142 research outputs found
The temporal fragility of infrastructure: Theorizing decay, maintenance, and repair
Recent studies have reconceptualized infrastructure as comprising both material and social processes, thus offering insights into lived experiences, governance, and socio-spatial reordering. More specific attention to infrastructureâs temporality has challenged its supposed inertia and inevitable completeness, leading to an engagement with questions of the dynamics of infrastructure over different phases of its lifespan, and their generative effects. In this paper, we advance these debates through a focus on the processes of decay, maintenance, and repair that characterize such phases of infrastructural life, by exploring how specific infrastructures are materially shaped by, and shape, social, political, and socio-ecological arrangements. Our intervention has two related aims: firstly, to conceptualize decay, maintenance, and repair as both temporal phases of infrastructureâs dynamic materiality and its specific affective conditions; and, secondly, to trace how these phases of infrastructural life rework embodied labor, differentiated citizenship, and socio-ecological relations. We argue that attention to infrastructure's âtemporal fragilityâ elucidates the articulation between everyday capacities and desires to labor, the creation of and demands made by political constituents, and the uneven distribution of opportunities and resources
Advancing human capabilities for water security: A relational approach
We argue that a relational water security framework informed by the capabilities approach offers new ways to consider politics and cultures of water. Each dimension allows us to better contextualize water security beyond just an object (H2O) to be secured for a certain population. Instead, the relational perspective demands a fuller consideration of the political structures and processes through which water is secured, with emphasis on the social relations of access as opposed to simply the politics around water supply. We also attend to cultural dimensions, such as the meanings of water and customary practices that are not easily captured by standardized metrics. By including these dimensions, we necessarily broaden analytical space to evaluate water security as a relational and dynamic process tied to lived experience rather than as solely parameterized conditions in relation to access, quality, or availability of water. We first move to explain our broader conceptualization of water security as linked to human capabilities, then explore in more detail the specific engagements with politics and culture in the sections that follow
Children's claims to knowledge regarding their mental health experiences and practitioners' negotiation of the problem.
The objective was to identify how children's knowledge positions were negotiated in child mental health assessments and how this was managed by the different parties.The child psychiatry data consisted of 28 video-recorded assessments. A conversation analysis was undertaken to examine the interactional detail between the children, parents, and practitioners.The findings indicated that claims to knowledge were managed in three ways. First, practitioners positioned children as 'experts' on their own health and this was sometimes accepted. Second, some children resisted this epistemic position, claiming not to have the relevant knowledge. Third, some children's claims to knowledge were negotiated and sometimes contested by adult parties who questioned their competence to share relevant information about their lives in accordance with the assessment agenda.Through question design, the practitioner was able to position the child as holding relevant knowledge regarding their situation. The child was able to take up this position or resist it in various ways.This has important implications for debates regarding children's competence to contribute to mental health interventions. Children are often treated as agents with limited knowledge, yet in the mental health assessment they are directly questioned about their own lives
Robust smoothing of left-censored time series data with a dynamic linear model to infer SARS-CoV-2 RNA concentrations in wastewater
Wastewater sampling for the detection and monitoring of SARS-CoV-2 has been developed and applied at an unprecedented pace, however uncertainty remains when interpreting the measured viral RNA signals and their spatiotemporal variation. The proliferation of measurements that are below a quantifiable threshold, usually during non-endemic periods, poses a further challenge to interpretation and time-series analysis of the data. Inspired by research in the use of a custom Kalman smoother model to estimate the true level of SARS-CoV-2 RNA concentrations in wastewater, we propose an alternative left-censored dynamic linear model. Cross-validation of both models alongside a simple moving average, using data from 286 sewage treatment works across England, allows for a comprehensive validation of the proposed approach. The presented dynamic linear model is more parsimonious, has a faster computational time and is represented by a more flexible modelling framework than the equivalent Kalman smoother. Furthermore we show how the use of wastewater data, transformed by such models, correlates more closely with regional case rate positivity as published by the Office for National Statistics (ONS) Coronavirus (COVID-19) Infection Survey. The modelled output is more robust and is therefore capable of better complementing traditional surveillance than untransformed data or a simple moving average, providing additional confidence and utility for public health decision making.
La dĂ©tection et la surveillance du SARS-CoV-2 dans les eaux usĂ©es ont Ă©tĂ© dĂ©veloppĂ©es et rĂ©alisĂ©es Ă un rythme sans prĂ©cĂ©dent, mais l'interprĂ©tation des mesures de concentrations en ARN viral, et de leurs variations spatio-temporelles, pose question. En particulier, l'importante proportion de mesures en deçà du seuil de quantification, gĂ©nĂ©ralement pendant les pĂ©riodes non endĂ©miques, constitue un dĂ©fi pour l'analyse de ces sĂ©ries temporelles. InspirĂ©s par un travail de recherche ayant produit un lisseur de Kalman adaptĂ© pour estimer les concentrations rĂ©elles en ARN de SARS-CoV-2 dans les eaux usĂ©es Ă partir de ce type de donnĂ©es, nous proposons un nouveau modĂšle linĂ©aire dynamique avec censure Ă gauche. Une validation croisĂ©e de ces lisseurs, ainsi que d'un simple lissage par moyenne glissante, sur des donnĂ©es provenant de 286 stations d'Ă©puration couvrant l'Angleterre, valide de façon complĂšte l'approche proposĂ©e. Le modĂšle prĂ©sentĂ© est plus parcimonieux, offre un cadre de modĂ©lisation plus flexible et nĂ©cessite un temps de calcul rĂ©duit par rapport au Lisseur de Kalman Ă©quivalent. Les donnĂ©es issues des eaux usĂ©es ainsi lissĂ©es sont en outre plus fortement corrĂ©lĂ©es avec le taux d'incidence rĂ©gional produit par le bureau des statistiques nationales (ONS) Coronavirus Infection Survey. Elles se montrent plus robustes que les donnĂ©es brutes, ou lissĂ©es par simple moyenne glissante, et donc plus Ă mĂȘme de complĂ©ter la surveillance traditionnelle, renforçant ainsi la confiance en l'Ă©pidĂ©miologie fondĂ©e sur les eaux usĂ©es et son utilitĂ© pour la prise de dĂ©cisions de santĂ© publique
Targeted Delivery of Neural Stem Cells to the Brain Using MRI-Guided Focused Ultrasound to Disrupt the Blood-Brain Barrier
Stem cell therapy is a promising strategy to treat neurodegenerative diseases, traumatic brain injury, and stroke. For stem cells to progress towards clinical use, the risks associated with invasive intracranial surgery used to deliver the cells to the brain, needs to be reduced. Here, we show that MRI-guided focused ultrasound (MRIgFUS) is a novel method for non-invasive delivery of stem cells from the blood to the brain by opening the blood brain barrier (BBB) in specific brain regions. We used MRI guidance to target the ultrasound beam thereby delivering the iron-labeled, green fluorescent protein (GFP)-expressing neural stem cells specifically to the striatum and the hippocampus of the rat brain. Detection of cellular iron using MRI established that the cells crossed the BBB to enter the brain. After sacrifice, 24 hours later, immunohistochemical analysis confirmed the presence of GFP-positive cells in the targeted brain regions. We determined that the neural stem cells expressed common stem cell markers (nestin and polysialic acid) suggesting they survived after transplantation with MRIgFUS. Furthermore, delivered stem cells expressed doublecortin in vivo indicating the stem cells were capable of differentiating into neurons. Together, we demonstrate that transient opening of the BBB with MRIgFUS is sufficient for transplantation of stem cells from the blood to targeted brain structures. These results suggest that MRIgFUS may be an effective alternative to invasive intracranial surgery for stem cell transplantation
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Service evaluation suggests variation in clinical care provision in adults with congenital adrenal hyperplasia in the UK and Ireland
Background: Congenital adrenal hyperplasia (CAH) encompasses a rare group of autosomal recessive disorders, characterised by enzymatic defects in steroidogenesis. Heterogeneity in management practices has been observed internationally. The International Congenital Adrenal Hyperplasia registry (IâCAH, https://sdmregistries.org/) was established to enable insights into CAH management and outcomes, yet its global adoption by endocrine centres remains unclear. Design: We sought (1) to assess current practices amongst clinicians managing patients with CAH in the United Kingdom and Ireland, with a focus on choice of glucocorticoid, monitoring practices and screening for associated coâmorbidities, and (2) to assess use of the IâCAH registry. Measurements: We designed and distributed an anonymised online survey disseminated to members of the Society for Endocrinology and Irish Endocrine Society to capture management practices in the care of patients with CAH. Results: Marked variability was found in CAH management, with differences between general endocrinology and subspecialist settings, particularly in glucocorticoid use, biochemical monitoring and comorbidity screening, with significant disparities in reproductive health monitoring, notably in testicular adrenal rest tumours (TARTs) screening (p = .002), sperm banking (p = .0004) and partner testing for CAH (p < .0001). Adoption of the IâCAH registry was universally low. Conclusions: Differences in current management of CAH continue to exist. It appears crucial to objectify if different approaches result in different longâterm outcomes. New studies such as CaHASE2, incorporating standardised minimum datasets including replacement therapies and monitoring strategies as well as longitudinal data collection, are now needed to define bestâpractice and standardise care
Design, manufacture and test for reliable 3D printed electronics packaging
The development of a surrogate modelling approach to aid design of 3D printed electronics packaging structures is presented, alongside a detailed overview of manufacture and reliability of a representative test structure. An overview of the current status in 3D printing in the electronics packaging sector is provided. Subsequently, a surrogate modelling approach for correlating thermomechanical stresses within a package to a number of design parameters is presented. This approach enables the design of a package to be considered in a more insightful manner and can additionally be integrated into condition based monitoring tools capable of enhancing product robustness. An overview of an advanced electronics packaging system capable of 3D printing electronics packages is presented. The system combines inkjet printing and curing of multiple materials, including conductive silver inks, with precision component placement, multi-material dispensing and 3D inspection systems to provide a highly flexible solution for rapid manufacture of electronics packages. Test structures manufactured using the system were subjected to a vigorous set of reliability tests. Details of the test regime and related results are presented. All tests were passed, indicating the robustness of the described manufacturing process. The key originality of the work is that it provides a comprehensive overview of the journey from design assessment an optimisation, through the manufacturing process and on to reliability testing. Areas of novelty in this work are associated with the development of fast, accurate surrogate models able to predict key reliability factors in response to a range of design parameters and insight into the development of a 3D manufacturing system for electronics packaging
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