288 research outputs found

    The selective oxidation of n-butanol to butyraldehyde by oxygen using stable Pt-based nanoparticulate catalysts: an efficient route for upgrading aqueous biobutanol

    Get PDF
    Supported Pt nanoparticles are shown to be active and selective towards butyraldehyde in the base-free oxidation of n-butanol by O2 in an aqueous phase. The formation of butyric acid as a by-product promoted the leaching of Pt and consequently the activity of the catalysts decreased upon reuse. Characterisation showed that the degree to which Pt leached from the catalysts was related to both the metal–support interaction and metal particle size. A catalyst active and stable (<1% metal leaching) in the aqueous reaction medium was obtained when Pt nanoparticles were supported on activated carbon and prepared by a chemical vapour impregnation method. The presence of n-butanol in the aqueous medium is required to inhibit the over oxidation of butyraldehyde to butyric acid. Consequently, high selectivities towards butyraldehyde can only be obtained at intermediate n-butanol conversion

    Orion KL: The hot core that is not a "Hot Core"

    Full text link
    We present sensitive high angular resolution submillimeter and millimeter observations of torsionally/vibrationally highly excited lines of the CH3_3OH, HC3_3N, SO2_2, and CH3_3CN molecules and of the continuum emission at 870 and 1300 Ό\mum from the Orion KL region, made with the Submillimeter Array (SMA). These observations plus recent SMA CO J=3-2 and J=2-1 imaging of the explosive flow originating in this region, which is related to the non-hierarchical disintegration of a massive young stellar system, suggest that the molecular Orion "Hot Core" is a pre-existing density enhancement heated from the outside by the explosive event -- unlike in other hot cores we do not find any self-luminous submillimeter, radio or infrared source embedded in the hot molecular gas. Indeed, we do not observe filamentary CO flow structures or "fingers" in the shadow of the hot core pointing away from the explosion center. The low-excitation CH3_3CN emission shows the typical molecular heart-shaped structure, traditionally named the Hot Core, and is centered close to the dynamical origin of the explosion. The highest excitation CH3_3CN lines are all arising from the northeast lobe of the heart-shaped structure, {\it i. e.} from the densest and most highly obscured parts of the Extended Ridge. The torsionally excited CH3_3OH and vibrationally excited HC3_3N lines appear to form a shell around the strongest submillimeter continuum source. Surprisingly the kinematics of the Hot Core and Compact Ridge regions as traced by CH3_3CN and HC3_3N also reveal filament-like structures that emerge from the dynamical origin. All of these observations suggest the southeast and southwest sectors of the explosive flow to have impinged on a pre-existing very dense part of the Extended Ridge, thus creating the bright Orion KL Hot Core.Comment: Submitted to A&

    Characteristics associated with quality of life among people with drug-resistant epilepsy

    Get PDF
    Quality of Life (QoL) is the preferred outcome in non-pharmacological trials, but there is little UK population evidence of QoL in epilepsy. In advance of evaluating an epilepsy self-management course we aimed to describe, among UK participants, what clinical and psycho-social characteristics are associated with QoL. We recruited 404 adults attending specialist clinics, with at least two seizures in the prior year and measured their self-reported seizure frequency, co-morbidity, psychological distress, social characteristics, including self-mastery and stigma, and epilepsy-specific QoL (QOLIE-31-P). Mean age was 42 years, 54% were female, and 75% white. Median time since diagnosis was 18 years, and 69% experienced ≄10 seizures in the prior year. Nearly half (46%) reported additional medical or psychiatric conditions, 54% reported current anxiety and 28% reported current depression symptoms at borderline or case level, with 63% reporting felt stigma. While a maximum QOLIE-31-P score is 100, participants’ mean score was 66, with a wide range (25–99). In order of large to small magnitude: depression, low self-mastery, anxiety, felt stigma, a history of medical and psychiatric comorbidity, low self-reported medication adherence, and greater seizure frequency were associated with low QOLIE-31-P scores. Despite specialist care, UK people with epilepsy and persistent seizures experience low QoL. If QoL is the main outcome in epilepsy trials, developing and evaluating ways to reduce psychological and social disadvantage are likely to be of primary importance. Educational courses may not change QoL, but be one component supporting self-management for people with long-term conditions, like epilepsy

    Event-related alpha suppression in response to facial motion

    Get PDF
    This article has been made available through the Brunel Open Access Publishing Fund.While biological motion refers to both face and body movements, little is known about the visual perception of facial motion. We therefore examined alpha wave suppression as a reduction in power is thought to reflect visual activity, in addition to attentional reorienting and memory processes. Nineteen neurologically healthy adults were tested on their ability to discriminate between successive facial motion captures. These animations exhibited both rigid and non-rigid facial motion, as well as speech expressions. The structural and surface appearance of these facial animations did not differ, thus participants decisions were based solely on differences in facial movements. Upright, orientation-inverted and luminance-inverted facial stimuli were compared. At occipital and parieto-occipital regions, upright facial motion evoked a transient increase in alpha which was then followed by a significant reduction. This finding is discussed in terms of neural efficiency, gating mechanisms and neural synchronization. Moreover, there was no difference in the amount of alpha suppression evoked by each facial stimulus at occipital regions, suggesting early visual processing remains unaffected by manipulation paradigms. However, upright facial motion evoked greater suppression at parieto-occipital sites, and did so in the shortest latency. Increased activity within this region may reflect higher attentional reorienting to natural facial motion but also involvement of areas associated with the visual control of body effectors. © 2014 Girges et al

    Implementing a digital intervention for managing uncontrolled hypertension in Primary Care: a mixed methods process evaluation

    Get PDF
    Background: A high proportion of hypertensive patients remain above the target threshold for blood pressure, increasing the risk of adverse health outcomes. A digital intervention to facilitate healthcare practitioners (hereafter practitioners) to initiate planned medication escalations when patients’ home readings were raised was found to be effective in lowering blood pressure over 12 months. This mixed-methods process evaluation aimed to develop a detailed understanding of how the intervention was implemented in Primary Care, possible mechanisms of action and contextual factors influencing implementation. Methods: One hundred twenty-five practitioners took part in a randomised controlled trial, including GPs, practice nurses, nurse-prescribers, and healthcare assistants. Usage data were collected automatically by the digital intervention and antihypertensive medication changes were recorded from the patients’ medical notes. A sub-sample of 27 practitioners took part in semi-structured qualitative process interviews. The qualitative data were analysed using thematic analysis and the quantitative data using descriptive statistics and correlations to explore factors related to adherence. The two sets of findings were integrated using a triangulation protocol. Results: Mean practitioner adherence to escalating medication was moderate (53%), and the qualitative analysis suggested that low trust in home readings and the decision to wait for more evidence influenced implementation for some practitioners. The logic model was partially supported in that self-efficacy was related to adherence to medication escalation, but qualitative findings provided further insight into additional potential mechanisms, including perceived necessity and concerns. Contextual factors influencing implementation included proximity of average readings to the target threshold. Meanwhile, adherence to delivering remote support was mixed, and practitioners described some uncertainty when they received no response from patients

    Implementing a digital intervention for managing uncontrolled hypertension in Primary Care: a mixed methods process evaluation.

    Get PDF
    BACKGROUND: A high proportion of hypertensive patients remain above the target threshold for blood pressure, increasing the risk of adverse health outcomes. A digital intervention to facilitate healthcare practitioners (hereafter practitioners) to initiate planned medication escalations when patients' home readings were raised was found to be effective in lowering blood pressure over 12 months. This mixed-methods process evaluation aimed to develop a detailed understanding of how the intervention was implemented in Primary Care, possible mechanisms of action and contextual factors influencing implementation. METHODS: One hundred twenty-five practitioners took part in a randomised controlled trial, including GPs, practice nurses, nurse-prescribers, and healthcare assistants. Usage data were collected automatically by the digital intervention and antihypertensive medication changes were recorded from the patients' medical notes. A sub-sample of 27 practitioners took part in semi-structured qualitative process interviews. The qualitative data were analysed using thematic analysis and the quantitative data using descriptive statistics and correlations to explore factors related to adherence. The two sets of findings were integrated using a triangulation protocol. RESULTS: Mean practitioner adherence to escalating medication was moderate (53%), and the qualitative analysis suggested that low trust in home readings and the decision to wait for more evidence influenced implementation for some practitioners. The logic model was partially supported in that self-efficacy was related to adherence to medication escalation, but qualitative findings provided further insight into additional potential mechanisms, including perceived necessity and concerns. Contextual factors influencing implementation included proximity of average readings to the target threshold. Meanwhile, adherence to delivering remote support was mixed, and practitioners described some uncertainty when they received no response from patients. CONCLUSIONS: This mixed-methods process evaluation provided novel insights into practitioners' decision-making around escalating medication using a digital algorithm. Implementation strategies were proposed which could benefit digital interventions in addressing clinical inertia, including facilitating tracking of patients' readings over time to provide stronger evidence for medication escalation, and allowing more flexibility in decision-making whilst discouraging clinical inertia due to borderline readings. Implementation of one-way notification systems could be facilitated by enabling patients to send a brief acknowledgement response. TRIAL REGISTRATION: ( ISRCTN13790648 ). Registered 14 May 2015

    The state of the Martian climate

    Get PDF
    60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

    RE: pedagogy – after neutrality

    Get PDF
    Within the UK and in many parts of the world, official accounts of what it is to make sense of religion are framed within a rhetorics of neutrality in which such study is premised upon the possibility of dispassionate engagement and analysis. This paper, which is largely theoretical in scope, explores both the affordances and the costs of such an approach which has become ‘black boxed’ on account of the work that it achieves. A series of new orientations within the academy that are broadly associated with post-structuralist philosophies, feminist and post-colonial studies, together with insights from Science and Technology Studies, question the plausibility of these claims for neutrality whilst in turn raising a series of new questions and priorities. It therefore becomes necessary to re-think and re-frame what it is to make sense of religious and cultural difference after neutrality. The gathering and co-ordination of new planes of sense-making that are responsive to an emergent series of epistemological, ontological, and ethical orientations are considered. Some of the distinctive pedagogical implications of such an approach that engages material practice, difference and uncertainty are then entertained
    • 

    corecore