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Two-stage Classification for Detecting Murmurs from Phonocardiograms Using Deep and Expert Features
No full textDetection of heart murmurs from stethoscope sounds is a key clinical technique used to identify cardiac abnormalities. We describe the creation of an ensemble classifier using both deep and hand-crafted features to screen for heart murmurs and clinical abnormality from phonocardiogram recordings over multiple auscultation locations. The model was created by the team Murmur Mia! for the George B. Moody PhysioNet Challenge 2022.Methods: Recordings were first filtered through a gradient boosting algorithm to detect Unknown. We assume that these are related to poor quality recordings, and hence we use input features commonly used to assess audio quality. Two further models, a gradient boosting model and ensemble of convolutional neural networks, were trained using time-frequency features and the mel-frequency cepstral coefficients (MFCC) as inputs, respectively. The models were combined using logistic regression, with bespoke rules toconvert individual recording outputs to patient predictions.Results: On the hidden challenge test set, our classifier scored 0.755 for the weighted accuracy and 14228 for clinical outcome challenge metric. This placed 9/40 and 28/39 on the challenge leaderboard, for each scoring metric, respectively.<br/
Childcare Support under Social Security in the UK: Is it Working?
No full textBy facilitating engagement in the labour force and thus potentially contributing to the amelioration of individual poverty, the availability of affordable childcare is an issue of both economic and social significance and is recognised as such across Europe. Since a large majority of the parents who assume caring responsibilities for young children, particularly lone parents, are women, childcare support is also seen as an equality issue in relation to employment. Children’s interest in the parents’ childcare support is also recognised under the UN Convention on the Rights of the Child. Support towards the cost of childcare has been an important feature of the UK social security system since the 1980s and is currently located within Universal Credit (UC) and Working Tax Credit (WTC) legislation. UC and WTC support sits alongside other childcare support schemes, including Tax-free Childcare. For the most disadvantaged, it is however the social security system’s role in this field that has the greatest importance, not least because the imposition of work conditionality and particularly its extension to lone parents with young children is premised on the claimant’s ability to access childcare arrangements. This article evaluates the framework for supporting childcare costs within the social security system in the light of the evidence to date on its operation, including the inherent discrimination that prompted the recent judicial review challenge in Salvato. It highlights flaws in the system and among other things calls for increased monitoring and public scrutiny of its operation
Mineral diagenesis in a carbonate-rich mudstone: The Lower Carboniferous Hodder Shale, UK
No full textMineral authigenesis in mudstones respond differently across the compositional spectrum of fine-grained rocks resulting in a complex array of possible rock fabrics that affect the mechanical capacity of mudstones. Within carbonate-rich mudstones, geochemical controls on silicate and carbonate mineral reactions are variable and poorly understood. Here we analyse the diagenetic minerals of the carbonate-rich Hodder Mudstone from the Carboniferous Bowland Basin, UK, using SEM petrography combined with X-ray-based inorganic geochemical data. Our findings show that up to 90% of quartz cement in the samples are diagenetic in origin, originating mainly from biogenic silica dissolution, and clay mineral reactions. It is also evident that due to the varying diagenetic silica-yielding reactions, authigenic silica overgrowths and isolated authigenic quartz crystals are localised in argillaceous samples while calcareous samples are characterized by silica replacement textures and quartz/calcite intergrowths. Moreover, euhedral dolomite crystals are concentrated within argillaceous units in comparison with calcareous units which are characterised by anhedral dolomite precipitation and replacement textures. These finding presents a case for facies28 selective cementation as both early and burial diagenetic alterations were observed to be controlled by primary depositional components of biogenic debris and extrabasinal silicate detritus that resulted in complex and variable precipitation of authigenic minerals
IDENTIFYING THE BEST METHODS TO REPORT ON THE POST-VACCINATION SURVEILLANCE OF PHYSICAL SIDE-EFFECTS OF THE COVID-19 VACCINES: A SYSTEMATIC REVIEW
No full textIntroduction: On the 11th of March 2020, the World Health Organisation declared COVID-19 to be a global pandemic. This had led to the development of many novel vaccines for which effective post-vaccination surveillance is essential. This study aims to synthesise post-vaccination surveillance of physical side-effects to learn the best method that can be applied to the surveillance of novel COVID-19 vaccines. Methods: A full systematic search was performed on four databases following the PRISMA guidelines. Following the inclusion and exclusion criteria, and hand-searching the eligible papers, a total of seven studies were included in this review. The risk of bias within studies and their quality was assessed using the Critical Appraisal for Public Health Checklist.Results: The seven studies included were from six countries representing both active and passive surveillance systems. The results showed reliability and reproducibility between data across countries. They also provided a good framework for how post-vaccination surveillance can be performed in low-income countries. Conclusions: The reporting of post-vaccine side-effects is essential. Active and passive systems were essential to encourage reporting of AEFIs and should be encouraged globally. A combination of active and passive surveillance should be used to monitor adverse events relating to the novel COVID-19 vaccines
Determination of substrate addition order strategy for bespok Polyhydroxyalkanoates production: a Molecular Modeling based approach
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A Perspective on Welding Technology Challenges in the Nuclear Sector
No full textThis article describes three areas that, in the opinion of the author, should be priorities for development in the nuclear sector. The application of electron-beam (or laser in vacuo) welding to pressure vessel fabrication; the optimisation of filler metal compositions for multipass steel welds; and the pre-fabrication of dissimilar metal transition pieces are each highlighted and discussed. While conceived with the nuclear sector in mind, these priority areas are relevant more generally to the welding of pressure vessels, piping and similar structures. The intention is to stimulate ideas, to provoke debate, and to encourage the welding community to rise to the challenges that must be overcome as we transition to a low-carbon future
Structure restoration and coarsening of nanocrystalline cementite in cold drawn pearlitic wire induced by low temperature annealing
No full textInternal structure evolution of nano-scale cementite during annealing has exhibited a critical impact on mechanical performance for various heavily strained high-carbon steel materials. Through a combination of post-annealing and in-situ annealing transmission electron microscopy observations, structural evolution of heavily strained cementite during low-temperature annealing was investigated. During annealing, the morphology of cementite lamellae is stable when the temperature (Ta) is lower than 350 °C. Meanwhile, lattice structure restoration and coarsening of nanocrystalline cementite (θ- NC) occurred inside the lamellae. Starting from a nanocrystalline structure in the as-drawn state, the interiors of cementite lamellae were observed to transform into coarsened isometric shape θ-NC (140 °C < Ta < 210 °C) or elongated θ-NC (Ta < 350 °C). The coarsening activation energy of heavily strained cementite nanocrystalline in lamellae is estimated to be in a range of 37 ~ 50 kJ mol-1, while the coarsening behaviour is limited by the ferrite-cementite phase boundary
Peer-to-Peer, Community Self-Consumption, and Transactive Energy: A Systematic Literature Review of Local Energy Market Models
No full textPeer-to-peer, community or collective self-consumption, and transactive energy markets offer new models for trading energy locally. Over the past five years, there has been significant growth in the amount of academic literature examining how these local energy markets might function. This systematic literature review of 139 peer-reviewed journal articles examines the market designs used in these energy trading models. A modified version of the Business Ecosystem Architecture Modelling framework is used to extract market model information from the literature, and to identify differences and similarities between the models. This paper examines how peer-to-peer, community self-consumption and transactive energy markets are described in current literature. It explores the similarities and differences between these markets in terms of participation, governance structure, topology, and design. This paper systematises peer-to-peer, community self-consumption and transactive energy market designs, identifying six archetypes. Finally, it identifies five evidence gaps which require future research before these markets could be widely adopted. These evidence gaps are the lack of: consideration of physical constraints; a holistic approach to market design and operation; consideration about how these market designs will scale; consideration of information security; and, consideration of market participant privacy
A Laser-Atom Interaction Simulator derived from Quantum Electrodynamics
No full textA laser-atom interaction simulator derived from quantum electrodynamics (LASED) is presented, which has been developed in the python programming language. LASED allows a user to calculate the time evolution of a laser-excited atomic system. The model allows for any laser polarization, a Gaussian laser beam profile, a rotation of the reference frame chosen to define the states, and an averaging over the Doppler profile of an atomic beam. Examples of simulations using LASED are presented for excitation of calcium from the 41S0 state to the 41P1 state, for excitation from the helium 31D2 state excited by electron impact to the 101P1 state, and for laser excitation of caesium via the D2 line
Cascade adsorptive separation of light hydrocarbons by commercial zeolites
No full textAdsorptive separation of light hydrocarbons by porous solids provides an energy-efficient alternative to state-of-the-art cryogenic distillation. However, an optimal balance between the cost, performance and stability of the sorbent material is yet to be achieved for industrial applications. Here, we report the efficient separation of C2 and C3 hydrocarbons by a faujasite zeolite (Na-X, Si/Al=1.23). A tandem configuration of two fixed-beds packed with Na-X affords complete dynamic separation of the ternary mixture of C2H2/C2H4/C2H6 (1/49.5/49.5; v/v/v) under ambient conditions. Pressure-swing desorption on the latter fixed-bed gives ethylene (>99.50%, 1.80 mmol g-1) and ethane (>99.99%, 1.41 mmol g-1). In situ synchrotron X-ray powder diffraction revealed the binding sites for C2H2 and C2H4 in Na-X. This study highlights the potential application of commercial zeolites for challenging industrial separations