed a set of proteins, which have a high affinity for a solid silica matrix; some were only eluted from the matrix when SDS-denaturation was applied. One of the proteins with an affinity for silica, about 8.5 kDa, is shown to be a homologue of ubiquitin on the basis of its N-terminal amino acid sequence; ubiquitin itself is a highly conserved 8.6 kDa protein that is involved in protein degradation. This finding is in line with a model of silica biomineralization in diatoms that implies the removal of templating polypeptides when pores in the growing cell wall develop. Western blotting with specific anti-ubiquitin antibodies confirmed cross-reactivity. Immunocytochemical localization of ubiquitin indicates that it is present along the diatom cell wall and inside pores during different stages of valve formation. (C) 2003 Elsevier Science B.V. All rights reserved

The impact of organ-at-risk contour variations on automatically generated treatment plans for NSCLC

Background and purpose: Quality of automatic contouring is generally assessed by comparison with manual delineations, but the effect of contour differences on the resulting dose distribution remains unknown. This study evaluated dosimetric differences between treatment plans optimized using various organ-at-risk (OAR) contouring methods.Materials and methods: OARs of twenty lung cancer patients were manually and automatically contoured, after which user-adjustments were made. For each contour set, an automated treatment plan was generated. The dosimetric effect of intra-observer contour variation and the influence of contour variations on treatment plan evaluation and generation were studied using dose-volume histogram (DVH)parameters for thoracic OARs.Results: Dosimetric effect of intra-observer contour variability was highest for Heart D-max (3.4 +/- 6.8 Gy) and lowest for Lungs-GTV D-mean (0.3 +/- 0.4 Gy). The effect of contour variation on treatment plan evaluation was highest for Heart D-max (6.0 +/- 13.4 Gy) and Esophagus D-max (8.7 +/- 17.2 Gy). Dose differences for the various treatment plans, evaluated on the reference (manual) contour, were on average below 1 Gy/1%. For Heart D-mean, higher dose differences were found for overlap with PTV (median 0.2 Gy, 95% 1.7 Gy) vs. no PTV overlap (median 0 Gy, 95% 0.5 Gy). For D-max-parameters, largest dose difference was found between 0-1 cm distance to PTV (median 1.5 Gy, 95% 4.7 Gy).Conclusion: Dose differences arising from automatic contour variations were of the same magnitude or lower than intra-observer contour variability. For Heart D-mean, we recommend delineation errors to be corrected when the heart overlaps with the PTV. For D-max-parameters, we recommend checking contours if the distance is close to PTV (<5 cm). For the lungs, only obvious large errors need to be adjusted. (C) 2021 The Authors. Published by Elsevier B.V

PEG-mediated silica pore formation monitored in situ by USAXS and SAXS:Systems with properties resembling diatomaceous silica

Poly(ethylene glycol) (PEG) was employed as templating agent for the synthesis of porous silica. The effect of PEG chain length and of the PFG/silica ratio on textural properties (fractality, pore size, and pore distribution) were investigated by monitoring the development of silica-PEG intermediates using ultrasmall and small-angle X-ray scattering analysis with high-brilliance synchrotron radiation to obtain sufficient radiation intensity for dynamic results at the subminute scale. We show that even a simple structure-directing polymer, such as PEG, results in silicas with pores of diameters spanning a range of less than 2 nm up to 20 nm, depending on polymer molecule length and polymer/silica ratio. Flocculation may well be the most important distinction between silicas prepared with small and large PEG. In this view, small PEG600 gets encapsulated by silica and forms pools within the silica framework, whereas large PEG20,000 is entangled in a mass of silica spheres, making enclosure by silica or phase separation impossible. Both polymer chain length and the polymer/silica ratio govern the relative importance of flocculation, phase separation, and hydrophobic silica-PEG interactions steering the silica polymerization. Increase in hydrophobicity results in a larger surface area and a more uniform pore size distribution, art effect confirmed by scanning electron microscopy (SEM) and observations of physical adsorption of nitrogen gas (BET). Polymers, such as PEG, may well be an inexpensive and versatile substitute and model for polypeptides known as structure-directing agents in biomineralization if silicas resembling natural ones, notably the ones present in such a huge diversity in algae of the group of diatoms, are the focus of scientific attention, e.g., for biomimicking with a view on industrial applications

Silicon biomineralisation: towards mimicking biogenic silica formation in diatoms

A review of research efforts in approaches and the anal. of the way the formation of silica proceeds in diatoms, a process that is expected to inspire new approaches in silica biomimicking. The biochem. and physicochem. characteristics of diatomaceous silica are discussed

Ultrasmall, small, and wide angle X-ray scattering analysis of diatom biosilica: interspecific differences in fractal properties

Freshly prepd. acid-cleaned biosilica of 21 different diatom species was studied using a combination of wide, small, and ultrasmall angle X-ray scattering anal. (WAXS, SAXS, and USAXS) in order to det. whether the structural and fractal properties from the subnanometer level up to dimensions of several microns are species-specific, and if so to quantify them. WAXS data are in line with the amorphous nature of this kind of biosilica: no Bragg reflections were obsd. at the level below 1 nm. Straight domains in the scattering spectra (in both SAXS and USAXS) revealed the presence of different fractal regions with highly species-specific transition points, as part of the surface structure. All silica specimens had four of these fractal regions, but with a length scale per region characteristic for each specimen except for the region (Region I) covering the WAXS domain (d &lt;1.5 nm). In this first region no fractal behavior was obsd. for the amorphous biosilica. Region II, with a fractal dimension (Ds) over 3.8, which indicates a smooth surface, covered the lower SAXS domain (1.5 &lt;d &lt;10 nm). Region III (3.3 &lt;Ds &lt;3.8), in the upper SAXS and lower USAXS domain (10 &lt;d &lt;396 nm), represented a rougher surface, whereas Region IV (Ds &lt;2.8), the upper USAXS domain (d &gt; 396 nm), revealed the roughest surface. Transition points between straight regions in the scattering spectra did relate to the dimension of meso- and macro-pores that are known to be present in diatom biosilica; the pore sizes detd. from the spectra agreed with ests. made from electron micrographs. Interestingly, dominant scattering peaks were obsd. in USAXS, as if we were dealing with crystals as in highly ordered MCM-type silicas. This crystallinity was only apparent, not real; it is most probably due to the high regularity in pore distributions in diatom biosilica in the size range of 100 to .apprx.500 nm. Our data show that diatom biosilica has quantifiable species-specific fractal surface properties, next to the well known species-specific pore architecture that is well beyond those of other well-ordered artificial silica materials. Consequently, it is likely that each also has its own surface pattern of reactive sites and in view of these large variations each diatom species potentially can be the source for the design of a different silica-based materia