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Identifying variabilities in grain-scale sediment transport thresholds and implications for river stability and form
No full textUnderstanding the processes which define the geometry of gravel bedded river channels is important in predicting their future geomorphological adjustment and addressing contemporary river management challenges in response to climate change (e.g. flood risk). The geometry of stable river channels and the thresholds of channel adjustment can be predicted using an understanding of the mobility of bed material, which is typically quantified using the dimensionless critical shear stress parameter, τ*c. In most applications, τ*c is assumed spatially and temporally constant for a channel reach, which fails to consider the influence of bed material composition and arrangement which are known to vary within a channel and through time. This thesis quantifies the uncertainty of τ*c assumptions in an applied river management context, explores novel approaches towards improving estimates of τ*c at a grain-scale using force-balance approaches, and investigates the spatial and temporal drivers of grain arrangement and mobility.Fundamental hydraulic geometry theory was used to evaluate the uncertainties associated with basic τ*c assumptions in river management contexts. Predictions of channel (dis)equilibrium were obtained by quantifying deviations from expected equilibrium geometry for 45 upland UK channel reaches, and were largely consistent with observed evidence of recent channel adjustment and could therefore give predictive insight into hotspots of geomorphic risk. However, predictions of stable channel geometry were sensitive to small variations in τ*c. To incorporate grain-scale mobility controls such as grain protrusion into estimates of τ*c, force-balance models were tested; these combined grain microtopography data quantified using Structure-from-Motion topography with measurements of particle resistance force (FR/FW) taken in the field. Median estimates of τ*c generated from the force-balance approaches (0.05 - 0.15) were consistent with typical values of τ*c (0.02 - 0.1), but were advantageous because they evaluated a distribution of likely τ*c values for localised patches, rather than a single value for an entire reach. The force-balance methodology could also be automated at no real detriment to the τ*c estimates, albeit further validation is required. To evaluate the spatial controls on bed mobility across different rivers, distributions of FR/FW were compared against metrics of bed texture, including imbrication, sorting and surface roughness. It was found that all sampled beds could be categorised into one of four broad bed types, based on combinations of surface texture and grain shape. Each bed type yielded different FR/FW measurements. For example, well sorted, imbricated surfaces had high FR/FW and were therefore least mobile, whereas poorly sorted, non-imbricated surfaces had low FR/FW and were therefore most mobile. Given that bed texture was an important control on grain mobility, the influence of flow history on the temporal variability of grain arrangement properties was further investigated by repeat sampling an exposed channel bed (River Alport, Peak District) over a nine-month monitoring period. Observations revealed evidence for the self-reorganisation of bed material following large destructive events, following periods of inundation. This gave insight into the timescales of bed recovery, for example, highlighting the role of flood sequencing on the cumulative destruction or restabilisation of river gravels, depending on the timing of flows of varying magnitudes.These findings are important in river management applications, because they can help to develop estimates of τ*c which can better reflect the variability of natural river beds. Further applications of the datasets and approaches outlined in this thesis should be used to develop guidelines which can be used by river managers to adjust τ*c based on easy-to collect qualitative channel bed observations and/or flow history records. This would help to improve evaluations of river channel stability and form over large spatial scales.</p
Media review: organizing serendipity
No full textMedia review of:Christian BuschConnect the dots: The art and science of creating good luckNew York: Penguin Random House, 2022. 392 pp.</p
Henri Matisse and James Joyce: The Limited Editions Club Ulysses as a modernist temporal artefact
No full textThe Limited Editions Club Ulysses occupies a troubled position in histories of the illustrated book. Since the work’s publication in October 1935, critics have debated the extent to which the images that Henri Matisse created for it do or do not relate meaningfully to James Joyce’s text. The weight of critical opinion is that the book was a design failure. The artist’s decision to illustrate selected episodes from Homer’s Odyssey rather than to depict scenes or motifs from the novel led Richard Ellman to conclude that Matisse’s approach was a misstep resulting from limited contact between writer and painter (1982: 675 and 682); William S. Liebermann describes Matisse’s illustrations as ‘slight’ and ‘unsuccessful’ (Liebermann 1957: 12); Willard Goodwin goes so far as to describe the edition as a ‘travesty’ (Goodwin 1999: 86); and John Bidwell regrets that the book was an ‘artistic disappointment’ (Bidwell 2014: 51). Even Joyce distanced himself from the project in the months leading to publication (Joyce 1975: 374–5), and Matisse ultimately omitted the work from his own 1946 essay ‘How I made my books’ (Matisse 2005: 211). [...]</p
Forecasting indoor air temperatures in tropical hospitals to improve patient health and preparedness for extreme heat
No full textExtreme heat is a growing public health threat in tropical Africa, especially in Ghana where outdoor maximum daily temperatures (Tx) regularly exceed 35°C. Vulnerability to heat is socially and economically differentiated, however, with pregnant women, young children, elderly people, and people with chronic health conditions most at risk. High proportions of these groups are found in hospitals, yet little is known about extreme temperatures inside wards. This paper addresses these gaps by developing proof-of-?concept forecasting models for indoor air temperatures in Ghanaian hospital wards. A significant contribution of this work is the novel, high-resolution, empirical indoor environment dataset collected from four hospitals capturing a variety of building types in two distinct climate zones. This dataset enabled the development and testing of heat-?health early warning systems which significantly contributes to a scalable, generalisable framework for climate adaptation in healthcare buildings across the tropical Global South. Measured indoor Tx were statistically related to numerical weather predictions of outdoor temperatures to create models capable of explaining up to 75% of the variance in daily Tx with accuracies of ~1°C at 24 h forecasting times. Such heat alerts could be used by hospital authorities to adjust staffing levels for expected surges in patient volumes, and for rescheduling of elective non-urgent outpatient treatments to free up capacity during heatwaves. However, we assert that heat-health early warning systems should be integrated alongside other measures to adapt to rising indoor temperatures, such as improving hospital design, formulating heat-health action plans, and raising awareness of heat-related health issues.</p
Expert patients and evil technology? Situating users, platforms and expertise in social media health content
No full textBringing together sociological work, science and technologies studies and media and communication research, this chapter covers key concepts and debates to understand the relevance and situatedness of digital media in health information and communication practices initiated by lay users. First, it provides a longitudinal ac- count of the context in which contemporary digital media have become a means through which non-institutional health information is produced, shared, fabricated, contested and/or politicised. In doing so, it traces the gradual emergence of new forms of expertise from the 1970s onwards and illustrates the rise and role of digital media in these developments. This part of the chapter also explores the way these very technologies have intersected with existing social dynamics associated with the circulation of misinformation, disinformation and conspiracy theories. The remainder of the chapter looks more closely at the way contemporary digital media, and main- stream social media in particular, operate as discursive spaces shaped by both the po- litical economy of corporate-driven platform systems and users’ interpretations of, and the tinkering of, these very systems. The concluding remarks suggest future research directions to understand how digital media discourse, use and technology contribute to the shaping of health information, knowledge and expertise.</p
Questionnaire for Participation in the ESRS Conferences: Insights from Early Career Professionals
No full textSupplementary InformationParticipation in the ESRS Conferences: Insights from Early Career ProfessionalsThis supplementary file contains the full study questionnaire (Annexure A) and a detailed overview of the recruitment strategies implemented for the study (Annexure B). The questionnaire includes the participant information sheet, consent form, and all survey items covering demographic characteristics, conference participation history, perceived barriers, accessibility considerations, and recommendations for improving inclusivity in international sleep conferences. Annexure B documents the multi-level dissemination approach used across ESRS committees, national sleep societies, conferences, academic institutions, and professional networks to promote survey participation.© the author</p
TNAP-positive matrix vesicles are enriched in Annexin II and tetraspanins
No full textMatrix vesicles (MVs) provide a specialised niche for the nucleation of biological apatite. While the minerali?sation enabling enzyme tissue non-specific alkaline phosphatase (TNAP) is commonly applied as a marker, its organisation and relative abundance on MVs remains incompletely defined. The relationship between MVs and unbound exosomes/microvesicles recovered from culture media (mEVs) also remains a point of contention. We show that MVs expressed markers of ESCRT (endosomal sorting complexes required for transport) biogenesis common to exosomes/microvesicles, including Alix, TSG101 and CD63. TEM and AFM analysis revealed het?erogeneity in the MV population, with pro-mineralising electron-dense and non-mineralising MVs observed. Few MVs (+ MVs (mean of 82.3%) and mEVs (mean of 72.7%) localised with the calcium channelling protein annexin II. Annexin V (alternative calcium channel) was not upregulated in the TNAP+ fraction. Both MVs and mEVs were capable of mineral nucleation, though only MVs isolated at earlier time points (days 7 and 9) appeared capable of generating hydroxyapatite-like material. In conclusion, we identify for the first time that mineralisation-competent TNAP+ MVs are enriched in annexin II and express common markers of endosomal biogenesis. We show that a TNAP+/annexin II+ population is also present in mEV fractions but only quantifiable using high-resolution techniques. These results provide new insights into the composition of pro-mineralising vesicles and give further credence to the hypothesis that MVs may represent anchored exosomes.</p
Peer effects in classrooms – Evidence from random assignment
No full textWe apply a novel approach to estimate the effects of exposure to peers with different attributes by using the predetermined leave-own-out attributes of all classmates in randomly assigned classes. This strategy allows a behavioural interpretation of the peer effect over and above the pure mechanical channel. We find that being exposed to peer groups with attributes conducive to academic achievements, induced by random variations in the shares of classmates with college-educated parents, increases exam scores. We show that estimates based on the commonly used leave-own-out measures are highly sensitive to sample selection bias arising from non-random tracking in the sample.</p
3674 Setting the research agenda for co-existing dementia and hearing conditions: a James Lind alliance priority setting partnership
No full textThis is an embargoes abstract for the article: 3674 Setting the research agenda for co-existing dementia and hearing conditions: a James Lind alliance priority setting partnership</p