Improved hydrogen gas production in microbial electrolysis cells using inexpensive recycled carbon fibre fabrics

Growing energy demands of wastewater treatment have made it vital for water companies to develop less energy intensive processes for treating wastewater if net zero emissions are to be achieved by 2050. Microbial electrolysis cells (MECs) have the potential to do this by treating water and producing renewable hydrogen gas as a product, but capital and operational costs have slowed their deployment. By using recycled carbon fibre mats, commercially viable MECs can brought closer to reality, where recycled carbon fibre anode MECs treating real wastewater (normalised ~3100 L d−1) were producing 66.77 L H2 d−1 while graphite felt anode MECs produced 3.65 L H2 d−1 per 1 m3 reactor, anodes costing £5.53 m−2 and £88.36 m−2 respectively, resulting in a total anode cost saving of 93%. This could incentivise the development of larger pilot systems, opening the door for generating greater value and a more sustainable wastewater treatment industry

Thermally stable low current consuming gallium and germanium chalcogenides for consumer and automotive memory applications

The phase change technology behind rewritable optical disks and the latest generation of electronic memories has provided clear commercial and technological advances for the field of data storage, by virtue of the many well known attributes, in particular scaling, cycling endurance and speed, that chalcogenide materials offer. While the switching power and current consumption of established germanium antimony telluride based memory cells are a major factor in chip design in real world applications, often the thermal stability of the device can be a major obstacle in the path to the full commercialisation. In this work we describe our research in material discovery and characterization for the purpose of identifying more thermally stable chalcogenides for applications in PCRAM

Quantising the electromagnetic field in position space

In a recent paper [Southall et al., Locally-acting mirror Hamiltonians, arXiv:1908.07597 (2021)], we showed that it is possible to design locally-acting mirror Hamiltonians which only affect incoming but do not change the dynamics of outgoing wave packets. To better justify our approach, this paper presents a systematic quantisation of the electromagnetic field in position space. Starting from the assumption that the basic building blocks of the electromagnetic field in one dimension are localised bosonic wave packets with a clear direction of propagation -- so-called bosons localised in position (BLiPs) -- we identify the relevant Schroedinger equation and construct Lorentz covariant electric and magnetic field observables. Our description contains the standard description of the quantised electromagnetic field which is shown to apply to a subspace of states.Comment: 15 pages, no figure

Manifestation of classical wave delays in a fully quantized model of the scattering of a single photon

We consider a fully quantized model of spontaneous emission, scattering, and absorption, and study propagation of a single photon from an emitting atom to a detector atom both with and without an intervening scatterer. We find an exact quantum analog to the classical complex analytic signal of an electromagnetic wave scattered by a medium of charged oscillators. This quantum signal exhibits classical phase delays. We define a time of detection which, in the appropriate limits, exactly matches the predictions of a classically defined delay for light propagating through a medium of charged oscillators. The fully quantized model provides a simple, unambiguous, and causal interpretation of delays that seemingly imply speeds greater than c in the region of anomalous dispersion.Comment: 18 pages, 4 figures, revised for clarity, typos corrrecte

Which features of primary care affect unscheduled secondary care use?:A systematic review

OBJECTIVES: To conduct a systematic review to identify studies that describe factors and interventions at primary care practice level that impact on levels of utilisation of unscheduled secondary care. SETTING: Observational studies at primary care practice level. PARTICIPANTS: Studies included people of any age of either sex living in Organisation for Economic Co-operation and Development (OECD) countries with any health condition. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome measure was unscheduled secondary care as measured by emergency department attendance and emergency hospital admissions. RESULTS: 48 papers were identified describing potential influencing features on emergency department visits (n=24 studies) and emergency admissions (n=22 studies). Patient factors associated with both outcomes were increased age, reduced socioeconomic status, lower educational attainment, chronic disease and multimorbidity. Features of primary care affecting unscheduled secondary care were more complex. Being able to see the same healthcare professional reduced unscheduled secondary care. Generally, better access was associated with reduced unscheduled care in the USA. Proximity to healthcare provision influenced patterns of use. Evidence relating to quality of care was limited and mixed. CONCLUSIONS: The majority of research was from different healthcare systems and limited in the extent to which it can inform policy. However, there is evidence that continuity of care is associated with reduced emergency department attendance and emergency hospital admissions

Ponderomotive light squeezing with atomic cavity optomechanics

Accessing distinctly quantum aspects of the interaction between light and the position of a mechanical object has been an outstanding challenge to cavity-optomechanical systems. Only cold-atom implementations of cavity optomechanics have indicated effects of the quantum fluctuations in the optical radiation pressure force. Here we use such a system, in which quantum photon-number fluctuations significantly drive the center of mass of an atomic ensemble inside a Fabry-Perot cavity. We show that the optomechanical response both amplifies and ponderomotively squeezes the quantum light field. We also demonstrate that classical optical fluctuations can be attenuated by 26 dB or amplified by 20 dB with a weak input pump power of < 40 pW, and characterize the optomechanical amplifier's frequency-dependent gain and phase response in both the amplitude and phase-modulation quadratures

Quality of questionnaires for the assessment of otitis media with effusion in children

Objectives Audiometric tests provide information about hearing in otitis media with effusion (OME). Questionnaires can supplement this information by supporting clinical history‐taking as well as potentially providing a standardized and comprehensive assessment of the impact of the disease on a child. There are many possible candidate questionnaires. This study aimed to assess the quality and usability of parent / child questionnaires in OME assessment. Design and main outcome measures Fifteen, published questionnaires, commonly used in audiological departments (Auditory Behaviour in Everyday Life (ABEL), Children's Auditory Performance Scale (CHAPS), Children's Home Inventory for Listening Difficulties (CHILD), Children's Outcome Worksheets (COW), Evaluation of Children's Listening and Processing Skills (ECLiPS), Early Listening Function (ELF), Fisher's Auditory Problem Checklist (FAPC), Hearing Loss 7 (HL‐7), Listening Inventory for Education‐ Revised (LIFE‐R Student), Listening Inventory for Education UK Individual Hearing Profile (LIFE‐UK IHP), LittlEARS Auditory Questionnaire (LittlEARS), Listening Situations Questionnaire (LSQ), Otitis Media 6 (OM‐6), Quality of Life in Children's Ear Problems (OMQ‐14), Parents’ Evaluation of Aural/Oral Performance of Children (PEACH) were assessed according to the following 8 criteria: conceptual clarity, respondent burden, reliability, validity, normative data, item bias, ceiling/ floor effects, and administrative burden. Results ECLiPS, LittlEARS and PEACH scored highest overall based on the assessment criteria established for this study. None of the questionnaires fully satisfied all 8 criteria. Although all questionnaires assessed issues considered to be of at least adequate relevance to OME, the majority had weaknesses with respect to the assessment of psychometric properties, such as item bias, floor/ceiling effects or measurement reliability and validity. Publications reporting on the evaluation of reliability, validity, normative data, item bias and ceiling/floor effects were not available for most of the questionnaires. Conclusions This formal evaluation of questionnaires, currently available to clinicians, highlights three questionnaires as potentially offering a useful adjunct in the assessment of OME in clinical or research settings. These were the ECLiPS, which is suitable for children aged 6 years and older, and either the LittlEARS or the PEACH for younger children. The latter two are narrowly focused on hearing, whereas ECLiPS has a broader focus on listening, language and social difficulties

Why do patients seek primary medical care in emergency departments? An ethnographic exploration of access to general practice

Objectives: To describe how processes of primary care access influence decisions to seek help at the emergency department (ED).Design: Ethnographic case study combining non-participant observation, informal and formal interviewing.Setting: Six general practitioner (GP) practices located in three commissioning organisations in England.Participants and methods: Reception areas at each practice were observed over the course of a working week (73 hours in total). Practice documents were collected and clinical and non-clinical staff were interviewed (n=19). Patients with recent ED use, or a carer if aged 16 and under, were interviewed (n=29).Results: Past experience of accessing GP care recursively informed patient decisions about where to seek urgent care, and difficulties with access were implicit in patient accounts of ED use. GP practices had complicated, changeable systems for appointments. This made navigating appointment booking difficult for patients and reception staff, and engendered a mistrust of the system. Increasingly, the telephone was the instrument of demand management, but there were unintended consequences for access. Some patient groups, such as those with English as an additional language, were particularly disadvantaged, and the varying patient and staff semantic of words like ‘urgent’ and ‘emergency’ was exacerbated during telephone interactions. Poor integration between in-hours and out-of-hours care and patient perceptions of the quality of care accessible at their GP practice also informed ED use.Conclusions: This study provides important insight into the implicit role of primary care access on the use of ED. Discourses around ‘inappropriate’ patient demand neglect to recognise that decisions about where to seek urgent care are based on experiential knowledge. Simply speeding up access to primary care or increasing its volume is unlikely to alleviate rising ED use. Systems for accessing care need to be transparent, perceptibly fair and appropriate to the needs of diverse patient groups