2,225 research outputs found

    Alkali oxide-tantalum, niobium and antimony oxide ionic conductors

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    The phase equilibrium relations of four systems were investigated in detail. These consisted of sodium and potassium antimonates with antimony oxide and tantalum and niobium oxide with rubidium oxide as far as the ratio 4Rb2O:llB2O5 (B=Nb, Ta). The ternary system NaSbO3-Sb2O4-NaF was investigated extensively to determine the actual composition of the body centered cubic sodium antimonate. Various other binary and ternary oxide systems involving alkali oxides were examined in lesser detail. The phases synthesized were screened by ion exchange methods to determine mobility of the mobility of the alkali ion within the niobium, tantalum or antimony oxide (fluoride) structural framework. Five structure types warranted further investigation; these structure types are (1) hexagonal tungsten bronze (HTB), (2) pyrochlore, (3) the hybrid HTB-pyrochlore hexagonal ordered phases, (4) body centered cubic antimonates and (5) 2K2O:3Nb2O5. Although all of these phases exhibit good ion exchange properties only the pyrochlore was prepared with Na(+) ions as an equilibrium phase and as a low porosity ceramic. Sb(+3) in the channel interferes with ionic conductivity in this case, although relatively good ionic conductivity was found for the metastable Na(+) ion exchanged analogs of RbTa2O5F and KTaWO6 pyrochlore phases

    Realising governmentality: pastoral power, governmental discourse and the (re)constitution of subjectivities

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    Michel Foucault’s concept of governmentality has been hugely influential in sociology and other disciplinary fields. However, its application has been criticised by those who suggest it neglects agency, and gives overwhelming power to governmental discourses in constituting subjectivities, determining behaviour, and reproducing social reality. Drawing on posthumously translated lecture transcripts, we suggest that Foucault’s nascent concept of pastoral power offers a route to a better conceptualisation of the relationship between discourse, subjectivity and agency, and a means of understanding the (contested, non-determinate, social) process through which governmental discourses are shaped, disseminated, and translated into action. We offer empirical examples from our work in healthcare of how this process takes place, present a model of the key mechanisms through which contemporary pastoral power operates, and suggest future research avenues for refining, developing or contesting this model

    Unlearning and patient safety

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    This chapter adds to the growing body of literature on unlearning by contributing a model applicable to the context of professional organisations, and more specifically to healthcare and patient safety. An overview of the global patient safety agenda is described and a gap in implementing sustained safety improvement identified. The UK’s efforts to bridge this gap in patient safety by transforming their NHS into a ‘learning organisation’ are discussed. The unlearning literature is reviewed and an updated model of unlearning conceptualized that contains three dimensions relevant to the study of professionals: cognitive, cultural and political. As a research agenda, this chapter provides a starting point for thinking about how unlearning can be studied in organisations; establishing a theoretical foundation for future study

    The right-to-manage default rule

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    We critically examine the right-to-manage as a legal default rule. We then assess the merits of alternative process and content defaults, as well as non-waivable terms and conditions. Finally, we suggest how various options might be combined in different circumstances

    AI as a Medical Device Adverse Event Reporting in Regulatory Databases: Protocol for a Systematic Review

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    \ua9Aditya U Kale, Riya Dattani, Ashley Tabansi, Henry David Jeffry Hogg, Russell Pearson, Ben Glocker, Su Golder, Justin Waring, Xiaoxuan Liu, David J Moore, Alastair K Denniston. Originally published in JMIR Research Protocols.Background: The reporting of adverse events (AEs) relating to medical devices is a long-standing area of concern, with suboptimal reporting due to a range of factors including a failure to recognize the association of AEs with medical devices, lack of knowledge of how to report AEs, and a general culture of nonreporting. The introduction of artificial intelligence as a medical device (AIaMD) requires a robust safety monitoring environment that recognizes both generic risks of a medical device and some of the increasingly recognized risks of AIaMD (such as algorithmic bias). There is an urgent need to understand the limitations of current AE reporting systems and explore potential mechanisms for how AEs could be detected, attributed, and reported with a view to improving the early detection of safety signals. Objective: The systematic review outlined in this protocol aims to yield insights into the frequency and severity of AEs while characterizing the events using existing regulatory guidance. Methods: Publicly accessible AE databases will be searched to identify AE reports for AIaMD. Scoping searches have identified 3 regulatory territories for which public access to AE reports is provided: the United States, the United Kingdom, and Australia. AEs will be included for analysis if an artificial intelligence (AI) medical device is involved. Software as a medical device without AI is not within the scope of this review. Data extraction will be conducted using a data extraction tool designed for this review and will be done independently by AUK and a second reviewer. Descriptive analysis will be conducted to identify the types of AEs being reported, and their frequency, for different types of AIaMD. AEs will be analyzed and characterized according to existing regulatory guidance. Results: Scoping searches are being conducted with screening to begin in April 2024. Data extraction and synthesis will commence in May 2024, with planned completion by August 2024. The review will highlight the types of AEs being reported for different types of AI medical devices and where the gaps are. It is anticipated that there will be particularly low rates of reporting for indirect harms associated with AIaMD. Conclusions: To our knowledge, this will be the first systematic review of 3 different regulatory sources reporting AEs associated with AIaMD. The review will focus on real-world evidence, which brings certain limitations, compounded by the opacity of regulatory databases generally. The review will outline the characteristics and frequency of AEs reported for AIaMD and help regulators and policy makers to continue developing robust safety monitoring processes

    Effect of tissue phosphorus concentration on the mineralisation of nitrogen from stylo and cowpea residues

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    Laboratory studies were conducted to investigate the effect of phosphorus concentration in residues of cowpea (t Vigna unguiculata, L. Walp) and stylo (t Stylosanthes hamata, L., cv Verano) on their rate of nitrogen mineralisation when incubated in a soil whose P status was deficient for plant growth. Residues with a range of P concentrations were obtained by applying varying rates of P to soil in which the plants were grown in the field or the glasshouse. Variations in P concentration of field- or glasshouse-grown residues were not accompanied by variations in other chemical components (C:N ratio, lignin and polyphenol concentrations). Both lignin and polyphenol concentrations were higher in the field-grown than in the glasshouse-grown residues. Lignin concentration was greater in cowpea than in stylo, but polyphenols were higher in stylo. Cowpea residues mineralised N less rapidly than stylo. N mineralisation from residues with low P concentration was consistently less than from those of higher P concentration; reduced mineralisation was observed for P concentration in the residues below 1.6 g kg−1. When inorganic P was added to the residue-soil systems, N mineralisation from the residues was increased, though no interaction between the effects of adding inorganic P and P concentration in the residues was observe

    The Role of Repeated Exposure to Multimodal Input in Incidental Acquisition of Foreign Language Vocabulary

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    Prior research has reported incidental vocabulary acquisition with complete beginners in a foreign language (FL), within 8 exposures to auditory and written FL word forms presented with a picture depicting their meaning. However, important questions remain about whether acquisition occurs with fewer exposures to FL words in a multimodal situation and whether there is a repeated exposure effect. Here we report a study where the number of exposures to FL words in an incidental learning phase varied between 2, 4, 6, and 8 exposures. Following the incidental learning phase, participants completed an explicit learning task where they learned to recognize written translation equivalents of auditory FL word forms, half of which had occurred in the incidental learning phase. The results showed that participants performed better on the words they had previously been exposed to, and that this incidental learning effect occurred from as little as 2 exposures to the multimodal stimuli. In addition, repeated exposure to the stimuli was found to have a larger impact on learning during the first few exposures and decrease thereafter, suggesting that the effects of repeated exposure on vocabulary acquisition are not necessarily constant

    Wildfire alters the structure and seasonal dynamics of nocturnal pollen‐transport networks

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    Wildfires drive global biodiversity patterns and affect plant–pollinator interactions, and are expected to become more frequent and severe under climate change. Post-fire plant communities often have increased floral abundance and diversity, but the effects of wildfires on the ecological process of pollination are poorly understood. Nocturnal moths are globally important pollinators, but no previous study has examined the effects of wildfire on nocturnal pollination interactions. We investigated the effects of wildfire on nocturnal pollen-transport networks. We analysed the abundance and species richness of moths and flowers, and the structure of these networks, at three burned and three unburned sites in Portugal for two years, starting eight months after a large fire. Nocturnal pollen-transport networks had lower complexity and robustness following the fire than at nearby unburned sites. Overall, 70% of individual moths carried pollen, and moths were found to be transporting pollen from 83% of the flower species present. Burned sites had significantly more abundant flowers, but less abundant and species-rich moths. Individual moths transported more pollen in summer at burned sites, but less in winter; however, total pollen transport by the moth assemblage at burned sites was just 20% of that at unburned sites. Interaction turnover between burned and unburned networks was high. Negative effects of fire upon moths will likely permeate to other taxa through loss of mutualisms. Therefore, if wildfires become more frequent under climate change, community resilience may be eroded. Understanding the responses of ecological networks to wildfire can inform management that promotes resilience and facilitates whole-ecosystem conservation
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