The electron plasma - Experiment theory and applications

Production, stability, and control of pure electron and electron rich plasmas - crossed field electron bea

Experiments on the injection and containment of electron clouds in a toroidal apparatus

Injection and containment of electron clouds in azimuthally symmetric, toroidal apparatu

The production of BeV potential wells

Production of billion electron volt potential wells by cloud of electrons suspended in magnetic fiel

Beyond ‘ignorance’: using the cultural stereotypes of Americans studying in the UK as a resource for learning and teaching about British culture

A course introducing British culture is a standard component of many study abroad programmes running in this country that are aimed at international students who will be spending a limited amount of time in the United Kingdom. However, it is not often acknowledged that such students possess a range of strong pre-conceptions about British culture and society prior to their arrival. Conventional teaching strategies assume student ignorance of the subject. However, an alternative approach which makes us of pre-arrival stereotypes can be more productive in terms of engaging students in active processes of comparative analysis of their new and existing knowledge. A case study of American student stereotypes of the British monarchy is presented and it is suggested that these can be used as the basis for refining student understanding of cultural politics in the United Kingdom. International students, therefore, should not be treated as being culturally ignorant of Britain in the sense of having no knowledge or opinions at all. Rather, it should be understood that they possess a culturally mediated state of subjectivity which I refer to as ‘ignorance’ and that this can become a valuable resource for teaching and learning

Improving bank erosion modelling at catchment scale by incorporating temporal and spatial variability

Bank erosion can contribute a significant portion of the sediment budget within temperate catchments, yet few catchment scale models include an explicit representation of bank erosion processes. Furthermore, representation is often simplistic resulting in an inability to capture realistic spatial and temporal variability in simulated bank erosion. In this study, the sediment component of the catchment scale model SHETRAN is developed to incorporate key factors influencing the spatio-temporal rate of bank erosion, due to the effects of channel sinuosity and channel bank vegetation. The model is applied to the Eden catchment, north-west England, and validated using data derived from a GIS methodology. The developed model simulates magnitudes of total catchment annual bank erosion (617 - 4063 t yr-1) within the range of observed values (211 - 4426 t yr-1). Additionally the model provides both greater inter-annual and spatial variability of bank eroded sediment generation when compared with the basic model, and indicates a potential 61% increase of bank eroded sediment as a result of temporal flood clustering. The approach developed within this study can be used within a number of distributed hydrologic models and has general applicability to temperate catchments, yet further development of model representation of bank erosion processes is required

Cerebrovascular risk in restless legs syndrome: Intima-media thickness and cerebral vasomotor reactivity: A case\u2013control study

Purpose: Although some studies have suggested an association between cardiovascular disease and restless legs syndrome (RLS), the mechanisms underlying this relationship remain unclear. The intima-media thickness (IMT) and vasomotor reactivity are two simple, non-invasive tools to investigate preclinical atherosclerosis and microangiopathy, respectively. The aims of this study were to evaluate carotid IMT and to explore vasomotor reactivity in idiopathic RLS (iRLS) patients. Patients and Methods: We enrolled 44 iRLS after exclusion of patients with secondary causes of RLS, history of vascular events, known uncontrolled vascular risk factors and other neurological disorders. Forty-four age and sex matched controls were therefore recruited. No significant differences in demographic data and vascular risk factors were found between the two groups. Carotid IMT was measured with a high-resolution B-mode ultrasound on the far-wall of common carotid artery, 10 mm and 30 mm to the carotid bulb. Vasomotor reactivity to hypo-and hypercapnia was assessed, by right middle cerebral artery transcranial Doppler, accordingly to the changes in peak systolic velocity, peak diastolic velocity and mean blood flow velocity. Results: Mean IMT was significantly increased in patients with iRLS when measured immediately proximally to carotid bifurcation (0.73; sd=0.17), versus controls (0.65; sd=0.13); p=0.035. Patients showed higher cerebrovascular flow velocities (CBFVs) compared to controls. After multivariate analysis, age, hypertension and iRLS proved to be independent IMT predictors. Conclusion: Increased IMT and higher CBFVs in iRLS support the association of iRLS with vascular damage, possibly through enhanced atherogenesis and sympathetic hyperactivity. However, to clarify a causal relationship, further longitudinal assessment of these parameters is needed, trying to control all their physiological modifying factors

Introducing service improvement to the initial training of clinical staff

BACKGROUND: It is well recognised in healthcare settings that clinical staff have a major influence over change in how services are provided. If a culture of systematic service improvement is to be established, it is essential that clinical staff have an understanding of what is required and their role in its application. METHODS: This paper describes the development of short educational interventions (a module of 6-8 contact hours or a longer module of 18-30 h) for inclusion in the initial training of future clinical staff (nursing, medicine, physiotherapy, occupational therapy, dietetics, social work, operating department practice, public health and clinical psychology) and presents the results of an evaluation of their introduction. Each module included teaching on process/systems thinking, initiating and sustaining change, personal and organisational development, and public and patient involvement. RESULTS: Over 90% of students considered the modules relevant to their career. Nearly 90% of students felt that they could put their learning into practice, although the actual rate of implementation of changes during the pilot period was much lower. The barriers to implementation most commonly cited were blocks presented by existing staff, lack of time and lack of status of students within the workforce. CONCLUSION: This pilot demonstrates that short educational interventions focused on service improvement are valued by students and that those completing them feel ready to contribute. Nevertheless, the rate of translation into practice is low. While this may reflect the status of students in the health service, further research is needed to understand how this might be enhanced

Lung cancer symptom appraisal, help-seeking and diagnosis - rapid systematic review of differences between patients with and without a smoking history

BACKGROUND: Lung cancer is the leading cause of cancer death in the world. A significant minority of lung cancer patients have never smoked (14% in the UK, and ranging from 10% to 25% worldwide). Current evidence suggests that never-smokers encounter delays during the diagnostic pathway, yet it is unclear how their experiences and reasons for delayed diagnoses differ from those of current and former smokers. This rapid review assessed literature about patient experiences in relation to symptom awareness and appraisal, help-seeking, and the lung cancer diagnostic pathway, comparing patients with and without a smoking history. METHODS: MEDLINE, PsychINFO and Google Scholar were searched for studies (2010-2020) that investigated experiences of the pathway to diagnosis for patients with and without a smoking history. Findings are presented using a narrative synthesis. RESULTS: Analysis of seven quantitative and three qualitative studies revealed that some delays during symptom appraisal and diagnosis are unique to never-smokers. Due to the strong link between smoking and lung cancer, and low awareness of non-smoking related lung cancer risk factors and symptoms, never-smokers do not perceive themselves to be at risk. Never-smokers are also likely to evaluate their experiences in comparison with other non-smoking related cancers, where prognosis is likely better, potentially leading to lower satisfaction with healthcare. CONCLUSION: Never-smokers appear to have different experiences in relation to symptom appraisal and diagnosis. However, evidence in relation to help-seeking, and what is driving diagnostic delays for never-smoker patients specifically is lacking

The spatial distribution of coronae on Venus

Coronae on Venus are large, generally circular surface features that have distinctive tectonic, volcanic, and topographic expressions. They range in diameter from less than 200 km to at least 1000 km. Data from the Magellan spacecraft have now allowed complete global mapping of the spatial distribution of coronae on the planet. Unlike impact craters, which show a random (i.e., Poisson) spatial distribution, the distribution of coronae appears to be nonrandom. We investigate the distribution here in detail, and explore its implications in terms of mantle convection and surface modification processes

Noncanonical quantum optics

Modification of the right-hand-side of canonical commutation relations (CCR) naturally occurs if one considers a harmonic oscillator with indefinite frequency. Quantization of electromagnetic field by means of such a non-CCR algebra naturally removes the infinite energy of vacuum but still results in a theory which is very similar to quantum electrodynamics. An analysis of perturbation theory shows that the non-canonical theory has an automatically built-in cut-off but requires charge/mass renormalization already at the nonrelativistic level. A simple rule allowing to compare perturbative predictions of canonical and non-canonical theories is given. The notion of a unique vacuum state is replaced by a set of different vacua. Multi-photon states are defined in the standard way but depend on the choice of vacuum. Making a simplified choice of the vacuum state we estimate corrections to atomic lifetimes, probabilities of multiphoton spontaneous and stimulated emission, and the Planck law. The results are practically identical to the standard ones. Two different candidates for a free-field Hamiltonian are compared.Comment: Completely rewritten version of quant-ph/0002003v2. There are overlaps between the papers, but sections on perturbative calculations show the same problem from different sides, therefore quant-ph/0002003v2 is not replace