1,609 research outputs found

    Design and development of a solar array drive

    Get PDF
    The design and development of a dry lubricated direct drive solar array pointing mechanism is discussed for use on the Orbital Test Satellite (OTS), MAROTS, European Communication Satellite (ECS), and others. Results of life testing the original prototype and the OTS mechanism are presented together with an appraisal of expected future development

    Efficient preparation and detection of microwave dressed-state qubits and qutrits with trapped ions

    Get PDF
    We demonstrate a method for preparing and detecting all eigenstates of a three-level microwave dressed system with a single trapped ion. The method significantly reduces the experimental complexity of gate operations with dressed-state qubits, as well as allowing all three of the dressed states to be prepared and detected, thereby providing access to a qutrit that is well protected from magnetic field noise. In addition, we demonstrate individual addressing of the clock transitions in two ions using a strong static magnetic field gradient, showing that our method can be used to prepare and detect microwave dressed states in a string of ions when performing multi-ion quantum operations with microwave and radio frequency fields. The individual addressability of clock transitions could also allow for the control of pairwise interaction strengths between arbitrary ions in a string using lasers

    Pharmacokinetics of penicillin G in preterm and term neonates.

    Get PDF
    Group B streptococci are common causative agents of early-onset neonatal sepsis (EOS). Pharmacokinetic (PK) data for penicillin G have been described for extremely preterm neonates but poorly for late-preterm and term neonates. Thus, evidence-based dosing recommendations are lacking. We described PK of penicillin G in neonates with gestational age (GA) ≥32 weeks and postnatal age 90% for MICs ≤2 mg/L with doses of 25,000 IU/kg/q12h. In neonates, regardless of GA, PK parameters of penicillin G are similar. The dose of 25,000 IU/kg/q12h is suggested for treatment of group B streptococcal EOS diagnosed within the first 72 hours of life

    Architects of time: Labouring on digital futures

    Get PDF
    Drawing on critical analyses of the internet inspired by Gilles Deleuze and the Marxist autonomia movement, this paper suggests a way of understanding the impact of the internet and digital culture on identity and social forms through a consideration of the relationship between controls exercised through the internet, new subjectivities constituted through its use and new labour practices enabled by it. Following Castells, we can see that the distinction between user, consumer and producer is becoming blurred and free labour is being provided by users to corporations. The relationship between digital technologies and sense of community, through their relationship to the future, is considered for its dangers and potentials. It is proposed that the internet may be a useful tool for highlighting and enabling social connections if certain dangers can be traversed. Notably, current remedies for the lack of trust on the internet are questioned with an alternative, drawing on Zygmunt Bauman and Georg Simmel, proposed which is built on community through a vision of a ‘shared network’

    Development and evaluation of a gentamicin pharmacokinetic model that facilitates opportunistic gentamicin therapeutic drug monitoring in neonates and infants.

    Get PDF
    Trough gentamicin therapeutic drug monitoring (TDM) is time-consuming, disruptive to neonatal clinical care and a patient safety issue. Bayesian models could allow TDM to be performed opportunistically at the time of routine blood tests. This study aimed to develop and prospectively evaluate a new gentamicin model and a novel Bayesian computer tool (neoGent) for TDM use in neonatal intensive care. We also evaluated model performance for predicting peak concentrations and AUC(0-t). A pharmacokinetic meta-analysis was performed on pooled data from three studies (1325 concentrations from 205 patients). A 3-compartment model was used with covariates being: allometric weight scaling, postmenstrual and postnatal age, and serum creatinine. Final parameter estimates (standard error) were: clearance: 6.2 (0.3) L/h/70kg; central volume (V) 26.5 (0.6) L/70kg; inter-compartmental disposition: Q=2.2 (0.3) L/h/70kg, V2=21.2 (1.5) L/70kg, Q2=0.3 (0.05) L/h/70kg, V3=148 (52.0) L/70kg. The model's ability to predict trough concentrations from an opportunistic sample was evaluated in a prospective observational cohort study that included data from 163 patients with 483 concentrations collected in five hospitals. Unbiased trough predictions were obtained: median (95% confidence interval (CI)) prediction error was 0.0004 (-1.07, 0.84) mg/L. Results also showed peaks and AUC(0-t) could be predicted (from one randomly selected sample) with little bias but relative imprecision with median (95% CI) prediction error being 0.16 (-4.76, 5.01) mg/L and 10.8 (-24.9, 62.2) mg h/L, respectively. NeoGent was implemented in R/NONMEM, and in the freely available TDMx software

    Dualization and subjective employment insecurity: Explaining the subjective employment insecurity divide between permanent and temporary workers across 23 European countries

    Get PDF
    Dualization theory posits that certain institutions cause dualization in the labour market, yet how institutions deepen the subjective insecurity divide between insiders and outsiders has not been examined. This paper examines this question using data from 23 European countries in 2008/9. Results show that the subjective employment insecurity divide between permanent and temporary workers varies significantly across different countries. Corporatist countries, with stronger unions, have larger subjective insecurity divides between permanent and temporary workers. However, this is because permanent workers feel more secure in these countries rather than because temporary workers are more exposed to feelings of insecurity

    The contested and contingent outcomes of Thatcherism in the UK

    Get PDF
    The death of Margaret Thatcher in April 2013 sparked a range of discussions and debates about the significance of her period in office and the political project to which she gave her name: Thatcherism. This article argues that Thatcherism is best understood as a symbolically important part of the emergence of first-phase neoliberalism. It engages with contemporary debates about Thatcherism among Marxist commentators and suggests that several apparently divergent positions can help us now reach a more useful analysis of Thatcherism’s short- and long-term outcomes for British political economy. The outcomes identified include: an initial crisis in the neoliberal project in the UK; the transformation of the party political system to be reflective of the politics of neoliberalism, rather than its contestation; long-term attempts at the inculcation of the neoliberal individual; de-industrialisation and financial sector dependence; and a fractured and partially unconscious working class. In all long-term outcomes, the contribution of Thatcherism is best understood as partial and largely negative, in that it cleared the way for a longer-term and more constructive attempt to embed neoliberal political economy. The paper concludes by suggesting that this analysis can inform current debates on the left of British politics about how to oppose and challenge the imposition of neoliberal discipline today

    Identity and belonging in social learning groups : the importance of distinguishing social, operational and knowledge-related identity congruence

    Get PDF
    Collaborative learning has much to offer but not all learners participate fully and peer groups can be exclusive. The paper examines how belonging or 'congruence' in learning groups is related to identities of gender, age, ethnicity and socio-economic status. A study of student experiences of collaborative learning on three different blended learning courses illustrated how learners negotiate identity congruence with peer groups to belong and engage. An analytical framework that distinguishes social, operational and knowledge-related identity congruence has emerged. Contrary to received wisdom, the social aspect appears least important for learner engagement while knowledge-related identity congruence is fundamental. Some of the consequences of identity incongruence, particularly concerning gender and maturity, are discussed and the paper points towards the pedagogies which might enable identities of group members to shift so that collaborative learning can flourish
    corecore